| Question: | Using RIP, how do we configure R1 so that only R2 knows about the 192.168.5.x/24 network.
A. router rip network 192.168.1.0 network 192.168.5.0 neighbor 192.168.1.3
B. router rip passive-interface ethernet 0 network 192.168.1.0 network 192.168.5.0
C. router rip passive-interface ethernet 1 network 192.168.1.0 network 192.168.5.0 neighbor 192.168.1.3
D. router rip passive-interface ethernet 0 network 192.168.1.0 network 192.168.5.0 neighbor 192.168.1.3
E. router rip passive-interface ethernet 1 network 192.168.1.0 network 192.168.5.0
|
| Answer: | D. router rip passive-interface ethernet 0 network 192.168.1.0 network 192.168.5.0 neighbor 192.168.1.3
|
| Explanation: | By using the passive-interface router configuration command we block the sending of broadcast updates on the network. Because R2 needs to know about the 192.168.5.0/24 network we use the neighbor command to send out unicast updates to R2. R2 needs also to be configured in a similar way otherwise R3 would learn about 192.168.5.0/24 network via R2. |
|
| Question: | We want to advertise only a default route via EIGRP. How do we achieve this?
A. R1(config)#router EIGRP 1000 R1(config-router)#neighbor 172.16.1.25 default-originate always
B. R1(config)#router EIGRP 1000 R1(config-router)#ip summary-address eigrp 1000 0.0.0.0 0.0.0.0
C. R1(config)#interface serial0 R1(config-if)#ip summary-address eigrp 1000 0.0.0.0 0.0.0.0
D. R1(config)#ip summary-address eigrp 1000 0.0.0.0 0.0.0.0
|
| Answer: | C. R1(config)#interface serial0 R1(config-if)#ip summary-address eigrp 1000 0.0.0.0 0.0.0.0
|
| Explanation: | To advertise just a default route and suppress all other routing updates we use the ip summary-address eigrp as_number 0.0.0.0 0.0.0.0 command in interface configuration mode. Replacing 0.0.0.0 0.0.0.0 with a summary address and network mask will advertise that summary route. We also need to disable the automatic summarization with the no auto-summary router configuration command. |
|
| Question: | EIGRP uses the following tables?
A. Neighbor table
B. Cost table
C. Topology table
D. Link-state table
E. Route/Forwarding table
F. EIGRP table
|
| Answer: | A. Neighbor table
C. Topology table
E. Route/Forwarding table
|
| Explanation: | The neighbor table contains every formed adjacency. The topology table is where all the learned routes are kept. The route/forwarding table contains the lowest composite metric routes. |
|
| Question: | When using autoconfiguration with IPv6 what are the minimum requirements?
A. R1(config)#ipv6 unicast-routing R1(config)#interface type R1(config-if)#ipv6 enable
B. R1(config-if)#ipv6 unicast-routing
C. R1(config)#ipv6 unicast-routing R1(config-router)#ipv6 enable
D. R1(config)#ipv6 unicast-routing
|
| Answer: | A. R1(config)#ipv6 unicast-routing R1(config)#interface type R1(config-if)#ipv6 enable
|
| Explanation: | When a node initializes it generates a link-local address for that interface. The link-local address is the interface?s identifier concatenated with the well-known link-local prefix FE80:: The rightmost zeros of the link-local prefix are replaced with the interface ID.
Example, link-local prefix FE80:0:0:0:0:0:0:0 and interface ID 200:CFF:FE0A.2C51 form link-local address FE80:0:0:0:200:CFF:FE0A.2C51 The node then initiates the duplicate address detection progress and if no duplicate address exists then the node assigns the generated local-link address to the interface. |
|
| Question: | We want to redistribute our RIP routes into OSPF. What is the correct configuration to achieve this?
A. R1(config)#router ospf R1(config-router)#redistribute rip subnets
B. R1(config)#router rip R1(config-router)#redistribute ospf
C. R1(config)#router ospf 100 R1(config-router)#redistribute rip subnets
D. R1(config)#redistribute rip ospf
|
| Answer: | C. R1(config)#router ospf 100 R1(config-router)#redistribute rip subnets
|
| Explanation: | The redistribute command allows to inject routes from one routing protocol into another. The subnets keyword is needed to redistribute subnetted routes otherwise only non-subnetted routes are redistributed. |
|
| Question: | What happens when a Designated Router fails in an OSPF network?
A. An election is held between all the Backup Designated Routers and the Backup Designated Router with the lowest priority becomes the Designated Router
B. The Backup Designated Router takes over the role of Designated Router even if the Designated Router comes back online and a new Backup Designated Router is elected
C. The Backup Designated Router takes over the role of Designated Router but seizes to have this role when the original Designated Router comes back online and a new Backup Designated Router is elected
D. An election is held between all the Backup Designated Routers and the Backup Designated Router with the highest priority becomes the Designated Router
|
| Answer: | B. The Backup Designated Router takes over the role of Designated Router even if the Designated Router comes back online and a new Backup Designated Router is elected
|
| Explanation: | A significant problem with the Designated Router (DR) scheme is that if the DR fails, a new DR must be elected. New adjacencies must be established, and all routers on the network must synchronize their databases with the new DR (part of the adjacency-building process). While all this is happening, the network is unavailable for transit packets.
To prevent this problem, a Backup Designated Router (BDR) is elected in addition to the DR. All routers form adjacencies not only with the DR but also with the BDR. The DR and BDR also become adjacent with each other. If the DR fails, the BDR becomes the new DR. Because the other routers on the network are already adjacent with the BDR, network unavailability is minimized.
When an OSPF router becomes active and discovers its neighbours, it checks for an active DR and BDR. If a DR and BDR exist, the router accepts them. If there is no BDR, an election is held in which the router with the highest priority becomes the BDR. If more than one router has the same priority, the one with the numerically highest Router ID wins. If there is no active DR, the BDR is promoted to DR and a new election is held for the BDR.
It should be noted that the priority can influence an election, but will not override an active DR or BDR. That is, if a router with a higher priority becomes active after a DR and BDR have been elected, the new router will not replace either of them. So the first two DR-eligible routers to initialize on a multi-access network will become the DR and BDR. |
|
| Question: | What type of LSAs are not flooded into a totally stubby area?
A. LSA type 2
B. LSA type 1
C. LSA type 5
D. LSA type 4
|
| Answer: | C. LSA type 5
D. LSA type 4
|
| Explanation: | Because totally stubby areas use a default route to all destinations (external to the AS and area) the ABR will block LSA type 4 and 5 but also all summary LSAs with the exception of a single type 3 LSA to advertise the default route. |
|
| Question: | What type of LSA are used to advertise routes that have been redistributed into OSPF?
A. LSA type 1
B. LSA type 3
C. LSA type 7
D. LSA type 5
|
| Answer: | D. LSA type 5
|
| Explanation: | LSA type 5 or Autonomous System External LSAs are used to advertise routes that have been redistributed into OSPF. They are flooded throughout the entire system except for stub, totally stub and not-so-stubby areas. |
|
| Question: | How can we influence the DR and BDR election?
A. R1(config)#interface ethernet0 R1(config-if)#ip priority 220
B. R1(config)#interface ethernet0 R1(config-if)#ip ospf priority 0
C. R1(config)#interface ethernet0 R1(config-if)#ip ospf priority 220
D. R1(config)#router ospf 10 R1(config-router)#priority 220
|
| Answer: | C. R1(config)#interface ethernet0 R1(config-if)#ip ospf priority 220
|
| Explanation: | The ip ospf priority command will set a value to the interface that will be used when the DR and BDR is elected. The highest priority will win the election, in case of a tie the highest RID will win. |
|
| Question: | What command do we use to view the state of adjacencies formed with other routers in OSPF?
A. Show ip ospf neighbor
B. Show ip ospf database summary
C. Show ip ospf detail
D. Show ip ospf database
|
| Answer: | A. Show ip ospf neighbor
|
| Explanation: | The show ip ospf neighbor command shows the operational status of all OSPF neighbors (adjacencies). |
|
| Question: | A route external to the OSPF AS that does not take the cost to the ASBR into account is entered in the routing table with the following code?
A. O E1
B. O
C. O E2
D. O IA
|
| Answer: | C. O E2
|
| Explanation: | Type 2 external paths (E2) are routes external to the OPSF AS and do no take the cost into account of the path to the ASBR. |
|
| Question: | We want to inject a summary route, from other OSPF areas, into the backbone area 0 from an ABR. What command do we use?
A. area x range network networkmask
B. summary-address network networkmask
C. area network networkmask
D. summary-route network networkmask
|
| Answer: | A. area x range network networkmask
|
| Explanation: | To inject a summary route of other OSPF areas via the ABR into the backbone we use the area area_id range network_address network_mask router configuration command on the ABR. |
|
| Question: | A network LSA originates from which router?
A. DR
B. ABR
C. ASBR
D. BDR
|
| Answer: | A. DR
|
| Explanation: | Network LSAs (type 2) originate from the DR on every multi-access network and list all attached routers including it self. |
|
| Question: | Which of the following are well-known mandatory attributes?
A. Aggregator
B. Next_hop
C. Atomic_Aggregate
D. AS_path
E. Multi_Exit_Disc
F. Local_Pref
|
| Answer: | B. Next_hop
D. AS_path
|
| Explanation: | The 3 well-known mandatory attributes are:
- Origin
- AS_Path
- Next_Hop
|
|
| Question: | We want to configure EIGRP on R1 but E1 is not allowed to participate in the EIGRP process. How do we achieve this?
A. R1(config)#router eigrp 10 R1(config-router)#network 10.1.1.1 R1(config-router)#network 192.168.1.0
B. R1(config)#router eigrp 10 R1(config-router)#network 10.1.1.1 R1(config-router)#network 192.168.1.0 R1(config)#interface ethernet 1 R1(config-if)#ip eigrp passive
C. R1(config)#router eigrp 10 R1(config-router)#network 10.1.1.1 0.0.0.0 R1(config-router)#network 192.168.1.0
D. R1(config)#router eigrp 10 R1(config-router)#network 10.1.1.1 0.0.0.0 as 10 R1(config-router)#network 192.168.1.0
|
| Answer: | C. R1(config)#router eigrp 10 R1(config-router)#network 10.1.1.1 0.0.0.0 R1(config-router)#network 192.168.1.0
|
| Explanation: | Since the release of IOS 12.01(T) the network statement was given the ability to use wildcard masks like OSPF. Prior to that IOS release the router (IOS) would correct the address to the major classful network number, in this case 10.0.0.0 which would include ethernet 1. In earlier releases this would be achieved with the passive-interface router configuration command. |
|
| Question: | Which of the following statements are true about route reflectors?
A. If a route is received from a client, advertise the route to the other clients and non clients
B. if a route is received from a non client advertise the route to all the clients
C. If a route is received from an eBGP peer advertise the route to all clients but not to the non clients
D. If a route is received from a non client, drop the route
|
| Answer: | A. If a route is received from a client, advertise the route to the other clients and non clients
B. if a route is received from a non client advertise the route to all the clients
|
| Explanation: | Route reflectors use the following rules:
- if the route is received from a non client peer then advertise that route to all the clients
- if the route is received from a client peer then advertise the route to all non clients and client peers
- if the route is received from an external BGP peer advertise the route to all the client and non client peers
|
|
| Question: | Which of the following statements are true about BGP?
A. BGP is a link-state protocol
B. BGP is described in RFC 1771
C. BGP does not support VLSM
D. BGP uses TCP port 179
E. Is a distance vector protocol.
|
| Answer: | B. BGP is described in RFC 1771
D. BGP uses TCP port 179
|
| Explanation: | BGP is described in RFC 1771 (http://www.ietf.org/rfc/1771rfc.txt) and uses TCP port 179 as its transport protocol. |
|
| Question: | Which of the following fields belong to the OPEN message in BGP?
A. Version
B. Autonomous system number
C. Network Layer Reachability Information
D. Hello time
E. Path attributes
|
| Answer: | A. Version
B. Autonomous system number
|
| Explanation: | The BGP OPEN message contains the following fields:
- BGP version number
- Autonomous system number
- Hold time
- BGP identifier
- Optional parameters
|
|
| Question: | In which order are the following six decisions evaluated during the BGP decision process?
A. First,Second,Third,Fouth,Fifth,Sixth
B. Next Hop Availability,Highest Administrative Weight,Highest Local Prefernece,Shortest AS Path,Lowest MED,External over Internal BGP
|
| Answer: | B. Next Hop Availability,Highest Administrative Weight,Highest Local Prefernece,Shortest AS Path,Lowest MED,External over Internal BGP
|
| Explanation: | The BGP decision process follows the following steps:
- if the next hop is unavailable ignore the route
- prefer the path with the highest administrative weight (Cisco proprietary)
- if the weights are equal prefer the route with the highest local preference
- if the local preferences are equal prefer the route with the shortest AS_Path
- if the AS_Paths are equal prefer the route with the lowest origin type
- if the origin type is the same prefer the route with the lowest MED
- if the MED is equal prefer external BGP routes over internal BGP routes
- if everything is still equal prefer the route with the shortest path to the BGP Next_Hop, i.e. the route with the lowest IGP metric to the next-hop router
- the last step is prefer the route advertised by the router with the lowest RID |
|
| Question: | When configuring BGP we want to use loopback0 as the interface to establish the peering sessions. How can we achieve this?
A. neighbor 10.1.1.1 remote-as 1 neighbor 10.1.1.1 update-peer loopback0
B. neighbor 10.1.1.1 remote-as 1 neighbor 10.1.1.1 update-interface loopback0
C. neighbor 10.1.1.1 remote-as 1 neighbor 10.1.1.1 update-source loopback0
D. neighbor 10.1.1.1 remote-as 1 neighbor 10.1.1.1 peer loopback0
|
| Answer: | C. neighbor 10.1.1.1 remote-as 1 neighbor 10.1.1.1 update-source loopback0
|
| Explanation: | The update-source command used in combination with the neighbor command lets us choose the interface we will use as a source IP address for the peering session with that neighbor. |
|
| Question: | What is the origin code for a route originated on a BGP router?
A. 2
B. 3
C. 1
D. 0
|
| Answer: | D. 0
|
| Explanation: | Origin Code Origin Code name Description
0 IGP Route originated from a BGP router.
1 EGP Route originated from an EGP (not eBGP)
2 Incomplete Route originated from a routing process
other then BGP via redistribution . |
|
| Question: | When electing a DIS and the priorities are all equal what will be used to elect the DIS?
A. The highest numeric SNPA
B. The highest numeric IP Address
C. The lowest numeric IP Address
D. The highest value in the TLV
E. The lowest value in the TLV
F. The lowest numeric SNPA
|
| Answer: | A. The highest numeric SNPA
|
| Explanation: | A DIS election is based on priority (default is 64) if all priorities are the default value then the highest SNPA (Subnetwork Point of Attachment), the data-link address will determine the DIS. |
|
| Question: | Which fields in an LSP packet determine if the LSP is newer then the one in the database?
A. Checksum
B. Remaining lifetime
C. Sequence number
D. LAN ID
E. Version
F. Priority
G. Holding time
|
| Answer: | A. Checksum
B. Remaining lifetime
C. Sequence number
|
| Explanation: | The tree fields used in an LSP to determine if the LSP is newer then the one in the database are:
- Remaining lifetime
- Sequence number
- Checksum |
|
| Question: | How do we change the entire router to be Level 1 only IS-IS router?
A. router isis isis circuit-type level-1
B. interface ethernet0 isis circuit-type level-1
C. interface ethernet0 is-type level-1
D. router isis is-type level-1
|
| Answer: | D. router isis is-type level-1
|
| Explanation: | We use the is-type router configuration command to change the routing level the IS-IS routing process for the entire router or for the instance of IS-IS if there are more then 1 instances running. |
|
| Question: | When a new router is with a higher priority appears on a IS-IS network what will happen to the DIS?
A. The new router will become a backup DIS and will take over the role of the current DIS when it fails.
B. The new router will become to new DIS and the old DIS becomes a backup DIS.
C. Nothing will happen and the DIS remains the same.
D. The new router will become to new DIS after a new election.
|
| Answer: | D. The new router will become to new DIS after a new election.
|
| Explanation: | When a DIS has a problem or a new router with a higher priority comes online a new DIS is elected in the place of the old DIS. |
|
| Question: | Which of the 4 metrics defined by ISO 10589 for Integrated IS-IS is supported by Cisco and what is its value?
A. 100
B. 64
C. Delay
D. Error
E. Expense
F. 15
G. 10
H. Default
|
| Answer: | G. 10
H. Default
|
| Explanation: | The default or cost is the only out of the 4 metrics of IS-IS supported by Cisco. Its default value is 10 on all interfaces. |
|
| Question: | IGRP sends out periodic updates every _________ seconds?
A. 120
B. 630
C. 90
D. 30
E. 180
|
| Answer: | C. 90
|
| Explanation: | By default IGRP sends out periodic updates every 90 seconds. |
|
| Question: | How do we achieve load balancing across unequal paths in EIGRP?
A. variance
B. traffic-share min
C. traffic-share max
D. maximum-paths
|
| Answer: | A. variance
|
| Explanation: | The variance command can be used to load balance across unequal cost paths. Traffic-share min needs the across-interfaces keyword to have the same result otherwise it uses equal cost paths. |
|
| Question: | Hop count in IGRP is used for?
A. limit the diameter of the network
B. primary metric
C. secondary metric after the composite metric of bandwidth and delay
D. IGRP does not have a hop count
|
| Answer: | A. limit the diameter of the network
|
| Explanation: | By default the hop count in IGRP is 100 but it can be configured to 255 and is used to limit the diameter of the network. |
|
| Question: | The administrative distance of an EIGRP summary route is?
A. 120
B. 5
C. 90
D. 170
|
| Answer: | B. 5
|
| Explanation: | | Source | Administrative Distance | | Connected Interface | 0 | | Static Route | 1 | | EIGRP Summary Route | 5 | | External BGP | 20 | | Internal EIGRP | 90 | | IGRP | 100 | | OSPF | 110 | | IS-IS | 115 | | RIP | 120 | | EGP | 140 | | On Demand Routing (ODR) | 160 | | External EIGRP | 170 | | Internal BGP | 200 | |
|
| Question: | Which of the following routing protocols are interior routing protocols?
A. OSPF
B. EGP
C. IS-IS
D. BGP
E. EIGRP
F. RIPv2
|
| Answer: | A. OSPF
C. IS-IS
E. EIGRP
F. RIPv2
|
| Explanation: | RIPv1 & v2, OSPF, IGRP, EIGRP and IS-IS are considered interior routing protcols because they run inside the enterprise. Exterior routing protocols like BGP and EGP are/were used to exchange routing information between enterprises. |
|
| Question: | Link-state routing protocols reduce the network overhead by using?
A. By using broadcast updates.
B. By sending triggered updates that contain only the change instead of the entire routing table.
C. By sending of the entire routing table in each update.
D. By using multicast updates.
E. By not using hop count as a metric.
|
| Answer: | B. By sending triggered updates that contain only the change instead of the entire routing table.
D. By using multicast updates.
|
| Explanation: | Link-state routing protocols some of the following techniques to reduce the network overhead:
- use of multicast addressing
- sending of triggered updates
- infrequently sending network summaries
- not sending the entire routing table with every updated |
|
| Question: | BGP uses which metric?
A. cost
B. hop count
C. attributes
D. composite metric
|
| Answer: | C. attributes
|
| Explanation: | BGP has a complex metric called attributes by which traffic paths can be manipulated. |
|
| Question: | We want to reset all BGP sessions. How do we achieve this?
A. clear ip route bgp
B. clear ip route *
C. clear ip bgp reset
D. clear ip bgp *
|
| Answer: | D. clear ip bgp *
|
| Explanation: | The clear ip bgp * command will reset all BGP sessions. |
|
| Question: | A Level 2 IS-IS router can be compared to an OSPF ________ router.
A. backbone
B. area border
C. autonomous system boundary
D. internal
|
| Answer: | A. backbone
|
| Explanation: | IS-IS L1 routers can be compared to OSPF non-backbone internal routers.
IS-IS L2 routers can be compared to OSPF backbone routers.
IS-IS L1/L2 routers can be compared to OSPF area border routers. |
|
| Question: | Which of the following statements about IS-IS are true?
A. It is a classless protocol
B. It does not support VLSM.
C. Hellos are sent every 10 seconds on all media.
D. Hellos are sent every 10 seconds on a broadcast network and every 30 seconds on a non-broadcast network.
E. If there are no hellos for 40 seconds the neighbor is declared dead.
|
| Answer: | A. It is a classless protocol
C. Hellos are sent every 10 seconds on all media.
|
| Explanation: | IS-IS is a classless protocol that supports VLSM. Hellos are sent out every 10 seconds on all media (broadcast or non-broadcast) and a neighbor is declared dead after 30 seconds of silence. |
|
| Question: | Which of the following protocols support automatic summarization at the class boundary?
A. RIP
B. OPSF
C. EIGRP
D. IS-IS
E. IGRP
F. BGP
|
| Answer: | A. RIP
C. EIGRP
E. IGRP
F. BGP
|
| Explanation: | OSPF and IS-IS do not support automatic summarization at the class boundary but summarization can be configured manually. |
|
| Question: | In EIGRP hello packets are sent every ___________ seconds?
A. 5
B. 60 on access links with a speed lower then T1
C. 10
D. 120 on access links with a speed lower then T1
E. 30
F. 30 on access links with a speed lower then T1
|
| Answer: | A. 5
B. 60 on access links with a speed lower then T1
|
| Explanation: | On most networks EIGRP sends out hello packets via multicast every 5 seconds. On multipoint X.25, Frame-Relay or ATM interfaces with access speed lower or equal to T1, hello packets are send every 60 seconds using unicast.[on point-to-point subinterfaces hellos are send every 5 seconds] |
|
| Question: | Before the databases are synchronized and LSRs are being received the OSPF router goes through different states. What is the correct order?
A. First,Second,Third,Fouth,Fifth,Sixth,Seventh
B. Down,Init,Two-Way,Exstart,Exchange,Loading,Full
|
| Answer: | B. Down,Init,Two-Way,Exstart,Exchange,Loading,Full
|
| Explanation: | An OSPF router goes through the following states:
1 down state: sends out his own hello packet
2 init state: waits 4 times the hello interval to hear a reply
3 two-way state: the router sees it own ID in the list of neighbors, adjancency is formed
4 exstart state: neighbors determine the master/slave relationship
5 exchange state: both neighbors send out database description packets
6 loading state: the router wants more details using an LSR packet
7 full state: LSRs are received and databases are updated and synchronized, the neighbors are fully adjacent |
|
| Question: | After rebooting our router we want to view the state of our OSPF adjacencies. Which command do we use?
A. show ip ospf database
B. show ip protocols
C. show ip ospf neighbor
D. show ip ospf
|
| Answer: | C. show ip ospf neighbor
|
| Explanation: | R1# show ip ospf neighbor
ID Pri State Dead Time Address Interface
192.168.1.1 1 FULL/DROTHER 0:00:45 192.168.1.1 Ethernet0
172.16.4.15 1 FULL/DROTHER 0:00:45 172.16.4.15 Ethernet0
10.1.1.4 5 FULL/DR 0:00:44 192.168.1.3 Ethernet0
Show ip ospf neighbor will give a summary line for each neighbor. The show ip ospf interface command will also display the state of the interface running OSPF. |
|
| Question: | Spanning Tree is used to prevent?
A. Routing loops
B. Unidirectional links
C. Bridging loops
D. Broadcast storms
|
| Answer: | C. Bridging loops
|
| Explanation: | Spanning Tree is used to prevent bridging loops. |
|
| Question: | The destination address of a BPDU frame is?
A. 01-08-c2-00-00-00
B. 01-00-5e-ff-ff-ff
C. 01-00-5e- followed by the MAC address of each switch in the spanning tree topology
D. ff-ff-ff-ff-ff-ff
|
| Answer: | A. 01-08-c2-00-00-00
|
| Explanation: | BPDU frames are send to the well-known STP multicast address 01-80-c2-00-00-00. |
|
| Question: | On which OSPF network topologies do we find a DR and BDR?
A. Point-to-point nonbroadcast
B. Broadcast multiaccess
C. Point-to-point
D. Nonbroadcast multiaccess
E. Point-to-multipoint
|
| Answer: | B. Broadcast multiaccess
D. Nonbroadcast multiaccess
|
| Explanation: | We find Designated Routers (DR) and Backup Designated Routers on broadcast multiaccess networks and nonbroadcast multiaccess networks. |
|
| Question: | The metric of OSPF is?
A. hop count
B. composite
C. cost
D. bandwidth
|
| Answer: | C. cost
|
| Explanation: | OSPF uses the cost as its metric, the cost is calculated by the following formula 10^8/bandwidth. |
|
| Question: | How can we set the RID on an OSPF router?
A. R1(config)#interface ethernet0 R1(config-if)#ip ospf router-id x.x.x.x
B. R1(config)#interface loopback0 R1(config-if)#ip address x.x.x.x y.y.y.y
C. R1(config)#router-id x.x.x.x
D. R1(config)#router ospf 100 R1(config-router)#router-id x.x.x.x
E. R1(config)#interface loopback0 R1(config-if)#ip ospf router-id x.x.x.x
|
| Answer: | B. R1(config)#interface loopback0 R1(config-if)#ip address x.x.x.x y.y.y.y
D. R1(config)#router ospf 100 R1(config-router)#router-id x.x.x.x
|
| Explanation: | If a loopback interface is configured on the router, the highest IP Address of the configured loopback interface(s) will be used as the router ID. We can also use the router-id command in router configuration mode. |
|
| Question: | On a frame-relay circuit the OSPF timers are?
A. dead timer 30 seconds
B. hello timer 40 seconds
C. hello timer 30 seconds
D. hello timer 10 seconds
E. dead timer 120 seconds
F. dead timer 40 seconds
G. dead timer 90 seconds
|
| Answer: | C. hello timer 30 seconds
E. dead timer 120 seconds
|
| Explanation: | Serial interfaces with frame relay encapsulation are nonbroadcast network types so the hello timer is 30 seconds and the dead timer is 120 seconds. |
|
| Question: | Which of the following OSPF network statements are the same?
A. network 192.168.1.0 area 1056
B. network 192.168.1.0 0.0.0.255 area 1.0.5.6
C. network 192.168.1.0 0.0.0.255 area 0.0.10.56
D. network 192.168.1.0 0.0.0.255 area 1056
E. network 192.168.1.0 0.0.0.255 area 0.0.4.32
|
| Answer: | D. network 192.168.1.0 0.0.0.255 area 1056
E. network 192.168.1.0 0.0.0.255 area 0.0.4.32
|
| Explanation: | The area parameter can be represented in either a decimal or dotted decimal format. The dotted decimal format should be read as one binary string, e.g. decimal 1056 = 00000000.00000000.00000100.00100000 = 0.0.4.32 in dotted decimal format. |
|
| Question: | How can we influence the metric of OSPF?
A. R1(config)#router ospf 10 R1(config-router)#cost 10
B. R1(config)#router ospf 10 R1(config-router)#ip cost 10
C. R1(config)#interface serial0 R1(config-if)#bandwidth 256k
D. R1(config)#interface serial0 R1(config-if)#ip ospf cost 10
E. R1(config)#interface serial0 R1(config-if)#bandwidth 256
|
| Answer: | D. R1(config)#interface serial0 R1(config-if)#ip ospf cost 10
E. R1(config)#interface serial0 R1(config-if)#bandwidth 256
|
| Explanation: | OSPF uses cost as a metric which is derived from the formula 10^8/bandwidth. Changing the bandwidth statement of an interface running OSPF will influence the metric. We can also use the ip ospf cost value interface configuration command to influence the cost. |
|
| Question: | How can we change the default cost calculation of OSPF?
A. R1(config)#ospf auto-cost reference-bandwidth 1000
B. R1(config-router)#ospf reference-bandwidth 1000
C. R1(config-if)#ospf reference-bandwidth 1000
D. R1(config)#ospf reference-bandwidth 1000
E. R1(config)#ospf auto-cost reference-bandwidth 1000
F. R1(config-router)#ospf auto-cost reference-bandwidth 1000
|
| Answer: | F. R1(config-router)#ospf auto-cost reference-bandwidth 1000
|
| Explanation: | Using the ospf auto-cost reference-bandwidth value router configuration command we can control how OSPF calculates default metrics for the interface. The value range is 1 to 4294967, the default is 100. |
|
| Question: | How do we configure OSPF on R1 in NBMA mode?
A. R1(config)#interface serial 0 R1(config-if)# ip address 192.168.1.2 255.255.255.0 R1(config-if)#encapsulation frame-relay R1(config-if)#ip ospf network non-broadcast R1(config)#router ospf R1(config-router)#network 192.168.1.2 0.0.0.255 area 0 R1(config-router)#neighbor 192.168.1.4 R1(config-router)#neighbor 192.168.1.6
B. R1(config)#interface serial 0 R1(config-if)# ip address 192.168.1.2 255.255.255.0 R1(config-if)#encapsulation frame-relay R1(config-if)#ip ospf network non-broadcast R1(config)#router ospf 10 R1(config-router)#network 192.168.1.2 0.0.0.255 area 0
C. R1(config)#interface serial 0 R1(config-if)# ip address 192.168.1.2 255.255.255.0 R1(config-if)#encapsulation frame-relay R1(config-if)#ip ospf non-broadcast R1(config)#router ospf 10 R1(config-router)#network 192.168.1.2 0.0.0.255 area 0 R1(config-router)#neighbor 192.168.1.4 R1(config-router)#neighbor 192.168.1.6
D. R1(config)#interface serial 0 R1(config-if)# ip address 192.168.1.2 255.255.255.0 R1(config-if)#encapsulation frame-relay R1(config-if)#ip ospf network non-broadcast R1(config)#router ospf 10 R1(config-router)#network 192.168.1.2 0.0.0.255 area 0 R1(config-router)#neighbor 192.168.1.4 R1(config-router)#neighbor 192.168.1.6
|
| Answer: | D. R1(config)#interface serial 0 R1(config-if)# ip address 192.168.1.2 255.255.255.0 R1(config-if)#encapsulation frame-relay R1(config-if)#ip ospf network non-broadcast R1(config)#router ospf 10 R1(config-router)#network 192.168.1.2 0.0.0.255 area 0 R1(config-router)#neighbor 192.168.1.4 R1(config-router)#neighbor 192.168.1.6
|
| Explanation: | The ip ospf network non-broadcast command is not necessary because this is the default used in nonbroadcast multiaccess environments. There is the need however to use the neighbor statements so adjacencies can be formed. |
|
| Question: | We want to know how many times the router has recalculated its routing table. Which command do we use?
A. show ip ospf database
B. show ip ospf neighbor
C. show ip ospf
D. show ip ospf interface
|
| Answer: | C. show ip ospf
|
| Explanation: | The show ip ospf command will show how many times the SPF algorithm has been executed.
R1#show ip ospf
Routing Process "ospf 10" with ID 10.1.1.1
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
LSA group pacing timer 100 secs
Interface flood pacing timer 55 msecs
Retransmission pacing timer 100 msecs
Number of external LSA 0. Checksum Sum 0x0
Number of opaque AS LSA 0. Checksum Sum 0x0
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 2. 2 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 2
Area has message digest authentication
SPF algorithm executed 4 times
Area ranges are
Number of LSA 4. Checksum Sum 0x29BEB
Number of opaque link LSA 0. Checksum Sum 0x0
Number of DCbitless LSA 3
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
|
|
| Question: | How can make sure that a router will not become a DR or BDR?
A. ip ospf priority 0
B. ip ospf cost 0
C. no ip ospf priority
D. ip ospf priority 255
|
| Answer: | A. ip ospf priority 0
|
| Explanation: | The default priority is 1, this can be changed using the ip ospf priority command, setting the priority to 0 ensures that the router will not participate in DR or BDR elections. |
|
| Question: | Which of the following IP Addresses is a Class C Private network address?
A. 11000000.10101000.00010001.00001001
B. 11000000.10101010.00010001.00001001
C. 11000000.11101000.00010001.00001001
D. 11000000.10101001.00010001.00001001
E. 10100000.10101000.00010001.00001001
|
| Answer: | A. 11000000.10101000.00010001.00001001
|
| Explanation: | RFC1918 specifies the allocation of IP Addresses for Private Internets.
Class A 10.0.0.0 - 10.255.255.255 (10/8 prefix)
Class B 172.16.0.0 - 172.31.255.255 (172.16/12 prefix)
Class C 192.168.0.0 - 192.168.255.255 (192.168/16 prefix)
or in binary (only the first 2 otctets are represented)
Class A 0000 1010.0000 0000
Class B 1010 1100.0001 0000
Class C 1100 0000.1010 1000
|
|
| Question: | In OSPF the DRs use which IP Address to exchange link-state information?
A. 224.0.0.6
B. 224.0.0.9
C. 224.0.0.10
D. 224.0.0.5
|
| Answer: | D. 224.0.0.5
|
| Explanation: | OSPF uses 224.0.0.5 (all OSPF routers) to exchange link-state information and listens to 224.0.0.6 (all OSPF designated routers) to receive multicast updates from DRothers.
More reserverd multicast addresses can be found here: http://www.iana.org/assignments/multicast-addresses |
|
| Question: | Which command would produce the following output?
System Id SNPA Interface State Holdtime Type Protocol
0000.0000.0007 aa00.0400.6408 Ethernet0 Init 277 IS ES-IS
0000.0C00.0C35 0000.0c00.0c36 Ethernet1 Up 91 L1 IS-IS
0800.2B16.24EA aa00.0400.2d05 Ethernet0 Up 29 L1L2 IS-IS
0800.2B14.060E aa00.0400.9205 Ethernet0 Up 1698 ES ES-IS
0000.0C00.3E51 DLCI 123 Serial1 Up 28 L2 IS-IS
0000.0C00.62E6 0000.0c00.62e7 Ethernet1 Up 22 L1 IS-IS
0A00.0400.2D05 aa00.0400.2d05 Ethernet0 Init 24 IS ES-IS
A. show isis neighbors detail
B. show clns snpa
C. show isis neighbors
D. show clns neighbors detail
E. show clns neighbors
F. show isis snpa
|
| Answer: | E. show clns neighbors
|
| Explanation: | R1# show clns neighbors
System Id SNPA Interface State Holdtime Type Protocol
0000.0000.0007 aa00.0400.6408 Ethernet0 Init 277 IS ES-IS
0000.0C00.0C35 0000.0c00.0c36 Ethernet1 Up 91 L1 IS-IS
0800.2B16.24EA aa00.0400.2d05 Ethernet0 Up 29 L1L2 IS-IS
0800.2B14.060E aa00.0400.9205 Ethernet0 Up 1698 ES ES-IS
0000.0C00.3E51 DLCI 123 Serial1 Up 28 L2 IS-IS
0000.0C00.62E6 0000.0c00.62e7 Ethernet1 Up 22 L1 IS-IS 0A00.0400.2D05 aa00.0400.2d05 Ethernet0 Init 24 IS ES-IS |
|
| Question: | Looking at the following output:
R1# show isis database
IS-IS Level-1 Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL
0000.0C00.0C35.00-00 0x0000000C 0x5696 792 0/0/0
0000.0C00.40AF.00-00* 0x00000009 0x8452 1077 1/0/0
0000.0C00.62E6.00-00 0x0000000A 0x38E7 383 0/0/0
0000.0C00.62E6.03-00 0x00000006 0x82BC 384 0/0/0
0800.2B16.24EA.00-00 0x00001D9F 0x8864 1188 1/0/0
0800.2B16.24EA.01-00 0x00001E36 0x0935 1198 1/0/0
IS-IS Level-2 Link State Database
LSPID LSP Seq Num LSP Checksum LSP Holdtime ATT/P/OL
0000.0C00.0C35.03-00 0x00000005 0x04C8 792 0/0/0
0000.0C00.3E51.00-00 0x00000007 0xAF96 758 0/0/0
0000.0C00.40AF.00-00* 0x0000000A 0x3AA9 1077 0/0/0A. That that entry comes from a Pseudonode
B. That that entry comes from a Level 1 only router
C. That that entry comes from a new router still in the process of forming the adjacency
D. That that entry comes from a Level 1-2 router
|
| Answer: | D. That that entry comes from a Level 1-2 router
|
| Explanation: | ATT represents the attach bit. It indicates that the router is also a Level 2 router and it can reach other areas. Level 1 routers use the presence of this bit to identify the closest Level 1-2 router to send their out-of-area data. |
|
| Question: | In Integrated IS-IS, TLV stands for?
A. Time
B. Version
C. Lifetime
D. Packet length
E. Type
F. Length
G. Value
H. Local ciruict ID
I. Length indication
|
| Answer: | E. Type
F. Length
G. Value
|
| Explanation: | The structure of the TLV is:
- Type or Code, the type of TLV that identifies it and the characteristics that are related to it
- Length, the length of the following field
- Value, IP routes, IS-IS neighbors or authentication |
|
| Question: | We want to summarize our IP routes for Integrated IS-IS. How do we configure this?
A. interface ethernet 0 ip router isis summary-address address mask
B. router isis summary-address ip address mask
C. interface ethernet 0 ip router isis summary-address ip address mask
D. router isis summary-address address mask
|
| Answer: | D. router isis summary-address address mask
|
| Explanation: | To create IP routes summarization for Integrated IS-IS we use the summary-address address mask router configuration command. |
|
| Question: | How do we configure over NMBA in broadcast configuration?
A. interface serial1 ip address 10.1.1.1 255.255.255.0 ip router isis encapsulation frame-relay frame-relay map clns 123 frame-relay map ip 10.1.1.2 123
B. interface serial1 ip address 10.1.1.1 255.255.255.0 ip router isis encapsulation frame-relay frame-relay map isis 123 broadcast frame-relay map ip 10.1.1.2 123 broadcast
C. interface serial1 ip address 10.1.1.1 255.255.255.0 encapsulation frame-relay frame-relay map clns 123 broadcast frame-relay map ip 10.1.1.2 123
D. interface serial1 ip address 10.1.1.1 255.255.255.0 ip router isis encapsulation frame-relay frame-relay map clns 123 broadcast frame-relay map ip 10.1.1.2 123 broadcast
|
| Answer: | D. interface serial1 ip address 10.1.1.1 255.255.255.0 ip router isis encapsulation frame-relay frame-relay map clns 123 broadcast frame-relay map ip 10.1.1.2 123 broadcast
|
| Explanation: | We are using the frame-relay map interface configuration command. The keyword IP is used to map the IP destination address to the DLCI and we define the interface as broadcast. Without the CLNS keyword no router appear in the IP routing table because IS-IS does not receive IS-IS frames to populate the IP routing table. |
|
| Question: | Given the following NSAP Address: 49.0005.80.0000a7.0000.ffdd.0004.1921.6801.1005.00 What is the system ID?
A. 1921.6801.1005
B. 0004
C. 49
D. 0004.1921.6801.1005.00
E. 0004.1921.6801
F. 0005.80.0000a7.0000
|
| Answer: | A. 1921.6801.1005
|
| Explanation: | The address is a GOSIP NSAP format:
49.0005.80.0000a7.0000.ffdd.0004.1921.6801.1005.00
__.____.__.______.____.____.____.______________.__
AFI.ICD.DFI.AAI.Reserved.RDI.Area.SystemID.SEL
AFI: Authority and Format Identifier
ICD: International Code Designator
DFI: Domain specific part (DSP) Format Identifier
AAI: Administrative Authority Identifier
RDI: Routing Domain Identifier (Autonomous System Number)
SEL: Network Service Access Point (NSAP) Selector
|
|
| Question: | Wich IS-IS show command will display the metric?
A. show clns databse detail
B. show isis interface
C. show clns neighbor detail
D. show isis neighbor detail
E. show isis database
F. show clns interface
|
| Answer: | F. show clns interface
|
| Explanation: | The show clns interface command will display the Level 1 and Level 2 metric of the outbound interface.
R1# show clns interface ethernet 0
Ethernet0 is up, line protocol is up
Checksums enabled, MTU 1497, Encapsulation SAP
Routing Protocol: ISIS
Circuit Type: level-1-2
Interface number 0x0, local circuit ID 0x1
Level-1 Metric: 10, Priority: 64, Circuit ID: R2.01
Number of active level-1 adjacencies: 1
Level-2 Metric: 10, Priority: 64, Circuit ID: R2.01
Number of active level-2 adjacencies: 1
Next ISIS LAN Level-1 Hello in 5 seconds
Next ISIS LAN Level-2 Hello in 1 seconds
|
|
| Question: | What is the function of a Level 2 IS-IS router?
A. To route traffic between Level 1/2 routers.
B. To locate the destination within an area.
C. To route traffic between areas.
D. To maintain the database.
|
| Answer: | C. To route traffic between areas.
|
| Explanation: | The function of a Level 2 router is to route traffic between areas. |
|
| Question: | Which EIGRP table is build using Hellos?
A. Neighbor table
B. Topology table
C. Routing table
D. Link-state database.
|
| Answer: | A. Neighbor table
|
| Explanation: | The neighbor table is build from information on Hellos received from adjacent routers (neighbors). |
|
| Question: | This state is reached when a router has sent out network packets and is waiting for ACKs from all its neighbors.
A. Passive
B. Dead
C. Active
D. Stuck in Active
|
| Answer: | C. Active
|
| Explanation: | When a router has send out network packets because of a topology change and no Feasible Successor was found it will wait for ACKs from its neighbors. The route is set to active mode. |
|
| Question: | In the EIGRP composite metric the K1 value represents?
A. MTU
B. Bandwidth
C. Loading
D. Delay
E. Reliability
|
| Answer: | B. Bandwidth
|
| Explanation: | The EIGRP Metrics are as follows:
| Symbol | Value | | K1 | Bandwidth | | K2 | Loading | | K3 | Delay | | K4 | Reliability | | K5 | MTU | |
|
| Question: | In order for EIGRP to make adjacencies which conditions have to be met?
A. The sending router must have a different AS number then the receiving one.
B. The data-link layer protocols must match.
C. The SRTT must be lower then 10 milliseconds.
D.
E. The router must hear a Hello packet or ACK from the neighbor.
F. The metric settings need to be the same
|
| Answer: | E. The router must hear a Hello packet or ACK from the neighbor.
F. The metric settings need to be the same
|
| Explanation: | In order for adjacencies to be formed the following conditions need to be met:
- The router must hear a Hello packet or an ACK from a neighbor
- The AS number in the packet header must be the same as that of the receiving router
- The metric settings need to be same. |
|
| Question: | When a route in the EIGRP topology goes down a __________ is sent when there is no FS.
A. Update
B. ACK
C. Query
D. Hello
|
| Answer: | C. Query
|
| Explanation: | Queries are sent out when a route in the topology table goes down and there is no feasible successor. |
|
| Question: | What could cause an EIGRP topology table to be recalculated?
A. The neighbor table received a reply or a query from a neighbor
B. The topology table does not receive a Hello within the holdtime
C. The routing table has removed the routes from the topology table to be put in the routing table
D. The topology table received a reply or a query from a neighbor
E. The neighbor table does not receive a Hello within the holdtime
|
| Answer: | D. The topology table received a reply or a query from a neighbor
E. The neighbor table does not receive a Hello within the holdtime
|
| Explanation: | The following reasons could cause a topology table to be recalculated: - New network is available
- topology table receives an update containing the new network
- interface for a directly connected EIGRP network comes online
- Successor is changed in the topology table and in the routing table
- topology table receives a reply or a query from a neighbor
- the cost of the link changes
- A change from a neighbor when a network has become unavailable
- topology table receives a query, reply or update the remote network is down
- neighbor table does not receive a Hello within the holdtime
- the network is directly connected and the router senses a loss of carrier |
|
| Question: | A router will be marked dead in EIGRP after _____ attempts of sending a unicast query.
A. 15
B. 7
C. 5
D. 16
E. 30
|
| Answer: | D. 16
|
| Explanation: | When a router does not hear an acknowledgment within the alloted time it will retransmit the qeury as a unicast. If after 16 attempts there is no reponse the neighbor will be marked as dead. |
|
| Question: | When can a neighbor become a feasible successor?
A. The topology table hold all routes so all neighbors are feasible successors.
B. If the feasible distance is lower then the advertised distance.
C. If the advertised distance is lower then the feasible distance.
D. If the RTO is lower then the RTP.
|
| Answer: | C. If the advertised distance is lower then the feasible distance.
|
| Explanation: | A neighbor can become a feasible successor only when its advertised distance is less than the feasible distance. This is DUALs key to remain loopfree. |
|
| Question: | This timer is used in EIGRP to determine how long the router waits for an ACK before retransmitting.
A. RTO
B. Hello
C. RTP
D. SRTT
|
| Answer: | A. RTO
|
| Explanation: | The RTO or ReTransmission Timeout is used to determine how long the router waits for an ACK before retransmitting the packet. This timer is calculated in reference to the SRTT (smooth Round-Trip Time). |
|
| Question: | EIGRP uses by default ______ % of the bandwidth.
A. 10
B. 25
C. 75
D. 100
E. 50
|
| Answer: | E. 50
|
| Explanation: | By default EIGRP uses 50% of the bandwidth of the link for its traffic, this value can be configured. |
|
| Question: | We want to see how many EIGRP Updates have been sent and received. Which command do we use?
A. show ip eigrp neigbors detail
B. show ip eigrp traffic
C. show ip eigrp interfaces
D. show ip eigrp neigbors
|
| Answer: | B. show ip eigrp traffic
|
| Explanation: | R1# show ip eigrp traffic
IP-EIGRP Traffic Statistics for process 10
Hellos sent/received: 175/165
Updates sent/received: 9/25
Queries sent/received: 4/0
Replies sent/received: 0/4
Acks sent/received: 15/10
|
|
| Question: | Which of the following messages will not use multicast in EIGRP?
A. Hello
B. Update
C. Query
D. ACK
|
| Answer: | D. ACK
|
| Explanation: | ACK are always sent unicast, it is a Hello packet with no data but the acknowledgment field has a positive number.
Updates can be multicast if there is a change in the topology and unicast if its a reply to a single router.
Hellos and Queries are always multicast. |
|
| Question: | In OSPF interarea summarization is communicated via which LSA(s)?
A. Type 5
B. Type 4
C. Type 2
D. Type 7
E. Type 3
F. Type 1
|
| Answer: | B. Type 4
E. Type 3
|
| Explanation: | LSA type 3 include the networks or subnets within an area that might have been summarized and that are sent to the backbone and between ABRs. Type 4 is information set to the ASBR from the ABR. |
|
| Question: | How do we change the time that Hellos are being sent?
A. R1(config)#interface ethernet 0 R1(config-if)#ip hello-timer eigrp 10 25
B. R1(config)#interface ethernet 0 R1(config-if)#ip hello-interval eigrp 25
C. R1(config)#interface ethernet 0 R1(config-if)#ip hello-interval eigrp 10 25
D. R1(config)#router eigrp 10 R1(config-router)#hello-interval 25
|
| Answer: | C. R1(config)#interface ethernet 0 R1(config-if)#ip hello-interval eigrp 10 25
|
| Explanation: | The ip hello-interval eigrp AS_number seconds interface configuration command will change the how often Hellos are sent to neighbors out of that interface. |
|
| Question: | What does r stand for in the output of show ip eigrp topology?
A. A reply packet was sent to this destination
B. A query packet was sent to this destination
C. An update packet was sent to this destination
D. A query has been sent and the router is waiting for a reply
|
| Answer: | D. A query has been sent and the router is waiting for a reply
|
| Explanation: | Lower case r in the show ip eigrp topology table means that the flag has been set by the software after a query packet was sent and the router is now waiting for a reply.
Router# show ip eigrp topology
IP-EIGRP Topology Table for process 10
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - Reply status
P 192.168.1.0 255.255.255.0, 2 successors, FD is 0
via 172.16.80.28 (46251776/46226176), Ethernet0
via 172.16.81.28 (46251776/46226176), Ethernet1
via 172.16.80.31 (46277376/46251776), Serial0
|
|
| Question: | What is the difference between a NET and a NSAP address?
A. A NET address is the address of the host where the value of the NSEL is set to 0x00.
B. A NSAP address is the address of the host where the value of the NSEL is set to 0x00.
C. A NET address is the address of the host where the value of the NSEL is set to 0x01.
D. A NET address is the address of the host where the value of the AFI is set to 49.
|
| Answer: | A. A NET address is the address of the host where the value of the NSEL is set to 0x00.
|
| Explanation: | A NET address is the address of the host where the value of the NSEL is set to 0x00. The NSAP is the full ISO address, the NSEL field specifies the upper-layer protocol. |
|
| Question: | Which of the following statements are true about Layer 2 devices?
A. Broadcasts and multicast frames are flooded out of all ports.
B. Frames destined to an unknown location are discarded.
C. Frames destined to an unknown location are send to the default gateway.
D. Bridges and switches use a routing protocol to avoid loops.
E. Broadcasts and multicast frames are flooded out of all ports except the port it came from.
F. Bridges and switches use spanning tree to avoid loops.
|
| Answer: | E. Broadcasts and multicast frames are flooded out of all ports except the port it came from.
F. Bridges and switches use spanning tree to avoid loops.
|
| Explanation: | Layer 2 devices have the following functions:
- MAC addresses are learned from incoming frames source address
- A table of MAC addresses and their associated bridge and switch ports is build and maintained
- Broadcast and multicast frames are flooded out of all ports except the one the frame came from
- Frames destined to an unknown destination are flooded out of all ports except the one the frame came from
- Bridges and switches use spanning tree to avoid loops |
|
| Question: | How can we divide a broadcast domain?
A. Implement Layer 2 switching
B. Implement Layer 2 bridging
C. Implement VLANs
D. Implement Layer 3 routing
E. Implement Layer 3 bridging
|
| Answer: | C. Implement VLANs
D. Implement Layer 3 routing
|
| Explanation: | We can divide broadcast domains by implementing VLANs or by segmenting the network using routers or Layer 3 switches. |
|
| Question: | The traditional 80/20 rule specifies that:
A. 80 percent of network traffic is local to the segment and 20 percent is to be routed via the network backbone.
B. 20 percent of network traffic is local to the segment and 80 percent is to be routed via the network backbone.
C. 80 percent of network traffic is unicast traffic and 20 percent is broadcast/multicast traffic.
D. 20 percent of network traffic is unicast traffic and 80 percent is broadcast/multicast traffic.
|
| Answer: | A. 80 percent of network traffic is local to the segment and 20 percent is to be routed via the network backbone.
|
| Explanation: | The 80/20 rule specifies that 80 percent of the network traffic on a segment is local (switched) traffic and 20 percent of the network traffic needs to be routed via the network backbone. |
|
| Question: | What can we do if the network backbone becomes congested because of the traditional 80/20 rule?
A. Implement MLS
B. Bring resources closer to the users
C. Move all resources to 1 big datacentre
D. Move users logically (VLANs) and physically to stay near their workgroup
E. Implement faster links between the different networks
|
| Answer: | B. Bring resources closer to the users
D. Move users logically (VLANs) and physically to stay near their workgroup
|
| Explanation: | The following are a few solutions a network administrator can implement to reduce the traffic of the network backbone:
- reassign resources to bring the users and servers closer together
- move applications and files to a different server to stay within the workgroup
- move users logically and physically to stay near their workgroup
- add more servers, which can bring resources closer to the workgroups |
|
| Question: | What are the three layers of Ciscos Hierarchical Network Design?
A. Access
B. Network
C. Core
D. Backbone
E. Distribution
F. Host-to-Host
G. Internetwork
|
| Answer: | A. Access
C. Core
E. Distribution
|
| Explanation: | The three layers are: | core | backbone | | distribution | routing takes place here | | access | switching takes place here | |
|
| Question: | Which of the following functions relate to the Access layer of Ciscos hierarchical network design?
A. High throughput at Layer 3
B. High port density
C. Advanced QoS
D. Security
E. Low cost per switch port
|
| Answer: | B. High port density
E. Low cost per switch port
|
| Explanation: | The following are some capabilities of the Access layer:
- low cost per switch port
- high port density
- scalable uplinks to higher layers
- user access functions, e.g. VLAN membership, traffic and protocol filtering
- resiliency through multiple uplinks |
|
| Question: | Which of the following functions relate to the Core layer of Ciscos hierarchical network design?
A. High port density
B. Low cost per switch port
C. Security and Policy-Based connectivity
D. VLAN membership
E. High troughput on Layer 2 and 3
F. Advanced QoS
G. High availability
|
| Answer: | E. High troughput on Layer 2 and 3
F. Advanced QoS
G. High availability
|
| Explanation: | The following are some capabilities of the Core layer:
- very high througput on Layer 2 and 3
- no costly or unnecessary packet manipulations, e.g. access lists
- redundancy and resilience for high availability
- advanced QoS functions |
|
| Question: | Which of the following switches would you find at the Access layer of Ciscos hierarchical network?
A. Catalyst 4006
B. Catalyst 2950
C. Catalyst 6500
D. Catalyst 3550 (EMI)
E. Catalyst 3550 (SMI)
|
| Answer: | B. Catalyst 2950
E. Catalyst 3550 (SMI)
|
| Explanation: | The following Catalyst switches can be found at the Access layer:
- Catalyst 2950
- Catalyst 3550 SMI
- Catalyst 4000/4500 (Sup III or IV)
These are just mentioned for exam purposes in real life any Catalyst switch, IOS or CatOS, can be used at the Access layer. |
|
| Question: | If we have a remote service, i.e. different segments/VLANs, how does the traffic flows through the Cisco hierarchical network design model?
A. Access layer only.
B. From Access layer to Core layer.
C. From Access layer to Distribution layer.
D. From Distribution layer to Core layer.
|
| Answer: | C. From Access layer to Distribution layer.
|
| Explanation: | Based on the location of the network service in relation to the end user we have the following types:
| Service Type | Location of Service | Traffic Flow | | Local | Same segment/VLAN | Access layer only | | Remote | Different segment/VLAN | Access to distribution layers | | Enterprise | Central to all campus users | Access to distribution to core layers | |
|
| Question: | A switch/bridge is found at Layer ___ of the OSI model?
A. 3
B. 1
C. 6
D. 2
E. 4
|
| Answer: | D. 2
|
| Explanation: | Switches and bridges are found on Layer 2, the data link layer, of the OSI model. |
|
| Question: | In a modular network design a collection of services related to external network access is called?
A. Management block
B. Service Provider edge block
C. Core block
D. Enterprise edge block
|
| Answer: | D. Enterprise edge block
|
| Explanation: | A enterprise edge block is a collection of services related to the external network access, along with the access and distribution switches. |
|
| Question: | A switch block contains which of the following Ciscos hierarchical network design layers?
A. Access and distribution
B. distribution to core layers
C. Access only
D. Acccess to distribution to core layers
|
| Answer: | A. Access and distribution
|
| Explanation: | A switching block contains the access and distribution layers of Ciscos hierarchical network design model. |
|
| Question: | Which of the following factors should be considered when designing a switch block?
A. Type of spanning tree used
B. Traffic types
C. Speed of the uplinks
D. Size and number of workgroups
E. If the core is a dual or collapsed backbone
|
| Answer: | B. Traffic types
D. Size and number of workgroups
|
| Explanation: | When sizing a switch block take in consideration some of the following:
- traffic types and patterns
- number of users to the access layer switches
- size of spanning tree domains
- size and number of common workgroups
- geographical boundaries of subnets or VLANs |
|
| Question: | When we design the core block what are some designs we could use?
A. Backbone Core
B. ATM Core
C. Layer 3 Core
D. Dual Core
E. Collapsed Core
F. Redundant Core
|
| Answer: | D. Dual Core
E. Collapsed Core
|
| Explanation: | There are 2 basic designs of core blocks:
- Collapsed Core
- Dual Core |
|
| Question: | Which of the following resources would we find in the network management block?
A. IDS management applications
B. Enterprise Resource Planning servers
C. Mainframe systems
D. Intranet services
E. Syslog servers
F. WAN access
|
| Answer: | A. IDS management applications
E. Syslog servers
|
| Explanation: | Some of the following resources can be found in the network management block:
- network monitoring applications
- system logging servers
- authentication, authoriation and accounting servers
- policy management applications
- system administration and remote control services
- intrustion detection management applications |
|
| Question: | Which of the following resources would we find in the enterprise edge block?
A. Intranet access
B. Syslog servers
C. Corporate email
D. Internet access
E. WAN access
|
| Answer: | D. Internet access
E. WAN access
|
| Explanation: | The enterprise services that are in the enterprise edge block are usually divided in the following categories:
- internet access
- remote access and vpn
- E-commerce
- WAN access |
|
| Question: | What are some implications of using Layer 2 switches in the distribution layer?
A. STP must only run in the distribution layer.
B. The use of redundant Layer 3 links in the core is forfaited.
C. There is no need for a Layer 3 connection in the core.
D. STP must run in all layers to prevent bridging loops.
E. STP could increase the downtime when a link fails due to the unblocking or redundant links.
|
| Answer: | D. STP must run in all layers to prevent bridging loops.
E. STP could increase the downtime when a link fails due to the unblocking or redundant links.
|
| Explanation: | Some implications of using a Layer 2 distribution layer are:
- redundant Layer 3 gateways can still be used in the core
- each VLAN propogates across the redundant link from the access to the core layer, this could produce Layer 2 bridging loops
- STP must run in all layers to prevent bridging loops
- STP could increase the downtime when a link fails due to the unblocking or redundant links
- broadcast traffic reaches the core layer so bandwidth on uplinks and within the core is waisted |
|
| Question: | How does a switch provide isolation from other connected hosts?
A. Errors in frames are not propagated.
B. Each switchport notifies the other ports of errors being seen.
C. Errors in frames are minimized because of the half-duplex operation of a port.
D. Each switchport offers dedicated bandwidth.
E. Bandwidth is shared on the switching fabric.
|
| Answer: | A. Errors in frames are not propagated.
D. Each switchport offers dedicated bandwidth.
|
| Explanation: | A switch provides isolation from other hosts by the following:
- each switch port is a collision domain. - no contention on the media because of the full-duplex operation
- each switch port offers dedicated bandwidth across a switching fabric to another switch port
- errors in frames are not propagated
- broadcast traffic can be limited to a treshold
- other methods of filtering can be implemented |
|
| Question: | When a unicast frame enters the switch and the destination MAC address is not known what will happen to the frame?
A. It will be discarded by the switch.
B. It will be send to the default gateway.
C. It will be flooded out of all ports.
D. It will be discarded by the switch and an ICMP message will be send to the source.
|
| Answer: | C. It will be flooded out of all ports.
|
| Explanation: | When a unicast frame with an unknown destination MAC address enters the switch it will be flooded out of all ports, this is known as unknown unicast flooding. |
|
| Question: | The Layer 2 forwarding table is also called?
A. Content Addressable Memory
B. Cached Addressable Memory
C. Content Allocated Memory
D. Content Access Memory
|
| Answer: | A. Content Addressable Memory
|
| Explanation: | The Layer 2 forwarding table or Content Addressable Memory uses the frames destination MAC Address as an index. If the address is found, the egress switch port and the appropriate VLAN ID are read from the table. |
|
| Question: | When using a topology-based multilayer switching, this type is called?
A. Demand-based switching
B. Netflow switching
C. Cisco Express Forwarding
D. Netflow LAN switching
|
| Answer: | C. Cisco Express Forwarding
|
| Explanation: | When using topology-based MLS we also call it Cisco Express Forwarding. |
|
| Question: | Which of the following do we find in multilayer switching but not in Layer 2 switching?
A. Content Addressable Memory
B. Security ACLs
C. QoS ACLs
D. Forwarding Information Base
|
| Answer: | D. Forwarding Information Base
|
| Explanation: | The Forwarding Information Base, FIB, or Layer 3 forwarding table is found in MLS. It contains the current routing table database. |
|
| Question: | When can CEF be used to forward an IP Packet?
A. When the source and destination address is known, both Layer 2 and 3.
B. When the Layer 2 source and destination address is known.
C. When no IP parameters have to be manipulated.
D. When the packet is a CDP packet.
E. When the packet is a routing protocol update.
|
| Answer: | A. When the source and destination address is known, both Layer 2 and 3.
C. When no IP parameters have to be manipulated.
|
| Explanation: | When the source and destination address is known, both Layer 2 and 3, and no IP parameters have to be manipulated then CEF can directly forward most IP packets. |
|
| Question: | After how many seconds of idle time is an entry deleted from the CAM table?
A. 60
B. 30
C. 600
D. 900
E. 300
F. 90
|
| Answer: | E. 300
|
| Explanation: | By default an entry is deleted from the CAM table after 300 seconds of idle time. |
|
| Question: | How do we change the time a switch waits before deleting an entry from the CAM table?
A. S1(config)#mac aging-time seconds
B. S1(config)#cam-table aging-time seconds
C. S1(config)#mac address-table aging-time seconds
D. S1(config-address-table)#aging-time seconds
|
| Answer: | C. S1(config)#mac address-table aging-time seconds
|
| Explanation: | The mac address-table aging-time seconds global switch configuration command enables us to change the default aging time from 300 seconds to a more appropriate value if necessary. Prior to Catalyst IOS version 12.1 the command used to be mac-address-table aging-time seconds, the newer version omit the first hyphen. |
|
| Question: | Which of the following are part of the Ternary Content Addressable Memory?
A. Forwarding Information Base
B. Routing Database Manager
C. Filter Manager
D. Feature Manager
E. Switching Database Manager
|
| Answer: | D. Feature Manager
E. Switching Database Manager
|
| Explanation: | The 2 components part of the TCAM operation are:
- Feature Manager, compiles or merges ACE into entries in the TCAM table
- Switching Database Manager, when the TCAM is partitioned into different functions this configures or tunes those partitions |
|
| Question: | How do we configure a permanent entry in the CAM table?
A. S1(config)#mac address-table mac_address vlan vlan_id interface type mod/port
B. S1(config-address-tabel)#mac_address vlan vlan_id interface type mod/port
C. S1(config)#mac address-table mac_address vlan vlan_id interface type mod/port permanent
D. S1(config)#mac address-table static mac_address vlan vlan_id interface type mod/port
|
| Answer: | D. S1(config)#mac address-table static mac_address vlan vlan_id interface type mod/port
|
| Explanation: | To enter a permanent entry in the CAM table we use the mac address-table static mac_address vlan vlan_id interface type mod/port global switch configuration command.
Prior to Catalyst IOS version 12.1 the command used to be mac-address-table static mac_address vlan vlan_id interface type mod/port, the newer version omit the first hyphen. |
|
| Question: | Which of the following are part of a TCAM entry?
A. Weight
B. MAC Address
C. Age
D. Value
E. Mask
F. Result
G. Length
|
| Answer: | D. Value
E. Mask
F. Result
|
| Explanation: | TCAM entries are composed of Value, Mask and Result combinations. |
|
| Question: | How do we display the CAM table?
A. show cam
B. show mac-table
C. show address-table
D. show mac address-table dynamic
|
| Answer: | D. show mac address-table dynamic
|
| Explanation: | The show mac address-table dynamic command will display the CAM table. |
|
| Question: | Which command can we use to display the TCAM partitions?
A. show tcam partitions
B. show memory partitions
C. show sdm prefer
D. show sdm partitions
|
| Answer: | C. show sdm prefer
|
| Explanation: | The show sdm prefer command will display the current TCAM partitioning. |
|
| Question: | How do we change the name of the switch?
A. S1(config)#hostname name
B. S1#hostname name
C. S1(config-switch)#hostname name
D. S1(config)>hostname name
|
| Answer: | A. S1(config)#hostname name
|
| Explanation: | As on a Cisco router, the hostname global configuration command will change the name of the switch. |
|
| Question: | How do we set a password on all vty lines?
A. S1(config)#line vty 0 15 S1(config-line)#password password
B. S1(config)#line vty 0 4 S1(config-line)#password password
C. S1(config)#line vty S1(config-line)#password password
D. S1(config)#line vty all S1(config-line)#password password
|
| Answer: | A. S1(config)#line vty 0 15 S1(config-line)#password password
|
| Explanation: | To set a login password on all the vty lines, 0 15, we use the password password line configuration command. |
|
| Question: | How do we assign a default gateway to the default management VLAN?
A. S1(config)#interface vlan 1 S1(config-if)#ip default-gateway ip_address
B. S1(config)#interface vlan 1 S1(config-vlan)#ip default-gateway ip_address
C. S1(config)#interface vlan 1 S1(config-if)#ip route 0.0.0.0 0.0.0.0 next_hop
D. S1(config)#ip default-gateway ip_address
|
| Answer: | A. S1(config)#interface vlan 1 S1(config-if)#ip default-gateway ip_address
|
| Explanation: | The default management VLAN is VLAN 1. We use the ip default-gateway ip_address interface configuration command to assign a default gateway to the switch. Together with an IP_Address this will allow for remote access of the switch. |
|
| Question: | How do we disable CDP on a switch port?
A. S1(config)#no cdp run interface type mod/port
B. S1(config-if)#no cdp run
C. S1(config-if)#cdp disable
D. S1(config-if)#no cdp enable
|
| Answer: | D. S1(config-if)#no cdp enable
|
| Explanation: | CDP is enabled by default on all switch interfaces. To disable CDP we use the no cdp enable interface configuration command. |
|
| Question: | If the flash memory is corrupted what can be done to repair it?
A. erase flash:
B. delete flash:
C. defrag flash:
D. sqeeze flash:
E. format flash:
|
| Answer: | E. format flash:
|
| Explanation: | Using the format flash command will reformat the flash memory, destroying all files. This could be appropriate when the flash memory has been corrupted. |
|
| Question: | What command can we use to check that an IOS image is not corrupted after being copied into flash memory?
A. check flash:filename
B. more flash:filename
C. show flash:filename
D. verify flash:filename
|
| Answer: | D. verify flash:filename
|
| Explanation: | The verify flash:filename command will check the checksum of the file, e.g.IOS name to ensure that this hasnt been corrupted after it has been copied into flash memory. |
|
| Question: | How do we display a summary of the neighbor switch names and management IP addresses?
A. show cdp neighbors *
B. show cdp entry summary
C. show cdp neighbors summary
D. show cdp neighbors brief
E. show cdp entry * protocol
|
| Answer: | E. show cdp entry * protocol
|
| Explanation: | The show cdp entry * protocol command will display a brief summary of only the neighbors switch names and management IP Addresses. |
|
| Question: | How do we clear the CDP cache?
A. clear cdp entries *
B. clear cdp cache
C. clear cdp table
D. clear cdp neighbors
|
| Answer: | C. clear cdp table
|
| Explanation: | The clear cdp table command will clear the CDP cache to see what new information is being received from the neighbors. |
|
| Question: | What command will display the current running environment and IOS version?
A. show running-config
B. show module
C. show history
D. show version
E. show config
|
| Answer: | D. show version
|
| Explanation: | The show version command will display the current running environment and the IOS version. |
|
| Question: | When using LRE over a distance of 5000 feet what is the maximum full-duplex bandwidth?
A. 5 Mbps
B. 10 Mbps
C. 100 Mbps
D. 15 Mbps
E. 1000 Mbps
|
| Answer: | A. 5 Mbps
|
| Explanation: | LRE or Long Reach Ethernet has to the following bandwidth restrictions:
- 5 Mbps full-duplex up to 5000 feet
- 10 Mbps full-duplex up to 4000 feet
- 15 Mbps full-duplex up to 3000 feet |
|
| Question: | In autonegotiation 100Base-TX uses which priority?
A. 5
B. 6
C. 7
D. 3
E. 1
F. 2
G. 4
|
| Answer: | D. 3
|
| Explanation: | | Priority | Ethernet media | | 7 | 100BASE-T2 Full Duplex | | 6 | 100BASE-TX Full Duplex | | 5 | 100BASE-T2 Half Duplex | | 4 | 100BASE-T4 | | 3 | 100BASE-TX | | 2 | 10BASE-T Full Duplex | | 1 | 10BASE-T | |
|
| Question: | 1000BASE-T is based on which IEEE standard?
A. 802.3
B. 802.1Q
C. 802.3ab
D. 802.3z
|
| Answer: | C. 802.3ab
|
| Explanation: | 1000BASE-T or "Gigabit over copper" is based on the IEEE 802.3ab standard. |
|
| Question: | How can we assign common configuration settings to multiple switch ports?
A. S1(config-if)#interface range type module/first_port last_port
B. S1(config)#port range type module/first_port last_port
C. S1(config)#interface-range type module/first_port last_port
D. S1(config)#interface range type module/first_port last_port
E. S1(config-if)#range type module/first_port last_port
|
| Answer: | D. S1(config)#interface range type module/first_port last_port
|
| Explanation: | To assign common configuration settings to multiple switchports we use the interface range type module/first_port last_port global configuration command. |
|
| Question: | We want to disable a port when an error is detected. How do we configure the switch?
A. S1(config)#errdisable detect cause all
B. S1(config-if)#disable detect cause all
C. S1(config)#errdisable cause all
D. S1(config-if)#errdisable detect cause all
|
| Answer: | A. S1(config)#errdisable detect cause all
|
| Explanation: | We use the errdisable detect cause [all | cause_name] global configuration command to disable a switchport when an error condition is detected. |
|
| Question: | For testing purposes we need to change the configuration numerous times on multiple switch ports. How can we make do and undo these changes easily?
A. Create a macro with the command with the define macro_nameint_type/first_port last_port command.
B. Create a macro with the command with the macro interface range macro_name int_type/first_port last_port command.
C. Create a macro with the command with the define macro_name interface range int_type/first_port last_port command.
D. Create a macro with the command with the define interface range macro_name int_type/first_port last_port command.
|
| Answer: | D. Create a macro with the command with the define interface range macro_name int_type/first_port last_port command.
|
| Explanation: | If we need to make multiple configuration changes on the same switch for testing purposes and undo them we can define macros that contain those commands. We use the define interface range macro_name int_type/first_port last_port global configuration command. |
|
| Question: | When a switch port is configured for being disabled on an error condition and automatic recovery how do assign the time that the port is disabled?
A. S1(config-if)#errdisable recovery interval seconds
B. S1(config)#recovery interval seconds
C. S1(config)#errdisable recovery interval seconds cause all
D. S1(config)#errdisable recovery interval seconds
|
| Answer: | D. S1(config)#errdisable recovery interval seconds
|
| Explanation: | When a errdisable causes are configured for automatic recovery we can set the time a swith port remains disable with the errdisable recovery interval seconds global configuration command. The default time is 300 seconds. |
|
| Question: | How can we see a list of all ports that are in errdisable state?
A. show interface status err-disabled
B. show interface errdisabled
C. show errdisabled
D. show status errdisabled
|
| Answer: | A. show interface status err-disabled
|
| Explanation: | To view a list of all ports in errdisable state we use the show interface status err-disabled command. |
|
| Question: | Which of the following will not trigger a errdisable state?
A. colguard
B. duplex-flap
C. pagp-flap
D. all
E. rootguard
|
| Answer: | A. colguard
B. duplex-flap
|
| Explanation: | An errdisable state can be triggered by one of the following:
- all
- bpduguard
- dtp-flap
- link-flap
- pagp-flap
- rootguard
- udld |
|
| Question: | How can we bring a switch port manually out of errdisable state?
A. Perform a shutdown and no shutdown on the interface.
B. Use the no errdisable command.
C. Perform a clear interface command.
D. If errdisable is configured it has to remain in that state untill the recovery time interval has elapsed.
|
| Answer: | A. Perform a shutdown and no shutdown on the interface.
|
| Explanation: | To manually recover a switch port from an errdisable state we use the shutdown and no shutdown interface configuration command to "bounce" the interface. |
|
| Question: | Static VLANs offer membership based on?
A. host-based
B. MAC address based
C. Priority based
D. port-based
|
| Answer: | D. port-based
|
| Explanation: | Static VLAN membership is port-based, switch ports are assigned to a specific VLAN. |
|
| Question: | How do we configure a static VLAN on S1?
A. S1#vlan vlan_numb
B. S1(config)#vlan S1(config-vlan)#vlan vlan_numb
C. S1(config)#vlan vlan_numb
D. S1(config-if)#switchport access vlan vlan_numb
|
| Answer: | C. S1(config)#vlan vlan_numb
|
| Explanation: | To configure a static VLAN we use the vlan vlan_number global configuration command. |
|
| Question: | Dynamic VLANs use __________ to provide membership.
A. MAC Addresses
B. Hostnames
C. Switch ports
D. IP Addresses
|
| Answer: | A. MAC Addresses
|
| Explanation: | Dynamic VLANs provide membership based on MAC Addresses. These MAC Addresses have to be entered in the database of the VMPS, VLAN Membership Policy Server. |
|
| Question: | Which type of VLANs should we implement if we want to follow the 80/20 rule?
A. End-to-End
B. Local
C. Transparent
D. Dynamic
|
| Answer: | A. End-to-End
|
| Explanation: | End-to-End VLANs group the users by common requirements, i.e. the users have the same traffic flow pattern. The 80/20 rule states that 80 percent of the traffic is local to the workgroup so end-to-end VLANs are ideal for this situation. It is worth mentioning that end-to-end VLANs are not recommended because broadcast traffic will traverse the entire network. |
|
| Question: | Which protocols can we use to identify VLANs?
A. ISL
B. 802.1Q
C. VTP
D. 802.1D
E. STP
|
| Answer: | A. ISL
B. 802.1Q
|
| Explanation: | VLAN identification can use one of the following protocols:
- ISL, Inter-Switch Link [Cisco proprietary]
- 802.1Q, an IEEE standard |
|
| Question: | When using 802.1Q and there is no tagging on the frame, the frame belongs to the ______ VLAN.
A. universal
B. native
C. default
D. common
E. first
|
| Answer: | B. native
|
| Explanation: | When using 802.1Q, frames that belong to the native VLAN are not encapsulated with any tagging information. |
|
| Question: | Which of the following are part of the 4 bytes that 802.1Q adds to the frame?
A. DSCP
B. CoS
C. TPID
D. CRC
E. FIB
F. TCI
|
| Answer: | C. TPID
F. TCI
|
| Explanation: | The first two bytes are used for the Tag Protocol Identifier (TPID) and the last 2 bytes are used for the Tag Control Information (TCI). |
|
| Question: | How do we configure the trunk to allow only vlan 5 to be trunked?
A. S1(config-if)#switchport trunk vlan 5
B. S1(config-if)#switchport trunk except vlan 5
C. S1(config-if)#switchport trunk allowed vlan 5
D. S1(config-if)#switchport mode trunk allowed vlan 5
|
| Answer: | C. S1(config-if)#switchport trunk allowed vlan 5
|
| Explanation: | The switchport trunk allowed vlan vlan_list interface configuration command defines which VLANs can be trunked over the link, by default all VLANs, 1 to 4094, are allowed over the link. |
|
| Question: | Changing the bandwidth on an EIGRP enabled interface will have which of the following results?
A. Changes the state of interface
B. Changes the amount of EIGRP traffic sent over the link
C. Changes the K3 value and therefore the metric calculation.
D. Changes the K1 value and therefore the metric calculation.
E. Changes the priority of EIGRP traffic sent over the link
|
| Answer: | B. Changes the amount of EIGRP traffic sent over the link
D. Changes the K1 value and therefore the metric calculation.
|
| Explanation: | By changing the bandwidth statement on an EIGRP interface we change the K1 value and that will result in a new metric calculation. Beause by default EIGRP uses 50% of the available bandwidth for its own traffic that change will result in a change here as well. |
|
| Question: | Which of the following are components of EIGRP?
A. Attributes
B. Authentication
C. Protocol-dependent modules
D. Protocol-independent modules
E. Neighbor recovery
F. Peer groups
|
| Answer: | C. Protocol-dependent modules
E. Neighbor recovery
|
| Explanation: | Cisco identifies 4 main components of EIGRP:
- Protocol-dependent modules
- RTP
- Neighbor discovery
- Neighbor recovery
|
|
| Question: | Which of the following statements are true when configuring EIGRP over a NBMA network?
A. Bandwidth allocated to EIGRP can be different in both directions on each VC.
B. EIGRP traffic should not exceed the CIR of the VC.
C. EIGRP traffic should not exceed the EIR of the VC.
D. Bandwidth allocated to EIGRP must be the same in both directions on each VC.
E. EIGRP aggregated traffic over all VCs can be more then the access line speed of the interface.
|
| Answer: | B. EIGRP traffic should not exceed the CIR of the VC.
D. Bandwidth allocated to EIGRP must be the same in both directions on each VC.
|
| Explanation: | When configuring EIGRP over a NBMA cloud Cisco recommends you follow the following rules:
- EIGRP traffic should not exceed the CIR capacity of the VC
- EIGRP aggregated traffic over all VCs should not exceed the access line speed of the interface
- Bandwidth allocated to EIGRP on each VC must be the same in both directions |
|
| Question: | How do we verify if a remote router is configured as a stub with EIGRP?
A. show ip eigrp topology
B. show ip eigrp stub
C. show ip eigrp interface
D. show ip eigrp database
E. show ip eigrp neighbor detail
|
| Answer: | E. show ip eigrp neighbor detail
|
| Explanation: | Router# show ip eigrp neighbors detail
IP-EIGRP neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq Tye
(sec) (ms) Cnt Num
0 10.1.1.5 Et0/0 12 00:04:48 1832 5000 0 14
Version 12.2/1.2, Retrans:0, Retries:0
Restart time 00:01:05
Stub Peer Advertising ( CONNECTED SUMMARY ) Routes
|
|
| Question: | Which of the following keywords are not used with the EIGRP stub command?
A. receive-only
B. connected
C. static
D. send-only
E. total
F. no-summary
|
| Answer: | D. send-only
E. total
F. no-summary
|
| Explanation: | The EIGRP stub command has the following keywords:
- receive-only, the neighbor is a receive-only router
- connected, the neighbor advertises connected routes
- static, the neighbor advertises static routes
- summary, the neighbor advertises summary routes
|
|
| Question: | We want to change the time a router waits without hearing a Hello from the its neighbor before declaring it unavailable. How do we achieve this?
A. R1(config)#interface ethernet 0 R1(config-if)#ip hold-timer eigrp 10 100
B. R1(config)#interface ethernet 0 R1(config-if)#ip eigrp hold-interval 10 100
C. R1(config)#interface ethernet 0 R1(config-if)#ip eigrp hold-time 10 100
D. R1(config)#interface ethernet 0 R1(config-if)#ip hold-time eigrp 10 100
E. R1(config)#interface ethernet 0 R1(config-if)#ip hold-interval eigrp 10 100
|
| Answer: | D. R1(config)#interface ethernet 0 R1(config-if)#ip hold-time eigrp 10 100
|
| Explanation: | We use the ip hold-time eigrp AS_nr seconds interface configuration command to change the time a router waits without hearing a Hello from a neighbor before declaring that neighbor unavailable. |
|
| Question: | When can we turn off synchronization in BGP?
A. When the network is partial meshed.
B. When the network is not running an IGP.
C. When the local preference attribute is set.
D. When the network is fully meshed.
|
| Answer: | D. When the network is fully meshed.
|
| Explanation: | Synchronization can be turned off if the BGP network is fully meshed. |
|
| Question: | Which attribute is created by a route reflector?
A. Origin
B. Community
C. Multiple Exit Discriminator
D. Originator-ID
|
| Answer: | D. Originator-ID
|
| Explanation: | The optional nontransitive attribute Originator-ID is created by the route reflector. The attribute contains the RID of the router that originated the update and is used to prevent routing loops. |
|
| Question: | When would you not use BGP?
A. When you are using multiple ISPs.
B. The routing policy between you and the ISP is the same.
C. There is a difference in routing policy between you and the ISP.
D. There are limited resources on the router.
E. Your AS will be a transit domain.
|
| Answer: | B. The routing policy between you and the ISP is the same.
D. There are limited resources on the router.
|
| Explanation: | The following are some statements when not to use BGP:
- the organization and ISP use the same routing policy
- multiple redundant links to the ISP but only 1 link will be activated to connect to the Internet
- the routers have limited resources (CPU, memory)
- low bandwidth between the organization and ISP causing the additional routing overhead to interfere with the data |
|
| Question: | Which BGP message is used to inform a peer an error occured?
A. Notification
B. Keepalive
C. Update
D. Open
|
| Answer: | A. Notification
|
| Explanation: | BGP uses the notification message to inform the receiving router of errors that cause the connection to be closed. |
|
| Question: | Which of the following AS numbers are part of the private pool described by RFC 2270?
A. 19200
B. 65510
C. 56412
D. 65560
E. 6600
F. 65495
G. 32123
|
| Answer: | B. 65510
F. 65495
|
| Explanation: | The private AS pool ranges from 64512 - 65535. |
|
| Question: | Which of the following describes best the synchronization rule in BGP?
A. A router cannot forward a route to an iBGP peer unless the route is in the local IP routing table.
B. A router can forward a route to an eBGP peer unless the route is in the local IP routing table.
C. A router can forward a route to an iBGP peer unless the route is in the local IP routing table.
D. A router is synchronized when the iBGP table is the same as the eBGP table.
E. A router cannot forward a route to an eBGP peer unless the route is in the local IP routing table.
|
| Answer: | E. A router cannot forward a route to an eBGP peer unless the route is in the local IP routing table.
|
| Explanation: | The synchronization rule states that a router cannot forward a route to an eBGP peer unless the route is in its local IP routing table. This requires the IGP and BGP to be synchronized and prevents BGP from advertising routes that the AS cannot direct to the destination. |
|
| Question: | Which of the following rules about policy based routing are true?
A. Policy based routing can influence how a packet will be routed in a neighboring AS.
B. Policy based routing affects only the next hop in the path to the destination.
C. Policy based routing affects the destination of the packet.
D. Policy based routing examines the source address and should be configured on the inbound interface.
E. Policy based routing examines the source address and should be configured on the outbound interface.
F. Policy based routing examines the destination address only and should be configured on the inbound interface.
|
| Answer: | B. Policy based routing affects only the next hop in the path to the destination.
D. Policy based routing examines the source address and should be configured on the inbound interface.
|
| Explanation: | Some rules of policy based routing:
- traffic can be directed on source address or both source & destination address
- affects only the next hop in the path to the destination
- does not affect the destination of the packet, only that path to get there
- does not allow traffic sent into another AS to take a different path from the one that would have been chosen by that AS
- it is possible to influence traffic how to get to a neighboring AS not how it will be routed within that AS
- examines the source address so its configured on the inbound interface |
|
| Question: | Which of the following attributes are optional transitive?
A. Aggregator
B. Community
C. AS_Path
D. Atomic aggregate
E. Originator ID
F. Cluster ID
G. Weight
|
| Answer: | A. Aggregator
B. Community
|
| Explanation: | BGP has the following optional transitive attributes:
- Aggregator
- Community |
|
| Question: | Which attribute can cause problems on a multiaccess network?
A. Origin
B. Next hop
C. Community
D. Aggregator
E. AS_Path
|
| Answer: | B. Next hop
|
| Explanation: | In eBGP, the next hop is the IP Address, specified in the neighbor command, of a router from outside the AS advertising into the AS. On a multiaccess network, if a route came from one router, it would be unwise for another router to advertise that route with its own IP Address as the source, this could lead to packets flooding the network before finding the true originator. The rule therefore is that the address of the router the originally sent the update onto the multiaccess network should remain the source address. |
|
| Question: | Which attributes are not required but if they are in an update all routers running BGP will recognize and act on the information contained?
A. Aggregator
B. Atomic Aggregate
C. AS_Path
D. Community
E. Next hop
F. Local Preference
G. Origin
|
| Answer: | B. Atomic Aggregate
F. Local Preference
|
| Explanation: | A well-known discretionary attribute is not required but when its present in an update all routers running BGP will recognize and act on the information contained. There are the following well-known discretionary attributes:
- local preference
- atomic aggregate |
|
| Question: | How can we simplify configuration of multiple neighbors?
A. R1(config-router)#neighbor free-tests peer-group R1(config-router)#neighbor free-tests update-source loopback 0 R1(config-router)#neighbor 10.1.1.1 remote-as 123 R1(config-router)#neighbor 10.1.1.1 peer-group free-tests R1(config-router)#neighbor 192.168.1.1 remote-as 456 R1(config-router)#neighbor 192.168.1.1 peer-group free-tests
B. R1(config-router)#neighbor 10.1.1.1 free-tests R1(config-router)#neighbor 10.1.1.1 remote-as 123 R1(config-router)#neighbor 192.168.1.1 free-tests R1(config-router)#neighbor 192.168.1.1 remote-as 456
C. R1(config-router)#neighbor free-tests peer-group R1(config-router)#neighbor free-tests update-source loopback 0 R1(config-router)#neighbor 10.1.1.1 remote-as 123 peer-group R1(config-router)#neighbor 192.168.1.1 remote-as 456 peer-group
D. R1(config-router)#neighbor peer-group free-tests R1(config-router)#neighbor 10.1.1.1 free-tests R1(config-router)#neighbor 10.1.1.1 remote-as 123 R1(config-router)#neighbor 192.168.1.1 free-tests R1(config-router)#neighbor 192.168.1.1 remote-as 456
|
| Answer: | A. R1(config-router)#neighbor free-tests peer-group R1(config-router)#neighbor free-tests update-source loopback 0 R1(config-router)#neighbor 10.1.1.1 remote-as 123 R1(config-router)#neighbor 10.1.1.1 peer-group free-tests R1(config-router)#neighbor 192.168.1.1 remote-as 456 R1(config-router)#neighbor 192.168.1.1 peer-group free-tests
|
| Explanation: | We can simplify configuration by grouping neighbors that share the same update policy in a peer group.
To use a peer group we follow these steps:
- Create the peer group, neighbor peer_group_name peer-group
- Assign options to the peer group, neighbor peer_group_name option
- Make neighbors member of the peer group, neighbor IP_address peer-group peer_group_name |
|
| Question: | We want to advertise an aggregate route route for 170.0.0.0 but surpress any specific routes. How do we achieve this?
A. aggregate-address 170.0.0.0 255.0.0.0 summary-only
B. aggregate-address 170.0.0.0 255.0.0.0
C. aggregate-address 170.0.0.0 255.0.0.0 only
D. summary-address 170.0.0.0 255.0.0.0
|
| Answer: | A. aggregate-address 170.0.0.0 255.0.0.0 summary-only
|
| Explanation: | To advertise a summary route we use the aggregate-address IP_Address Mask command. Adding the summary-only keyword will surpress ther advertisment of more specific routes to all neighbors. |
|
| Question: | Which command will show the BGP routing table?
A. show bgp neighbors
B. show ip bgp
C. show ip route bgp
D. show ip bgp route
|
| Answer: | B. show ip bgp
|
| Explanation: | The show ip bgp command will display the BGP routing table. |
|
| Question: | Which command will show the BGP topology?
A. show ip bgp paths
B. show ip bgp topology
C. show ip bgp database
D. show ip bgp
|
| Answer: | A. show ip bgp paths
|
| Explanation: | The show ip bgp paths command will display the BGP topology. |
|
| Question: | Which command can we use to make sure that the source address of the route is the transmitting router in BGP?
A. neighbor IP_Address always
B. neighbor IP_Address mask mask next-hop-self
C. neighbor IP_Address next-hop-self
D. neighbor IP_Address remote-as next-hop-self
|
| Answer: | C. neighbor IP_Address next-hop-self
|
| Explanation: | The neighbor IP_Address next-hop-self router configuration command makes sure that the source address of the transmitting router will remain the same when the route is injected on a multiaccess network. |
|
| Question: | Besides having a fully meshed network what could be other reasons to turn off synchronization in BGP?
A. When all routers in the AS are running BGP.
B. When the AS is not a transist AS.
C. When the AS is a transit AS.
D. When the routers at the egress and ingress point are running BGP.
E. When no routes are redistributed into the AS.
|
| Answer: | A. When all routers in the AS are running BGP.
B. When the AS is not a transist AS.
|
| Explanation: | Synchronization can be turned off in BGP when:
- all routers in the AS run BGP
- the AS is not a transit AS
- all the routers inside the AS are meshed |
|
| Question: | How do we turn off synchronization in BGP?
A. R1(config-router)#no synchronization
B. R1(config-router)#no auto-summary
C. R1(config-router)#neighbor ip_address no synchronization
D. R1(config-if)#no synchronization
E. R1(config-router)#no summarization
|
| Answer: | A. R1(config-router)#no synchronization
|
| Explanation: | To turn off synchronization we use the no synchronization router configuration command. |
|
| Question: | When there are multiple route reflectors which attribute is used to identify the originating router?
A. Cluster-ID
B. Origin
C. Originator-ID
D. AS_Path
E. MED
|
| Answer: | A. Cluster-ID
|
| Explanation: | When there are multiple route reflectors in the cluster to provide redundancy the originating router is identified by the Cluster-ID attribute. This attribute is used to prevent routing loops. |
|
| Question: | When a router is configured to forward routing updates to neighbors or peers in the same BGP AS it is called a _____________ ?
A. confederation
B. BGP peering session
C. adjacency
D. route reflector
|
| Answer: | D. route reflector
|
| Explanation: | A route reflector is a router configured to forward routing updates to neighbors or peers within the same AS. |
|
| Question: | The split horizon rule in BGP states?
A. Updates learned from iBGP peers are not send to other iBGP peers.
B. Updates learned from eBGP peers are not send to other eBGP peers.
C. Only prefixes are redistributed to other iBGP systems.
D. There is no split horizon rule in BGP since all neighbors are configured manually.
|
| Answer: | A. Updates learned from iBGP peers are not send to other iBGP peers.
|
| Explanation: | The split horizon rule states that no updates learned from iBGP peers can be sent to other iBGP peers and therefore avoid routing loops. |
|
| Question: | What are benefits of the BGP synchronization rule?
A. reduces network resources
B. consistency within the AS
C. reduces routing updates
D. reduces unnecessary traffic
E. removes the need for an IGP
|
| Answer: | B. consistency within the AS
D. reduces unnecessary traffic
|
| Explanation: | A few benefits of synchronization are:
- prevents traffic from being forwarded to unreachable destinations
- reduces unnecessary traffic
- ensures consistency within the AS |
|
| Question: | When will an iBGP router propogate a route to a BGP neighbor?
A. When the route is redistributed from an IGP.
B. When the network command is used.
C. When the route is received from another iBGP router.
D. When the route is summarized.
E. When the route has the longest prefix match of all paths to the destination.
|
| Answer: | A. When the route is redistributed from an IGP.
B. When the network command is used.
|
| Explanation: | An iBGP router will propagate a route to another BGP neighbor when: - the advertised route was generated by the transmitting router via one of the following methods: - via the network command - redistributed from an IGP - redistributed static routes - the advertised route is a connected route |
|
| Question: | Which of the following are benefits of using route reflectors?
A. reduction of network traffic
B. faster convergence
C. no need for an IGP
D. no need for synchronization within the AS
|
| Answer: | A. reduction of network traffic
B. faster convergence
|
| Explanation: | Some benefits of route reflectors are: - improved scalability of the network - strong hierarchical design - reduction of network traffic - reduction of memory and CPU resources - faster convergence |
|
| Question: | How do we configure a route reflector?
A. R1(config-router)#neighbor ip_address route-reflector
B. R1(config-router)#neighbor ip_address route-reflector-client remote-as AS_number
C. R1(config-router)#neighbor ip_address route-reflector remote-as AS_number
D. R1(config-router)#network ip_address route-reflector-client remote-as AS_number
E. R1(config-router)#neighbor ip_address route-reflector-client
|
| Answer: | E. R1(config-router)#neighbor ip_address route-reflector-client
|
| Explanation: | To configure a route reflector we use the neighbor ip_address router-reflector-client router configuration command. |
|
| Question: | We want to send a full BGP update to a specific peer. How do we achieve this?
A. R1#clear ip route bgp
B. R1#clear ip bgp ip_address out
C. R1#clear ip bgp ip_address in
D. R1#clear ip bgp *
|
| Answer: | B. R1#clear ip bgp ip_address out
|
| Explanation: | In order to let the BGP routing process send a full update to a peer we use the clear ip bgp neighbor_address out command. |
|
| Question: | How do we configure the router so that BGP peering sessions are not torn down when new configurations are implemented?
A. R1(config-router)#neighbor neighbor_address soft-configuration inbound
B. R1(config-router)#neighbor neighbor_address soft-configuration
C. R1(config-router)#neighbor neighbor_address configuration inbound
D. R1(config-router)#neighbor neighbor_address soft-inbound
|
| Answer: | A. R1(config-router)#neighbor neighbor_address soft-configuration inbound
|
| Explanation: | We can configure BGP to store the prefixes before the policy application.
This requires more memory but allows new configurations to be implemented without tearing down the BGP peering sessions.
In order to achieve this we use the neighbor neighbor_address soft-configuration inbound router configuration command.
Because this is on a per-neighbor basis and only for inbound updates we use the inbound keyword. |
|
| Question: | Why would we use policy-based routing in BGP?
A. To make decisions based on Next-Hop and Origin attribute.
B. To make decisions based on router resources.
C. To reject or accept selected routes.
D. To set attributes to influence path selection.
|
| Answer: | C. To reject or accept selected routes.
D. To set attributes to influence path selection.
|
| Explanation: | Reasons for applying policy-based routing in BGP are:
- to make decision based on AS Path, Community or the prefix
- to reject or accept select routes
- to set attributes to influence the path selection |
|
| Question: | Which of the following statements are true about prefix lists?
A. There is no implicit deny at the bottom of every prefix list.
B. When there are multiple entries in the prefix list that match the prefix the highest sequence number is used.
C. Sequence numbers have to be manually configured.
D. If a route is permitted then the route is used.
E. A sequence number does not need to be specified when removing an entry.
|
| Answer: | D. If a route is permitted then the route is used.
E. A sequence number does not need to be specified when removing an entry.
|
| Explanation: | Prefix permitting or denying is based on the following rules:
- if the route is permitted it is used
- if the route is denied it is not used
- there is an implicit deny any at the bottom of every prefix list
- when multiple entries of a prefix list match a given prefix, the entry with the smallest sequence number is used
- the router begins the search for a match at the top of the prefix list, if a match is made the search stop
- sequence numbers are automatically generated by default
- sequence numbers do not need to be specified when removing a configuraton entry |
|
| Question: | Which prefix list parameter do we use when the prefix is greater than or equal to the value stated in the list?
A. le
B. len
C. ge
D. seq
|
| Answer: | C. ge
|
| Explanation: | The ge parameter is used if the prefix is greater than or equal to the value stated in the list. |
|
| Question: | How do we configure R1 to allow 10.1.0.0/16 to be processed by BGP?
A. R1(config-router)#neighbor ip_address prefix-list allowed in R1(config-if)#ip prefix-list allowed permit 10.1.0.0/16
B. R1(config-router)#neighbor ip_address prefix-list allowed in R1(config-router)#ip prefix-list allowed permit 10.1.0.0 255.255.0.0
C. R1(config-router)#neighbor ip_address prefix-list allowed in R1(config-router)#ip prefix-list permit 10.1.0.0/16
D. R1(config-router)#neighbor ip_address prefix-list allowed in R1(config)#ip prefix-list allowed permit 10.1.0.0/16
|
| Answer: | D. R1(config-router)#neighbor ip_address prefix-list allowed in R1(config)#ip prefix-list allowed permit 10.1.0.0/16
|
| Explanation: | To configure a router to use a prefix list as a filter in distributing routes we use the neighbor ip_address prefix-list prefix_list_name in | out router configuration command. To configure the prefix list we use the ip prefix-list name deny | permit network/len global configuration command. |
|
| Question: | We want to know if there are any matches against our configured prefix lists. Which command do we use?
A. show bgp prefix-list detail
B. show ip bgp prefix-list summary
C. show ip bgp prefix-list
D. show bgp prefix-list
E. show ip prefix-list detail
|
| Answer: | E. show ip prefix-list detail
|
| Explanation: | R1# show ip prefix-list detail allowed
ip prefix-list allowed:
Description: allowed-list
count: 1, range entries: 0, sequences: 10 - 10, refcount: 3
seq 10 permit 10.0.0.0/8 (hit count: 0, refcount: 1) |
|
| Question: | We want to create a prefix list that denies all prefixes between 192.168.1.0/20 and 192.168.1.0/24. How do we achieve this?
A. ip prefix-list test deny 192.168.1.0 ge 20 le 24
B. ip prefix-list test deny 192.168.1.0/24 ge 20
C. ip prefix-list test deny 192.168.1.0/24 le 20
D. ip prefix-list test deny 192.168.1.0/20 le 24
E. ip prefix-list test deny 192.168.1.0/20 ge 24
|
| Answer: | D. ip prefix-list test deny 192.168.1.0/20 le 24
|
| Explanation: | When there is no ge value specified the prefix list uses only the prefixes between the len value and the le value. If no ge and le value is specified an exact match is assumed. |
|
| Question: | If we want to allow all prefixes between /8 and /16 how do we configure the prefix-list?
A. ip prefix-list test permit 0.0.0.0/0 le 16 ge 8
B. ip prefix-list test permit 0.0.0.0 ge 8 le 16
C. ip prefix-list test permit 0.0.0.0/0 le 16
D. ip prefix-list test permit 0.0.0.0/0 ge 8 le 16
|
| Answer: | D. ip prefix-list test permit 0.0.0.0/0 ge 8 le 16
|
| Explanation: | In order to allow all prefixes between /8 and /16 we use the ip prefix-list prefix_list_name permit 0.0.0.0/0 ge 8 le 16 router configuration command. The ge value is the lower limit so the allowed/denied prefixes have to be greater in value then the ge value but smaller then the le value. Therefore we can say the le value is the upper limit for the prefixes. |
|
| Question: | In a multihomed AS and accepting only the default route from the ISPs how does BGP select the best path to the external network?
A. By using the AS_Path attribute that selects the exit path to the Internet.
B. By using the Originator-ID attribute that selects the exit path to the Internet.
C. By using the gateway that advertised the route.
D. By using the gateway with highest local-preference attribute.
|
| Answer: | C. By using the gateway that advertised the route.
|
| Explanation: | In a multihomed AS and accepting only the default route from the ISPs BGP select the best path to the external network by using the gateway that is advertising the route. |
|
| Question: | If there are multiple paths to the same destination how can we influence them using the Ciscos proprietary attribute?
A. R1(config-router)#neighbor ip_address remote-as as_number weight value
B. R1(config-router)#neighbor ip_address med value
C. R1(config-router)#neighbor ip_address weight value
D. R1(config-router)#neighbor ip_address local-preference value
|
| Answer: | C. R1(config-router)#neighbor ip_address weight value
|
| Explanation: | Weight is Ciscos proprietary attribute in BGP. The higher the value of this attribute the better the path. We use the neighbor ip_address weight value router configuration command to change the weight attribute. The default value is 32768 and the range extends from 0 to 65535. |
|
| Question: | Besides the weight attribute we can use another attribute to influence the path out of the AS when we have multiple paths. How do we achieve this?
A. bgp local-preference value
B. bgp default AS_Path value
C. bgp default local-preference value
D. bgp default next-hop ip_address
|
| Answer: | C. bgp default local-preference value
|
| Explanation: | We can use the bgp default local-preference router configuration command to inform the routers iBGP peers of the preferred exit path from the AS when there are multiple paths. The default value is 100. |
|
| Question: | How can we verify that certain BGP attributes (e.g. weight) have changed after configuration?
A. show bgp attributes
B. show ip bgp attributes
C. show ip bgp
D. show ip bgp summary
|
| Answer: | C. show ip bgp
|
| Explanation: | The show ip bgp command shows the BGP attributes and their values. This will verify any configuration changes made to tweak the BGP configuration. |
|
| Question: | In the show ip bgp output what does a status code of d means?
A. The route is deleted.
B. The route is deleted from the BGP table.
C. The route is dampened.
D. The route is being distibuted amongst the iBGP peers.
|
| Answer: | C. The route is dampened.
|
| Explanation: | If a route in the BGP table has a status code of d it means that this entry has been dampened. |
|
| Question: | Which of the following BGP attributes are used in optimal path selection?
A. Originator ID
B. Origin
C. Atomic Aggregate
D. Next Hop
E. Aggregator
F. Local Preference
G. Community
|
| Answer: | B. Origin
D. Next Hop
F. Local Preference
|
| Explanation: | BGP uses the the following attributes in path selection:
- Origin
- AS_Path
- Next Hop
- Multiple Exit Discriminator
- Local Preference
- Weight |
|
| Question: | Which OSPF debug command can we use to view the DR selection?
A. debug ip ospf adjacencies
B. debug ip ospf events
C. debug ospf events
D. debug ip ospf summary
|
| Answer: | B. debug ip ospf events
|
| Explanation: | The debug ip ospf events command will display information on OSPF related events such as adjacencies, DR selection, flooding information, SPF calculation. |
|
| Question: | If we do not want to use an OSPF debug command but still want receive syslog messages when adjacencies are changed which command do we use?
A. log-adjacency
B. log-adjacency-all
C. log-adjacency-changes
D. log-adjacency-changes ospf
|
| Answer: | C. log-adjacency-changes
|
| Explanation: | The log-adjacency-changes router configuration command will send syslog messages when adjacencies are changed. This command requires less resources then the debug commands. |
|
| Question: | Which of the following statements are true?
A. 802.1Q encapsulates the whole frame between its header and trailer.
B. ISL adds a 4 byte-tag to the frame.
C. 802.1Q adds a 6 byte-tag to the frame.
D. ISL adds a 6 byte-tag to the frame.
E. ISL adds a new header to the frame.
F. 802.1Q adds a new header to the frame.
G. ISL encapsulates the whole frame between its header and trailer.
H. 802.1Q adds a 4 byte-tag to the frame.
|
| Answer: | G. ISL encapsulates the whole frame between its header and trailer.
H. 802.1Q adds a 4 byte-tag to the frame.
|
| Explanation: | ISL encapsulates the whole frame between its header and trailer while 802.1Q adds a 4 byte-tag to the frame. |
|
| Question: | How do we configure a switch port to be a 802.1Q trunk?
A. S1(config-if)#switchport trunk encapsulation dot1q S1(config-if)#switchport mode access
B. S1(config-if)#switchport trunk encapsulation dot1q S1(config-if)#switchport mode trunk
C. S1(config-if)#switchport trunk encapsulation 802.1Q S1(config-if)#switchport mode trunk
D. S1(config-if)#trunk encapsulation dot1q S1(config-if)#switchport mode trunk
|
| Answer: | B. S1(config-if)#switchport trunk encapsulation dot1q S1(config-if)#switchport mode trunk
|
| Explanation: | In order to configure a switchport as a trunk we set the encapsulation type with the switchport trunk encapsulation {isl | dot1q | negotiate} interface configuration command. Still in interface configuration mode we use the switchport mode trunk command to tell the swith that this port is a trunk. |
|
| Question: | How do we redistribute a supernet in BGP without using the aggregate-address command?
A. By creating a static route for the supernet to Null0 and redistribute this route into BGP.
B. This can not be done because BGP does not support VLSM.
C. By redistributing the supernet into a dynamic routing protocol.
D. By creating a static route for the supernet to the BGP speaking router at the egress point of the AS and redistriute this route into BGP.
|
| Answer: | A. By creating a static route for the supernet to Null0 and redistribute this route into BGP.
|
| Explanation: | Using a static route for the supernet pointing to Null0 and then redistributing this into BGP will let BGP advertise this route to its peers. If how ever this route dissappears from the IGP routing table it will still be advertised from BGP and traffic for will enter into the AS but without a destination and travel around the AS untill the TTL is expired and the packet is dropped. |
|
| Question: | We want to know when the last time SPF was executed on our IS-IS router. Which command do we use?
A. show clns spf-log
B. show clns spf
C. show log
D. show is-is spf-log
E. show is-is spf
|
| Answer: | D. show is-is spf-log
|
| Explanation: | The show is-is spf-log command will display the last 20 occurences that triggered a SPF calculation on the router. |
|
| Question: | How can we display Sequence Number Packets in IS-IS?
A. debug is-is events
B. show is-is packet
C. debug is-is statistics
D. debug is-is update-packets
|
| Answer: | D. debug is-is update-packets
|
| Explanation: | The debug is-is update-packets will display sequence number packets (CSNP and PSNP) and LSPs that are detected by the router. |
|
| Question: | We want to see the Hellos exchanged by our EIGRP router. How do we achieve this?
A. show ip eigrp
B. debug ip eigrp traffic
C. debug ip eigrp neighbors
D. debug ip eigrp
E. debug eigrp neighbors
|
| Answer: | E. debug eigrp neighbors
|
| Explanation: | The debug eigrp neighbors command will display Hello packets sent and received by the router and neighbors discovered via this process. |
|
| Question: | We want to control the BGP traffic by filtering out autonomous systems. How can do this?
A. Use of Autonomous System path prefix-lists
B. Use of Autonomous System path distribute-lists
C. Use of Extended access-lists
D. Use of Autonomous System path access-lists
|
| Answer: | D. Use of Autonomous System path access-lists
|
| Explanation: | We can use AS Path access-list to filter on Autonomous Systems. |
|
| Question: | What can we minimize the effect of flapping BGP routes?
A. Increase the time between Keepalive messages
B. Implement route dampening
C. Nothing
D. Implement prefix-lists
|
| Answer: | B. Implement route dampening
|
| Explanation: | When a route starts flapping this a damaging to the BGP table because of the extra network traffic and CPU resources used by the router. By implementing route dampening a flapping route will be considered an ill-behaved route and will get a penalty every time it flaps. If the penalties exceed a configured limit that route will be dampened. |
|
| Question: | Which command can we use to verify the BGP peer is using the correct table version?
A. show bgp ip_address
B. show ip bgp table ip_address
C. show bgp neighbors ip_address
D. show ip bgp neighbors ip_address
|
| Answer: | D. show ip bgp neighbors ip_address
|
| Explanation: | The show ip bgp neighbors ip_address will display that the neighbors has been updated with that version of the primary BGP routing table. |
|
| Question: | If our BGP network consists of 15 routers and we want to make this a fully meshed network how many sessions would there be?
A. 210
B. 110
C. 225
D. 105
E. 100
|
| Answer: | D. 105
|
| Explanation: | We use the following formula to calculate the amount of sessions in a fully meshed network:
n(n-1)/2 in this case 15(15-1)/2 = 105 sessions. |
|
| Question: | Which command will advertise routes into the BGP process?
A. network network
B. neighbor network mask network_mask
C. network network mask network_mask
D. network network network_mask
|
| Answer: | C. network network mask network_mask
|
| Explanation: | The network network mask network_mask router configuration command will identify which networks to be advertised by BGP. |
|
| Question: | When there is no sharing of information between routing processes we call this ______________ ?
A. Areas
B. Redistribution-less
C. Ships in the night
D. Autonomous systems
|
| Answer: | C. Ships in the night
|
| Explanation: | When there is no sharing of network information between the routing processes it is referred to as ships in the night routing. |
|
| Question: | Why would there be more then 1 routing protocol running in the same organization?
A. Faster convergence
B. Smaller networks with different protocols are more stable
C. Transition between routing protocols
D. Host based solutions that need a different protocol
|
| Answer: | C. Transition between routing protocols
D. Host based solutions that need a different protocol
|
| Explanation: | Following are some reasons why an organization might run more then 1 routing protocol:
- It is transitioning between routing protocols
- It used to be a collection of small networks and are merging to 1 large network
- Host based solutions might require a different protocol, e.g. Unix hosts needing RIP to find gateways
- The organization has acquired another organization and the networks merge
- Different network administrator implemented different routing protocols
|
|
| Question: | The default seed metric of IS-IS is?
A. 0
B. 20
C. 10
D. infinity
|
| Answer: | A. 0
|
| Explanation: | | Routing Protocol | Default Seed Metric | Action | | RIP | infinity (since IOS 12.1) | no routes entered in the routing table | | IGRP | infinity | no routes entered in the routing table | | EIGRP | infintiy | no routes entered in the routing table | | IS-IS | 0 | routes entered in the routing table | | OSPF | 20 (type2) but from BGP 1(type 2) | routes entered in the routing table | | BGP | MED is given the IGP metric | routes entered in the routing table | |
|
| Question: | When a route is redistributed into another routing protocol without metrics defined it is assigned?
A. The same metric as the receiving protocol
B. The metric assigned is the average of metrics used by the receiving routing protocol
C. The seed metric
D. The metric remains the same
|
| Answer: | C. The seed metric
|
| Explanation: | The seed metric is assigned to all routes received into another routing protocol through redistribution. |
|
| Question: | How can we change the administrative distance of a routing protocol?
A. R1(config-router)#administrative-distance value
B. R1(config-if)#distance value
C. R1(config-router)#distance value default
D. R1(config-router)#distance value
|
| Answer: | D. R1(config-router)#distance value
|
| Explanation: | To change the administrative distance of a routing protocol we use the distance value router configuration command. |
|
| Question: | Which of the following statements about redistribution are true?
A. When a route is redistributed it inherits the administrative distance of the new routing protocol.
B. When a route is redistributed it inherits the metrics of the new routing protocol.
C. When more then 1 routing protocol is running on the router the route with the best administrative distance will be placed in the routing table.
D. When a route is redistributed the new routing protocol considers this route as an internal route.
|
| Answer: | A. When a route is redistributed it inherits the administrative distance of the new routing protocol.
C. When more then 1 routing protocol is running on the router the route with the best administrative distance will be placed in the routing table.
|
| Explanation: | The following rules are important to consider when using redistribution:
- When a route is redistributed it inherits the administrative distance of the new routing protocol.
- When more then 1 routing protocol is running on the router the route with the best administrative distance will be placed in the routing table.
- When a route is redistributed the new routing protocol considers this route as an external route.
- In order for a route to be redistributed it must have an entry in the routing protocol from where it originates |
|
| Question: | Which of the following could be problems occuring when using route redistribution?
A. Faster convergence
B. Suboptimal routing
C. Optimal routing
D. Routing loops
E. Simple configuration
|
| Answer: | B. Suboptimal routing
D. Routing loops
|
| Explanation: | Some of the problems that can occur when using route redistribution:
- Suboptimal routing could occur when the wrong or less efficient routing decision is made
- Routing loops could occur
- Convergence time of the network increases because of the different technologies used
- The decision-making process and the information sent within the protocols could incompatible and could lead to errors and complex configuration |
|
| Question: | In RIP, an interface that listens to updates but doesnt send any is a __________ interface.
A. passive
B. quiet
C. silent
D. dampened
|
| Answer: | A. passive
|
| Explanation: | A passive interface is an interface that doesnt participate in the routing process. In RIP and IGRP it will listen to updates but wont send any, in EIGRP and OSPF it will not send or listen to Hellos so no adjacencies will be formed. |
|
| Question: | When redistributing in EIGRP and using the default-metric command, in what order are the composite metrics applied?
A. First,Second,Third,Fourth,Fifth
B. Bandwidth,Delay,Reliability,Loading,MTU
|
| Answer: | B. Bandwidth,Delay,Reliability,Loading,MTU
|
| Explanation: | When redistributing in EIGRP, composite metric is assigned with the default-metric bandwidth delay reliability loading mtu command. |
|
| Question: | How do we change the administrative distance of EIGRP?
A. R1(config)#router eigrp 10 R1(config-router)#distance eigrp 80 150
B. R1(config)#router eigrp 10 R1(config-router)#distance eigrp 80 150 default
C. R1(config)#router eigrp 10 R1(config-router)#eigrp-distance 80
D. R1(config)#router eigrp 10 R1(config-router)#distance 80 150
|
| Answer: | A. R1(config)#router eigrp 10 R1(config-router)#distance eigrp 80 150
|
| Explanation: | In order to change the administrative distance of EIGRP we use the distance eigrp internal-distance external-distance in router configuration mode. |
|
| Question: | When using the redistribute command we can specify the metric-type. For which routing protocol is this necessary?
A. OSPF
B. BGP
C. EIGRP
D. RIP
E. IS-IS
|
| Answer: | A. OSPF
|
| Explanation: | The metric-type keyword of the redistribute command is used by OSPF. It is used to specify the external link type, type 1 or type 2, associated with the default route advertised into OSPF. |
|
| Question: | How do we configure a candidate default path?
A. ip default-network network
B. ip default network
C. ip network network
D. ip default-network network network_mask
|
| Answer: | A. ip default-network network
|
| Explanation: | When a router is not directly connected to the default network but does have a route to it, it is considered a candidate default path. We can configure multiple candidate paths with the ip default-network network global configuration command. |
|
| Question: | What can you use to filter routing updates out of the routing process?
A. Passive-interface
B. Static routes
C. Distribute lists
D. Default routes
|
| Answer: | C. Distribute lists
|
| Explanation: | Distribute lists are access-lists applied to the routing process to determine which networks are entered in the routing table or are send in updates. |
|
| Question: | Of the routes being redistributed in our network we do not want the 10.1.0.0/16 network for security reasons. How do we configure the router to achieve this?
A. R1(config)#router ospf 10 R1(config-router)#redistribute eigrp metric-type 2 R1(config-router)#distribute-list 10 in R1(config)#access-list 10 deny 10.1.0.0
B. R1(config)#router ospf 10 R1(config-router)#redistribute eigrp metric-type 2 R1(config-router)#distribute-list 10 in R1(config)#access-list 10 permit 10.1.0.0
C. R1(config)#router ospf 10 R1(config-router)#redistribute eigrp metric-type 2 R1(config-router)#distribute-list 10 in
D. R1(config)#router ospf 10 R1(config-router)#redistribute eigrp metric-type 2 R1(config-router)#distribute-list 10 out R1(config)#access-list 10 deny 10.1.0.0
|
| Answer: | A. R1(config)#router ospf 10 R1(config-router)#redistribute eigrp metric-type 2 R1(config-router)#distribute-list 10 in R1(config)#access-list 10 deny 10.1.0.0
|
| Explanation: | We use a distribute-list to filter out the network. The distribute-list will refer to an access list that permits or denies a network to be entered in the routing table |
|
| Question: | Which of the following are part of the DSP in IS-IS?
A. High Order DSP
B. IDI
C. System ID
D. Area ID
E. NSEL
F. AFI
|
| Answer: | A. High Order DSP
C. System ID
E. NSEL
|
| Explanation: | The DSP or Domain Specific Part consists of:
- High Order DSP
- System ID
- NSEL
|
|
| Question: | Which command do we use to view the parameters of the routing procotols active on the router?
A. show ip protocols
B. show protocols
C. show route protocols
D. show ip route protocols
|
| Answer: | A. show ip protocols
|
| Explanation: | The show ip protocols will display the parameters and current state of the active routing protocol process(es). |
|
| Question: | How do we enable WFQ on an interface with a speed higher then 2Mbps?
A. Fair-queue
B. Weighted-fair-queue
C. Fair-queue enable
D. Weighted-fair-queue enable
|
| Answer: | A. Fair-queue
|
| Explanation: | To enable weighted fair queueing (WFQ) for an interface, use the fair-queue interface configuration command. WFQ is enabled by default on interfaces that have a bandwidth of 2.048Mbps or less. |
|
| Question: | Which utility do we use to identify where a problem is in the network?
A. Trace
B. Ping
C. Telnet
D. Show ip route
|
| Answer: | A. Trace
|
| Explanation: | The trace utility will identify where there is a problem in the network. Where the trace utility fails indicates a good starting point to troubleshoot the problem. |
|
| Question: | When would you use route maps?
A. To control redistribution
B. To control bandwidth
C. To define policies in policy-based routing
D. To define more granular access lists
E. To implement BGP
|
| Answer: | A. To control redistribution
C. To define policies in policy-based routing
|
| Explanation: | Route maps can be used for the following:
- To control redistribution
- To control and modify routing information
- To define policies in policy-based routing
- To add granularity in the configuration of NAT
- To implement BGP policy-based routing |
|
| Question: | When will a set command be applied in the route map?
A. When the packet match the criteria and the criteria is set to permit.
B. When the packet match the criteria and the criteria is set to deny.
C. When the packet doesnt match the criteria but the criteria is set to deny.
D. When there is no match criteria specified but the route map is a deny.
|
| Answer: | A. When the packet match the criteria and the criteria is set to permit.
|
| Explanation: | The set command will only be applied if the statement is marked as permit and the packet meets the criteria. |
|
| Question: | Which of the following statements are true about route maps?
A. When a match is made the route map stops, just like access lists.
B. Only extended access lists can be used with route maps.
C. A route map has a list of criteria defined with the match statement.
D. A route map checks the criteria from highest sequence number to lowest.
E. At the end of a route map there is an implicit permit and not an implicit deny like access lists.
|
| Answer: | A. When a match is made the route map stops, just like access lists.
C. A route map has a list of criteria defined with the match statement.
|
| Explanation: | Route maps can use standard and extended IP access list and just like access lists they have an implicit deny at the end.
Again, like access list, route maps are checked sequencially starting at the lowest number. |
|
| Question: | What are some disadvantages of policy-based routing?
A. QoS can not be implemented
B. More powerfull routers mean a bigger financial cost.
C. Load balancing can not be implemented
D. Extra configuration is needed.
E. Additional CPU and memory resources needed.
|
| Answer: | D. Extra configuration is needed.
E. Additional CPU and memory resources needed.
|
| Explanation: | Some disadvantages of policy-based routing are:
- A backup path should be in place in case the defined next-hop router goes down
- Additional CPU is required to examine every source address to effect the defined policy
- Extra configuration is required
- Possibility exists that other traffic will be affected |
|
| Question: | How do we "enable" a route map for incoming traffic?
A. R1(config)#ip policy route-map route_map_name
B. R1(config-router)#ip policy route-map route_map_name
C. R1(config-if)#ip route-map route_map_name
D. R1(config-if)#ip policy route-map route_map_name
|
| Answer: | D. R1(config-if)#ip policy route-map route_map_name
|
| Explanation: | When a route map has been configured we use the ip policy route-map route_map_name interface configuration command for to enable it for incoming traffic. |
|
| Question: | How do we enable fast-switched policy-based routing?
A. R1(config-if)#ip route-cache policy
B. R1(config)#ip route-cache policy
C. R1(config-router)#route-cache policy
D. R1(config-if)#ip policy route-map route_map_name fast-switched
|
| Answer: | A. R1(config-if)#ip route-cache policy
|
| Explanation: | To enable fast-switched policy-based routing we use the ip route-cache policy interface configuration command. |
|
| Question: | How do we change the next hop for routes coming from 192.168.1.1?
A. route-map Free-Tests deny 10 match ip address 10 set ip next-hop next_hop
access-list 10 permit 192.168.1.1
B. route-map Free-Tests permit 10 match ip address 10 set ip next-hop next_hop
access-list 10 permit 192.168.1.1
C. route-map Free-Tests permit 10 match ip address 10 set ip next-hop next_hop
D. route-map Free-Tests permit 10 match ip address 10 set ip next-hop next_hop
access-list 1 permit 192.168.1.1
|
| Answer: | B. route-map Free-Tests permit 10 match ip address 10 set ip next-hop next_hop
access-list 10 permit 192.168.1.1
|
| Explanation: | We use the set ip next hop command to alter the next hop for routes coming from 192.168.1.1, there must be an entry for the destination network of the packet in the routing table. |
|
| Question: | When there is no match in policy-based routing what happens to the packet?
A. It is discarded and the source receives an ICMP destination unreachable message.
B. It is routed to the Null0 interface and the source does not receive an ICMP destination unreachable message.
C. It is routed to the Null0 interface and the source receives an ICMP destination unreachable message.
D. It is send to the normal routing process to be routed to the destination.
|
| Answer: | D. It is send to the normal routing process to be routed to the destination.
|
| Explanation: | When the packet does not match any of the criteria of the route map it is send to the normal routing process to be routed by destination. |
|
| Question: | What is the difference between set ip default next-hop and set ip next-hop?
A. IP default next-hop is used when there is no entry in the routing table for the destination network and ip next-hop there must be an entry for the destination network in the routing table.
B. IP next-hop is used when there is no entry in the routing table for the destination network and ip default next-hop there must be an entry for the destination network in the routing table.
C. The ip default next-hop is used to set the default route and ip next-hop is just used to alter the path to the destination.
D. There is no difference between the two set commands.
|
| Answer: | A. IP default next-hop is used when there is no entry in the routing table for the destination network and ip next-hop there must be an entry for the destination network in the routing table.
|
| Explanation: | Set ip default next-hop>/b> is used when the routing table has no entry for the destination network of the packet. The set ip next-hop is used when there is an entry for the destination network in the routing table. Both must have the address of the adjacent router. |
|
| Question: | How can we control redistribution by only allowing routes that have a certain metric?
A. match route-type
B. match ip metric
C. match ip route-source
D. match metric
E. match tag
|
| Answer: | D. match metric
|
| Explanation: | The match metric will only redistribute routes with the metric specified. |
|
| Question: | How can we display a list of route maps used for policy-based routing on the routers interface?
A. show ip interface policy
B. show ip interface route-map
C. show route-map
D. show ip policy
|
| Answer: | D. show ip policy
|
| Explanation: | The show ip policy displays the route maps used for policy-based routing on the routers interface. |
|
| Question: | How do we apply policy-based routing to packets generated by the router?
A. R1(config)#ip policy route-map route_map_name
B. R1(config-router)#ip local policy route-map route_map_name
C. R1(config-if)#ip policy route-map route_map_name local
D. R1(config)#ip local policy route-map route_map_name
E. R1(config-if)#ip local policy route-map route_map_name
|
| Answer: | D. R1(config)#ip local policy route-map route_map_name
|
| Explanation: | To apply policy-based routing on packets generated by the router we use the ip local policy route-map route_map_name global configuration command. |
|
| Question: | How can see the dynamic changes being made to the EIGRP routing table?
A. debug ip eigrp
B. debug eigrp route
C. debug ip eigrp packet
D. debug ip eigrp neighbors
|
| Answer: | A. debug ip eigrp
|
| Explanation: | When the debug ip eigrp command is issued it will default to debug ip eigrp route that will show the dynamic changes made to the routing table. |
|
| Question: | The administrative distance of IS-IS is?
A. 120
B. 90
C. 100
D. 160
E. 115
F. 110
|
| Answer: | E. 115
|
| Explanation: | | Source | Administrative Distance | | Connected Interface | 0 | | Static Route | 1 | | EIGRP Summary Route | 5 | | External BGP | 20 | | Internal EIGRP | 90 | | IGRP | 100 | | OSPF | 110 | | IS-IS | 115 | | RIP | 120 | | EGP | 140 | | On Demand Routing (ODR) | 160 | | External EIGRP | 170 | | Internal BGP | 200 | |
|
| Question: | When an IS-IS LSP arrives on a router with the OL bit set what is the significance of this?
A. The sending router is a L1/L2 router.
B. The sending router has run out of CPU cycles to calculate the SPF algorithm.
C. The sending router has run out of memory for the link-state database.
D. The sending router had detected congestion on the link.
|
| Answer: | C. The sending router has run out of memory for the link-state database.
|
| Explanation: | When a LSP has the OL (overload) bit set it means that the generating router has run out of memory for the link-state database. |
|
| Question: | OSPF sends out the topology table every ___________ ?
A. 30 seconds
B. 90 minutes
C. 60 minutes
D. 90 seconds
E. 30 minutes
F. 60 seconds
|
| Answer: | E. 30 minutes
|
| Explanation: | OSPF exchanges the full topology table at least every 30 minutes between adjacent routers. |
|
| Question: | Which of the following statements are true when you configure OSPF point-to-multipoint?
A. Each spoke in the network has its own subnet.
B. There is a DR/BDR election.
C. The network uses 1 subnet.
D. There is no DR/BDR election.
E. The network has to be fully meshed.
|
| Answer: | C. The network uses 1 subnet.
D. There is no DR/BDR election.
|
| Explanation: | When using point-to-mulitpoint OSPF configuration the network is in one subnet and there is no DR/BDR election. |
|
| Question: | Integrated IS-IS supports which protocols?
A. IP
B. CLNP
C. DecNet
D. IPX
E. AppleTalk
|
| Answer: | A. IP
B. CLNP
|
| Explanation: | Integrated IS-IS supports IP and CLNP. |
|
| Question: | What is the range of multicast addresses in IPv6?
A. FF00::/16 to FFAA::16
B. FF00::/8 to FF99::/8
C. FF00::/8 to FFFF::/8
D. FF00::/16 to FFFF::/16
E. FF00::/8 to FFAA::/8
|
| Answer: | C. FF00::/8 to FFFF::/8
|
| Explanation: | The multicast address range in IPv6 is FF00::/8 to FFFF::/8 because all IPv6 multicast addresses have the first 8 bits set to 1, 1111 1111 or FF. |
|
| Question: | Which command will display the DoNotAge external LSA?
A. Show ip ospf interface
B. Show ip ospf database
C. Show ospf database
D. Show ip ospf neighbor
E. Show ip ospf process_id
|
| Answer: | E. Show ip ospf process_id
|
| Explanation: | The show ip ospf process_id command will display the DoNotAge External LSA used with OSPF demand circuits, like ISDN. |
|
| Question: | OSPF supports which forms of authentication?
A. Radius
B. MD5
C. Kerberos
D. Simple passwords
E. NTLM
|
| Answer: | B. MD5
D. Simple passwords
|
| Explanation: | OSPF supports simple passwords and MD5 authentication to authenticate packets send between neighbors. |
|
| Question: | How do we prevent OSPF Hellos being sent out of the ethernet interface of R1?
A. R1(config)#router ospf 10 R1(config-router)#passive-interface ethernet 0
B. R1(config-if)#passive-interface ospf
C. R1(config)#passive-interface ethernet 0
D. R1(config)#router ospf 10 R1(config-router)#passive interface ethernet 0
|
| Answer: | A. R1(config)#router ospf 10 R1(config-router)#passive-interface ethernet 0
|
| Explanation: | To surpress OSPF or EIGRP Hello packets or RIP updates we can use the passive-interface interface router configuration command. |
|
| Question: | How do we change the percentage of bandwidth used by EIGRP for its traffic?
A. R1(config)#interface ethernet 0 R1(config-if)#ip bandwidth-percent eigrp_as percent
B. R1(config)#interface ethernet 0 R1(config-if)#ip bandwidth-percent eigrp eigrp_as percent
C. R1(config)#router eigrp 10 R1(config-router)#ip bandwidth-percent percent interface
D. R1(config)#ip bandwidth-percent eigrp eigrp_as percent
|
| Answer: | B. R1(config)#interface ethernet 0 R1(config-if)#ip bandwidth-percent eigrp eigrp_as percent
|
| Explanation: | To change the percentage of bandwidth used by EIGRP for its traffic we use the ip bandwidth-percent eigrp eigrp_as percent interface configuration command. |
|
| Question: | How can we view the content of each LSP sent by IS-IS?
A. show isis database lspid
B. show isis database
C. show isis database detail
D. show isis database summary
|
| Answer: | C. show isis database detail
|
| Explanation: | The show isis area database command with the keyword detail added will show the content of each LSP. |
|
| Question: | Which command will tell us what type of OSPF router the router is we are connected to?
A. show ip ospf neighbor
B. show ip ospf database
C. show ip ospf interface
D. show ip ospf process_id
|
| Answer: | D. show ip ospf process_id
|
| Explanation: | The show ip ospf process_id will display the specific type of OSPF router, e.g. It is an internal router. |
|
| Question: | When a BGP AS is broken up into smaller sub-ASs we call those?
A. Confederations
B. Peer Group
C. Domain
D. Route Reflectors
E. Private AS
|
| Answer: | A. Confederations
|
| Explanation: | When an AS is divided in smaller sub-ASs we call it a confederation. Inside each confederation the rules of iBGP apply, e.g. they must be fully meshed. |
|
| Question: | On which layer of the OSI model do we find a TCP Segment?
A. Network
B. Presentation
C. Data Link
D. Physical
E. Transport
F. Session
|
| Answer: | E. Transport
|
| Explanation: | TCP Segments are found on the Transport layer of the OSI Model. |
|
| Question: | In MLS, what is used for the traditional Layer 3 routing function?
A. BGP
B. MPLS
C. Cisco Express Forwarding
D. Store-and-Forward
E. Cut-Through
|
| Answer: | C. Cisco Express Forwarding
|
| Explanation: | In MLS, Multilayer Switching, the traditional Layer 3 routing function is provided by Cisco Express Forwarding (CEF). A database of routes to every destination network is maintained and distributed to switching ASICs for very high forwarding performance. |
|
| Question: | On a broadcast multiaccess OSPF network Hellos are send every _______ ?
A. 10 seconds
B. 40 seconds
C. 30 minutes
D. 60 seconds
E. 90 seconds
|
| Answer: | A. 10 seconds
|
| Explanation: | Hellos are send periodically every 10 seconds (default) on a broadcast multiaccess media. |
|
| Question: | An IPv6 address that is within the same site but might be on a different network is a ____________ address?
A. Site local
B. Link local
C. Network local
D. Area local
|
| Answer: | A. Site local
|
| Explanation: | A site local is unicast address that is within the same site but it could be on a different network. |
|
| Question: | Where in the Cisco hierarchical design would you find access lists?
A. Distribution layer
B. Access layer
C. Core layer
D. Network layer
E. Transport layer
|
| Answer: | A. Distribution layer
|
| Explanation: | The distribution layer is responsible for determining access across the backbone by filtering out unnecessary resource updates and selectively granting access to users and departments via access lists. |
|
| Question: | Which of the following routing protocols do support VLSM?
A. BGP
B. IGRP
C. EIGRP
D. RIPv1
E. IS-IS
F. OSPF
G. RIPv2
H. EGP
|
| Answer: | A. BGP
C. EIGRP
E. IS-IS
F. OSPF
G. RIPv2
|
| Explanation: | RIPv2, EIGRP, OSPF, IS-IS and BGP do support VLSM. |
|
| Question: | Given the network 192.168.1.0/24 what will be subnetmask if we only want 20 hosts on each subnet?
A. /30
B. /29
C. /28
D. /27
|
| Answer: | D. /27
|
| Explanation: | In order for us to get 20 hosts on each subnet we need 5 bits of the last octet this will give us 2^5 - 2 = 30 hosts on each subnet. We still have 3 bits left for available subnets. So the subnetmask is 255.255.255.224 or /27. |
|
| Question: | EIGRP uses which multicast address for updates?
A. 224.0.0.10
B. 224.0.0.5
C. 224.0.0.6
D. 224.0.0.9
E. 224.0.0.1
|
| Answer: | A. 224.0.0.10
|
| Explanation: | EIGRP uses 224.0.0.10 for sending out routing updates. |
|
| Question: | In IS-IS what best describes a pseudonode?
A. A router that is only connected to the backbone and provide transit traffic between areas.
B. A group of routers running the IS-IS protocol.
C. A service at the network layer to which the packet is to be directed.
D. The LAN identifier for a broadcast subnetwork.
|
| Answer: | D. The LAN identifier for a broadcast subnetwork.
|
| Explanation: | A pseudonode is the LAN identifier for a broadcast subnetwork. It makes the broadcast domain appear as a virtual router and the routers appear as connected interfaces. |
|
| Question: | When a router has multiple routes to a network what will be used to route a packet to that network?
A. The route that was learned first.
B. The route that uses the fastest interface.
C. The route that matches the shortest prefix length.
D. The route that matches the longest prefix length.
E. The route that was learned last.
|
| Answer: | D. The route that matches the longest prefix length.
|
| Explanation: | The forwarding process will use the route where the most number of subnet bits match that of the destination network. This is known as match to the longest prefix length. |
|
| Question: | Which of the following are part of the switching function in a router?
A. Check if there are multiple equal-cost paths.
B. Check for the best path to the destination.
C. Check if the frame passes the crc.
D. Check if there is a layer 2 address.
|
| Answer: | C. Check if the frame passes the crc.
D. Check if there is a layer 2 address.
|
| Explanation: | The switching function on a router performs the following steps:
- checks the incoming frame for validity
- checks if it contains a layer 2 address to the router
- checks the size of the frame, not too big or too small
- checks if it passes the cyclic redundancy check
- strips the layer 2 header and trailer and checks the destination address against its cache
- creates the new frame header and trailer and places the frame in the outbound interface queue |
|
| Question: | Which of the following are routed procotols?
A. AppleTalk
B. IP
C. IPX
D. OSPF
E. NetBeui
F. SPX
G. TCP
H. BGP
I. IS-IS
|
| Answer: | A. AppleTalk
B. IP
C. IPX
|
| Explanation: | A routed protocol is the layer 3 protocol used to transfer data from one end device to another across the network. AppleTalk, IPX, IP, Vines, DECnet IV are examples of routed protocols. |
|
| Question: | What is described by the following:
A value assigned to each path based on the criteria specified in the routing protocol.
A. Subnetmask
B. Prefix length
C. Path cost
D. Administrative Distance
E. Bandwidth
F. Metric
|
| Answer: | F. Metric
|
| Explanation: | The metric is a value assigned to each path based on the criteria specified in the routing protocol. |
|
| Question: | Looking at the routing table we see routes marked with i, via which protocol are these routes learned?
A. IS-IS
B. BGP
C. IGRP
D. EIGRP
E. OSPF
|
| Answer: | A. IS-IS
|
| Explanation: | Routes that are marked with an i in the routing table are routes learned via IS-IS.
R1# show ip route
Codes:
I - IGRP derived, R - RIP derived, O - OSPF derived,
C - connected, S - static, E - EGP derived, B - BGP derived,
* - candidate default route, IA - OSPF inter area route,
i - IS-IS derived, ia - IS-IS, U - per-user static route,
o - on-demand routing, M - mobile, P - periodic downloaded static route,
D - EIGRP, EX - EIGRP external, E1 - OSPF external type 1 route,
E2 - OSPF external type 2 route, N1 - OSPF NSSA external type 1 route,
N2 - OSPF NSSA external type 2 route |
|
| Question: | The maximum amount of equal-costs paths on a Cisco router is by default?
A. 2
B. 8
C. 10
D. 4
E. 6
|
| Answer: | D. 4
|
| Explanation: | On a Cisco router, if multiple equal-cost paths exist in IP up to 6 paths can be used to load balance traffic across the network in a round-robin manner. The default is 4 paths. |
|
| Question: | We want to enter a static route in the routing table that will stay there even if the interface shuts down. How do we achieve this?
A. ip route 192.168.1.0 255.255.255.0 172.16.1.1
B. ip route 192.168.1.0 255.255.255.0 serial0/1
C. ip route 192.168.1.0 255.255.255.0 172.16.1.1 persistent
D. ip route 192.168.1.0 255.255.255.0 172.16.1.1 permanent
|
| Answer: | D. ip route 192.168.1.0 255.255.255.0 172.16.1.1 permanent
|
| Explanation: | Using the permanent keyword with the ip route command ensures that the route will not be removed from the routing table even if the interface shuts down. |
|
| Question: | Which of the following are valid statements for implementing static routes?
A. Using static routes makes scalability easier.
B. The network is a stub network.
C. Static routes are more reliable since there is no convergence in case of a failure.
D. The network administrator needs control over the link.
E. Static routes are easier to confgure no matter what the size of the network is.
|
| Answer: | B. The network is a stub network.
D. The network administrator needs control over the link.
|
| Explanation: | Some reasons for implementing static routes are:
- low bandwidth link, e.g. dial-up links
- you need control over the link
- the link is a backup to the dynamically learned route
- there is only 1 path to the remote network, a stub network
- router has limited resources and can not run a routing protocol
|
|
| Question: | ODR uses which protocol to send prefixes from the remote router to the core router?
A. IGRP
B. SNMP
C. Static routing
D. EIGRP
E. CDP
|
| Answer: | E. CDP
|
| Explanation: | ODR or On Demand Routing uses Cisco Discovery Protocol (CDP) to send the prefixes of attached networks from the spoke or remote router to the hub or core router. |
|
| Question: | By default ODR sends updates every 60 seconds we want this to decrease to 30 seconds. How do we achieve this?
A. R1(config-if)#ODR timer 30
B. R1(config-if)#timer 30
C. R1(config-if)#cdp timer 30
D. R1(config)#ODR timer 30
|
| Answer: | C. R1(config-if)#cdp timer 30
|
| Explanation: | Because ODR, On Demand Routing, uses CDP (Cisco Discovery Protocol) we can change the update interval by changing the CDP timer to send out updates more or less frequently then every 60 seconds (default). |
|
| Question: | Networks logically grouped together under one administrative control is called a(n) _________ ?
A. Backbone
B. Autonomous system
C. Area
D. Domain
E. Workgroup
F. Hierarchy
|
| Answer: | B. Autonomous system
|
| Explanation: | An autonomous system is a logical grouping of networks under one administrative control. |
|
| Question: | We want to create 15 subnets of the 172.16.0.0/16 address. How many hosts are available on each subnet?
A. 2044
B. 2046
C. 2048
D. 2050
|
| Answer: | B. 2046
|
| Explanation: | To give us 15 subnets we use 5 bits of the host portion giving us 30 available subnets [2^5 - 2 = 30]. This leaves us 11 bits available for hosts, 2^11 - 2 = 2046 hosts on each subnet. |
|
| Question: | What are some advantages of using prefix routing?
A. allows for complex routing protocols to be used on private networks.
B. eliminates the need for an exterior routing protocol.
C. eliminates the need for route summarization
D. reduction in the size of the routing table.
E. greater flexibility in network addressing.
|
| Answer: | D. reduction in the size of the routing table.
E. greater flexibility in network addressing.
|
| Explanation: | Following are some benefits of Prefix Routing/CIDR:
- reduces the routing table in size
- allows for more flexibility in network addressing
- less overhead in network traffic, CPU and Memory |
|
| Question: | Which of the following routing protocols do not support VLSM?
A. EGP
B. BGP-4
C. IGRP
D. RIPv2
E. OSPF
F. RIPv1
G. IS-IS
|
| Answer: | A. EGP
C. IGRP
F. RIPv1
|
| Explanation: | The following routing protocols support VLSM:
- RIPv2
- OSPF
- IS-IS
- EIGRP
- BGP-4
|
|
| Question: | Ciscos hierarchical design consists of which layers?
A. Access
B. Internetwork
C. Core
D. Backbone
E. Distribution
F. Network
|
| Answer: | A. Access
C. Core
E. Distribution
|
| Explanation: | The Cisco hierarchical design model has the following layers:
- The core layer
- The distribution layer
- The access layer
|
|
| Question: | Which of the following elements would find on the core layer of Ciscos hierarchical design?
A. NAT
B. Complex routing decisions
C. Access-lists
D. QoS
E. Redundancy
|
| Answer: | D. QoS
E. Redundancy
|
| Explanation: | The core layers main function is to connect the entire enterprise by interconnecting the distributions layer devices. To achieve maximum availability we need a highly redundant layer. Any services, e.g. filtering (Access lists), NAT etc. should be removed from this layer since they create a latency in the forwarding process. To ensure higher priority to certain traffic types QoS can be implemented at this layer. |
|
| Question: | Distribution lists can be used to achieve which of the following?
A. Prevent routing loops when redistributing between multiple routing protocols.
B. To change the metrics of routes redistributed in another routing protocol.
C. Hide networks, e.g. labs, secure networks, to be advertised to the whole network.
D. To tag routes being redistributed from one routing protocol in another.
E. To change the priority of a packet when it travels across the network.
|
| Answer: | A. Prevent routing loops when redistributing between multiple routing protocols.
C. Hide networks, e.g. labs, secure networks, to be advertised to the whole network.
|
| Explanation: | Distribute lists are access lists applied to the routing process to determine which networks will be accepted in the routing table or sent in updates. The can also function to control security, overhead and management reasons. |
|
| Question: | Which form of queuing has a threshold stating the number of bytes or packets that might be sent before servicing the next queue?
A. Priority queuing
B. Cisco express forwarding
C. Class-Based weighted fair queuing
D. Weighted fair queuing
E. Custom queuing
F. Low-Latency queuing
|
| Answer: | E. Custom queuing
|
| Explanation: | In custom queuing the interface buffer is divided into 16 queues. Each queue has a threshold stating the number of bytes or packets that might be sent before servicing the next queue. |
|
| Question: | Besides access lists we can use an another method to reduce network traffic that is not so demanding on resources as access lists. Which method is that?
A. distribution list
B. custom queueing
C. null interface
D. offset list
|
| Answer: | C. null interface
|
| Explanation: | A null interface is virtual or logical interface that exists only in the operating system of the router, any traffic send to it disappears because the interface has no physical layer. By disabling ICMP Unreachable messages sent in response to packets send to the null interface the packets are silently dropped, i.e. no error message is sent to the transmitting device. |
|
| Question: | Which are some features of IPv6?
A. Security
B. No need for multicast addresses
C. Part of the IPv6 address is the NICs MAC address
D. Autoconfiguration
E. Complex header
|
| Answer: | A. Security
D. Autoconfiguration
|
| Explanation: | IPv6 has the following, and more, benefits and features:
- larger address space
- autoconfiguration
- renumbering
- security
- mobility
- simple and efficient header
- ... |
|
| Question: | In NAT terminology what is described by the following: "These addresses allow hosts in the organization to communicate"
A. Inside global
B. Outside local
C. Outside global
D. Inside local
|
| Answer: | D. Inside local
|
| Explanation: | Inside local addresses allow for each end device in the organization to communicate. These addresses are unique within the enterprise but they are probably not globally unique. They are the inside addresses as seen locally within the enterprise. |
|
| Question: | What does ::1 represent in IPv6?
A. Link local
B. Aggregate global unicast
C. Site local
D. Unspecified and Loopback
|
| Answer: | D. Unspecified and Loopback
|
| Explanation: | The unspecified and loopback IPv6 unicast address is represented 0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0000.0001 or
0.0.0.0.0.0.0.0.0.0.0.1 or
::1
It is often uses to download software or requesting an address. The loopback address is used to test the interface in basic troubleshooting. |
|
| Question: | The first 48 bits of an IPv6 address are used for?
A. To enter the MAC Address of the host.
B. To create an easy transistion from IPv4
C. To create the aggregate global unicast.
D. To create the multicast range.
|
| Answer: | C. To create the aggregate global unicast.
|
| Explanation: | The first 48 bits of an IPv6 address is the header used by the IANA for external routing within the Internet to create the aggregate global unicast. If this 48-bit prefix is not used the addressing scheme is similar to IPv4 private addressing. |
|
| Question: | Which of the following routing protocols support IPV6 on a Cisco router?
A. RIPv2
B. EIGRP
C. OSPF
D. IS-IS
E. RIPng
F. BGP-4
G. RIPv1
H. IGRP
|
| Answer: | C. OSPF
D. IS-IS
E. RIPng
F. BGP-4
|
| Explanation: | From Ciscos IOS 12.2T and later release the following routing protocols support IPv6:
- RIPng
- OSPF
- IS-IS
- BGP-4
|
|
| Question: | Which of the following techniques do distance vector protocols use to avoid routing loops?
A. flooding
B. counting to infinity
C. hop count
D. split horizon
E. holddown
|
| Answer: | D. split horizon
E. holddown
|
| Explanation: | Distance vectors use the following techniques to avoid routing loops:
- Split horizon
- Poison reverse
- Holddown
- Triggered updates
- Aging of routes from the routing table
Counting to infinity is a condition that occurs when a route disappears from the network and is found in distance vector protocols but strictly speaking this is not a technique. |
|
| Question: | Which routing loop avoidance technique is described? "The routing process will not advertise a route out of the interface through which that route was learned"
A. Poison reverse
B. Triggered update
C. Split horizon
D. Split horizon with poison reverse
|
| Answer: | C. Split horizon
|
| Explanation: | The split horizon rule state that the routing process will not advertise networks out of the interface through which those networks were learned. With poison reverse the routing process will advertise those networks but the metric will be set to infinite. |
|
| Question: | If switchport mode dynamic auto is configured the port will become a trunk when _______.
A. The other end is configured as trunk or dynamic desirable.
B. When the other end is configured as nonegotiate.
C. The other end is configured as dynamic auto.
D. Only when the other end is configured as trunk.
|
| Answer: | A. The other end is configured as trunk or dynamic desirable.
|
| Explanation: | When switchport mode dynamic auto is configured the port will become a trunk when the far-end switchport is set to trunk or dynamic desirable. |
|
| Question: | Which control protocol PDUs are sent over VLAN 1 on a trunk?
A. CDP
B. TPID
C. STP
D. DSCP
E. VTP
F. GLBP
G. SSP
H. SLB
|
| Answer: | A. CDP
C. STP
E. VTP
|
| Explanation: | STP, VTP and CDP are also known as Layer 2 Control Protocol Data Units and are sent over VLAN 1 on a trunk. |
|
| Question: | Which 2 requirements have to be fulfilled when using EoMPLS?
A. EoMPLS has to be configured on all MPLS routers.
B. EoMPLS has to be configured only on the interior label switch routers.
C. The service provider must have VPNs in the MPLS core network.
D. The service provider must have a MPLS core network.
E. EoMPLS has to be configured only on the edge routers.
|
| Answer: | D. The service provider must have a MPLS core network.
E. EoMPLS has to be configured only on the edge routers.
|
| Explanation: | An EoMPLS tunnel requires 2 things to be fulfilled:
- The service provider must have a MPLS core network
- EoMPLS must be configured only on the edge routers that interface with the customer networks |
|
| Question: | Which of the following parameters have to be negotiated before a trunk operates correctly?
A. trunk speed
B. DTP timers
C. STP timers
D. trunking mode
E. trunk encapsulation
|
| Answer: | D. trunking mode
E. trunk encapsulation
|
| Explanation: | For a trunk to operate correctly the following parameters have to be agreed on:
- trunking mode (trunk, negotiated, nonnegotiate) - encapsulation (ISL, 802.1Q, DTP negotiated) - native VLAN (802.1Q only) - allowed VLANs |
|
| Question: | Which command do we use to view the allowed VLANs on a trunk?
A. show interface trunk
B. show trunk vlan
C. show trunk interface type mod/num trunk
D. show interface type mod/num trunk
E. show trunk
|
| Answer: | D. show interface type mod/num trunk
|
| Explanation: | The show interface type mod/num trunk command will display information about allowed VLANs, encapsulation, native VLAN,... |
|
| Question: | Which of the following are NOT VTP modes?
A. Master
B. Client
C. Transitional
D. Transparent
E. Native
F. Slave
G. Server
|
| Answer: | A. Master
C. Transitional
E. Native
F. Slave
|
| Explanation: | VTP has 3 modes:
- Server
- Client
- Transparent |
|
| Question: | In which VTP mode can you create locally significant VLANs?
A. Client
B. Native
C. Transparent
D. Server
|
| Answer: | C. Transparent
|
| Explanation: | In transparent mode you can create VLANs on the switch but the switch does not synchronize its database with received VTP advertisments nor will it advertise its own VLAN configuration. |
|
| Question: | How can we reset the VTP revision number back to zero?
A. By using the clear vtp counters command.
B. Change the switch to client mode then change it back to server mode.
C. By using the clear vtp command.
D. Change the switch to transparent mode then change it back to server mode.
E. Change the switchs VTP domain name and then change it back to the original VTP domain name.
|
| Answer: | D. Change the switch to transparent mode then change it back to server mode.
E. Change the switchs VTP domain name and then change it back to the original VTP domain name.
|
| Explanation: | We can change the VTP revision number back to zero using one of the following methods:
- change the switch to transparent mode then change it back to server mode
- change the switchs VTP domain name and then change it back to the original VTP domain name |
|
| Question: | What are the 3 types of VTP advertisments?
A. Keepalive advertisments
B. Update advertisments
C. Summary advertisments
D. Advertisment requests from clients
E. Synchronization advertisments
F. Advertisment requests from transparent
G. Subset advertisments
|
| Answer: | C. Summary advertisments
D. Advertisment requests from clients
G. Subset advertisments
|
| Explanation: | VTP advertisments can occur in the following forms:
- summary advertisments, send every 300 seconds and when a database change occurs
- subset advertisments, send after a VLAN configuration change has occured
- advertisment requests from clients, clients requesting VLAN information |
|
| Question: | We want to configure the VTP domain Free-tests on our switch and advertisments have to be send secure using a password. How do we achieve this?
A. S1(config)#vtp domain Free-tests S1(config)#vtp mode server S1(config)#vtp password password
B. S1(config)#vtp domain Free-tests S1(config-vtp)#mode server S1(config-vtp)#password password
C. S1(config)#vtp domain Free-tests S1(config)#vtp mode server S1(config-vtp)#password password
D. S1(config)#vtp domain Free-tests S1(config)#vtp mode server S1(config)#vtp password password MD5
|
| Answer: | A. S1(config)#vtp domain Free-tests S1(config)#vtp mode server S1(config)#vtp password password
|
| Explanation: | We use the vtp domain domain_name configuration command to name the VTP domain. Using the vtp mode [server | client | transparent] command we set the mode of the switch and the vtp password password will set the domain to secure mode by using a password to send advertisments and validate received advertisments. |
|
| Question: | What are some of the benefits that VTP version 2 has over version 1?
A. Token ring support
B. Unrecognized TLV support
C. Mixed mode support
D. Version independant transparent mode
E. Authentication support
F. Encryption support
|
| Answer: | A. Token ring support
B. Unrecognized TLV support
|
| Explanation: | VTP version 2 offers the following additional features over version 1:
- version-dependant transparent mode
- token ring support
- consistency checks
- unrecognized TLV (type, length, value) support |
|
| Question: | Which command do we use to display the amount of VTP advertisments send?
A. show vtp advertisments
B. show vtp summary
C. show vtp counters
D. show vtp status
|
| Answer: | C. show vtp counters
|
| Explanation: | The show vtp counters command will display error counters and VTP messages. |
|
| Question: | By default which VLANs are eligible for pruning?
A. 1 to 1005
B. 1 to 4094
C. 1002 to 1005
D. 2 to 1001
E. 2 to 4094
|
| Answer: | D. 2 to 1001
|
| Explanation: | By default, VLANs 2 to 1001 are eligible for pruning, 1002 to 1005 are reserved for token ring and FDDI VLANs and are never eligible for pruning. |
|
| Question: | In our new network we dont want VLAN 5 to be pruned ever. How do we achieve this?
A. S1(config-if)#switchport trunk pruning vlan except 5
B. S1(config-if)#switchport mode trunk pruning vlan remove 5
C. S1(config)#switchport trunk pruning vlan except 5
D. S1(config)#switchport trunk pruning vlan remove 5
E. S1(config-if)#switchport mode trunk pruning vlan except 5
F. S1(config-if)#switchport trunk pruning vlan remove 5
|
| Answer: | A. S1(config-if)#switchport trunk pruning vlan except 5
|
| Explanation: | When pruning is enabled we can modify the default list of eligibility by using the switchport trunk pruning vlan {add | except | none | remove } vlan_list interface configuration command.
The keywords are defined as follows:
- all, all active VLANs are eligible
- add vlan_list, adds VLANs to an already configured list
- except vlan_list, all VLANs are eligible for pruninng except the VLANs listed
- remove vlan_list, removed VLANs from an already configued list
|
|
| Question: | Which command will display the VTP pruning state?
A. show interface type mod/num pruning
B. show vtp pruning
C. show pruning
D. show pruning vlan
|
| Answer: | A. show interface type mod/num pruning
|
| Explanation: | The show interface type mod/num pruning command will display the VTP pruning state. |
|
| Question: | Which of the following statements are true about EtherChannels?
A. All ports in the EtherChannel have to be trunks.
B. When trunks are used they can carry different VLANs.
C. Duplex settings have to be identical but speed settings can vary.
D. All bundled ports have to be in the same VLAN.
E. When trunks are used they must pass the same VLANs.
|
| Answer: | D. All bundled ports have to be in the same VLAN.
E. When trunks are used they must pass the same VLANs.
|
| Explanation: | When using ports to build the EtherChannel they need to belong to the same VLAN, trunks must carry the same VLANs and have the same native VLAN. The speed and duplex settings of the ports have to be same as before the creation of the EtherChannel and Spanning Tree settings have to be identical. |
|
| Question: | How do we configure EtherChannel load balancing based on destination IP Address?
A. S1(config)#port-channel load-balance dst-ip IP_Address
B. S1(config)#port-channel load-balance dst IP_Address
C. S1(config)#port-channel load-balance
D. S1(config)#port-channel load-balance dst-ip
|
| Answer: | D. S1(config)#port-channel load-balance dst-ip
|
| Explanation: | To configure load balancing on an EtherChannel we use the port-channel load-balance method configuration command.
The following methods can be used:
- src-ip, source IP Address
- dst-ip, destination IP Address
- src-dst-ip, source and destination IP Address
- src-mac, source MAC Address (Default)
- dst-mac, destination MAC Address
- src-dst-mac, source and destination MAC Address
- src-port, source port
- dst-port, destination port
- src-dst-port, source and destination port |
|
| Question: | Which protocols can be used to provide automatic EtherChannel configuration?
A. DTP
B. PAgP
C. DSCP
D. LACP
E. IGMP
F. NBAR
|
| Answer: | B. PAgP
D. LACP
|
| Explanation: | The two protocols used for automatic EtherChannel configuration are:
- PAgP, Port Aggregation Protocol (Cisco proprietary)
- LACP, Link Aggregation Control Protocol, IEEE802.3d |
|
| Question: | How do we configure a LACP EtherChannel?
A. S1(config)#lacp system-priority priority S1(config)#interface type mod/num S1(config-if)#channel-protocol lacp S1(config-if)#channel-group number mode auto
B. S1(config)#interface type mod/num S1(config-if)#lacp system-priority priority S1(config-if)#channel-protocol lacp S1(config-if)#channel-group number mode active
C. S1(config)#interface type mod/num S1(config-if)#lacp system-priority priority S1(config-if)#channel-protocol lacp S1(config-if)#channel-group number mode desirable
D. S1(config)#lacp system-priority priority S1(config)#interface type mod/num S1(config-if)#channel-protocol lacp S1(config-if)#channel-group number mode active
|
| Answer: | D. S1(config)#lacp system-priority priority S1(config)#interface type mod/num S1(config-if)#channel-protocol lacp S1(config-if)#channel-group number mode active
|
| Explanation: | When configuring a LACP EtherChannel the first thing we do is set the LACP system priority with the lacp system-priority priority global configuration command. We then use the channel-protocol lacp interface command to set the protocol.
We use the channel-group number mode [on | passive | active] interface configuration command to assign the channel group number to the interface.
The key words on unconditional LACP channel no negotiation, passive, listens passively and waits to be asked or active actively ask, are used to configure the channel negotiation. |
|
| Question: | In LACP the system priority is made up of?
A. 2-byte priority value
B. 6-byte switch MAC Address
C. 4-byte switch value
D. 2-byte port number
E. 6-byte priority value
F. 2-bit priority value
G. 4-byte priority value
|
| Answer: | A. 2-byte priority value
B. 6-byte switch MAC Address
|
| Explanation: | In LACP the switch priority consists of a 2-byte priority value followed by a 6-byte switch MAC Address. |
|
| Question: | Which command do we use to verify EtherChannel negotiation?
A. show etherchannel negotiation
B. show etherchannel
C. show etherchannel interface
D. show etherchannel port
|
| Answer: | D. show etherchannel port
|
| Explanation: | The show etherchannel port command will display the channel negotiation mode. |
|
| Question: | Which command will display the LACP system ID?
A. show lacp system-id
B. show lacp
C. show lacp system
D. show lacp sys-id
|
| Answer: | D. show lacp sys-id
|
| Explanation: | The show lacp sys-id command will display the LACP system ID. |
|
| Question: | When an unknown unicast is received on a bridge port. What will the bridge do with that frame?
A. It will send it out of all the bridge ports.
B. It will return an icmp unreachable to the source.
C. It will drop the frame.
D. It will send it out of all its ports except the one it received the frame on.
|
| Answer: | D. It will send it out of all its ports except the one it received the frame on.
|
| Explanation: | When an unknown unicast, the destination address is not in the bridge table, the frame will be send out all of the bridge ports except the port it was received on. |
|
| Question: | Which of the following are BPDUs?
A. Hello BPDU
B. Topology Change Notification BPDU
C. Configuration Change Notification BPDU
D. Configuration BPDU
E. Topology Control BPDU
|
| Answer: | B. Topology Change Notification BPDU
D. Configuration BPDU
|
| Explanation: | There are 2 type of BPDUs:
- Configuration BPDU
- Topology Change Notifications |
|
| Question: | What do we call the manipulation of packets to obtain different QoS values?
A. Marking
B. Scheduling
C. Policing
D. Classification
|
| Answer: | A. Marking
|
| Explanation: | When we need to manipulate the QoS value of classified packets to obtain different values we call it marking. |
|
| Question: | How do we enable QoS on a switch?
A. switch(config)#mls qos
B. switch(config)#qos enable
C. switch(config)#enable qos
D. no configuration needed, qos is enabled by default
|
| Answer: | A. switch(config)#mls qos
|
| Explanation: | The mls qos global configuration command will enable QoS on a switch. |
|
| Question: | The default bridge priority on a Catalyst switch is?
A. 32768
B. 65535
C. 0
D. 32769
E. 65534
|
| Answer: | A. 32768
|
| Explanation: | The default bridge priority is 32768 and can have a value between 0 and 65535. |
|
| Question: | What are the 2 components of the Bridge ID?
A. VLAN1 IP Address
B. MAC Address
C. Highest IP Address configured on the switch.
D. Bridge Priority
E. Highest MAC Address in the CAM table
|
| Answer: | B. MAC Address
D. Bridge Priority
|
| Explanation: | The bridge ID consists of:
- Bridge Priority
- MAC Address |
|
| Question: | A root port is a port that has _________ .
A. the highest port cost
B. the lowest root path cost
C. the highest root path cost
D. the lowest port cost
|
| Answer: | B. the lowest root path cost
|
| Explanation: | A root port is the port that has the lowest root path cost to the root bridge. The root path cost is the cummalative cost of all links leading to the root bridge. |
|
| Question: | Using the new STP cost scale, what is the STP cost of a 622 Mbps link?
A. 14
B. 4
C. 19
D. 6
E. 2
|
| Answer: | D. 6
|
| Explanation: | | Link Bandwidth | Old STP cost | New STP cost | | 4 Mbps | 250 | 250 | | 10 Mbps | 100 | 100 | | 16 Mbps | 63 | 62 | | 45 Mbps | 22 | 39 | | 100 Mbps | 10 | 19 | | 155 Mbps | 6 | 14 | | 622 Mbps | 2 | 6 | | 1 Gbps | 1 | 4 | | 10 Gbps | 0 | 2 | |
|
| Question: | When there is more then 1 switch on the same segment, they will elect besides a root port also a ________ port.
A. designated
B. nominated
C. backup
D. standby
|
| Answer: | A. designated
|
| Explanation: | When there is more then 1 switch that have ports connected to the same network segment they will elect a designated port to forward traffic from that segment. |
|
| Question: | Associate each state with its description
A. the port cannot add send or receive data,the port is allowed to send and receive BPDUs,the port can send and receive data,the port can add MAC addresses,the port is administratively shutdown
B. Blocking, Listening, Forwarding, Learning, Disabled
|
| Answer: | B. Blocking, Listening, Forwarding, Learning, Disabled
|
| Explanation: | | State | Description | | Disabled | In this state the port is administratively shutdown | | Blocking | In this state the port cannot add send or receive data | | Listening | In this state the port is allowed to send and receive BPDUs | | Learning | In this state the port can add MAC addresses, | | Forwarding | In this state the port can send and receive data | |
|
| Question: | Which debug command will show the transitioning of the port states?
A. debug spanning-tree state
B. debug spanning-tree bpdu
C. debug spanning-tree root
D. debug spanning-tree switch state
|
| Answer: | D. debug spanning-tree switch state
|
| Explanation: | The debug spanning-tree switch state will display the transistioning between the port states. The show spanning-tree interface command is not fast enough to display the transistioning. |
|
| Question: | The default Max Age value is?
A. 50 seconds
B. 15 seconds
C. 2 seconds
D. 10 seconds
E. 30 seconds
F. 20 seconds
|
| Answer: | F. 20 seconds
|
| Explanation: | The default Max Age time is 20 seconds, default Forwarding Delay is 15 seconds and Hellos are send every 2 seconds by default. |
|
| Question: | The default timers of STP (Hello, Forwarding Delay and Max Age) are based on an assumption of the diameter of the network. How much is that diameter?
A. 3
B. 10
C. 15
D. 5
E. 9
F. 7
|
| Answer: | F. 7
|
| Explanation: | The timers are based on the assumption that the network has a diameter of 7 switches. |
|
| Question: | This is the time a port is in both listening and learning state.
A. Forward Delay
B. Max Age
C. Hello
D. Transition Delay
|
| Answer: | A. Forward Delay
|
| Explanation: | The Forward Delay is the time that a port is in both Listening and Learning state. The default value is 15 seconds. |
|
| Question: | When is TCN BPDU sent?
A. When a port moves from Listening to Learning state.
B. When a port moves from Blocking into Listening state.
C. When a port moves from Forwarding or Learning state into Blocking state.
D. When a port moves into Forwarding state.
|
| Answer: | C. When a port moves from Forwarding or Learning state into Blocking state.
D. When a port moves into Forwarding state.
|
| Explanation: | A topology change occurs when a port is put into Forwarding state or a port that is in Forwarding or Learning state goes into Blocking state. Both these events will trigger a TCN (Topology Change Notification) BPDU to be send. |
|
| Question: | Which of the following Spanning Tree types is Cisco Proprietary?
A. PVST
B. CST
C. STP
D. RSTP
|
| Answer: | A. PVST
|
| Explanation: | PVST or Per-VLAN Spanning Tree is Ciscos proprietary version of the Spanning Tree protocol. |
|
| Question: | Which of the following statements are correct?
A. PVST requires ISL.
B. PVST can use both ISL and 802.1Q.
C. Multiple Spanning Trees allows for load balancing over redundant links.
D. PVST can coexist with CST.
|
| Answer: | A. PVST requires ISL.
C. Multiple Spanning Trees allows for load balancing over redundant links.
|
| Explanation: | Due to the PVST being Cisco proprietary it requires ISL for trunking.
Multiple Spanning Trees allows for load balancing over redundant links when the links are assigned to different VLANs.
PVST+ was developped to coexist with CST. |
|
| Question: | When root path cost is the same for 2 ports what sequence will be used to determine the root port?
A. 1,2,3,4
B. lowest root bridge ID, lowest root path cost, lowest sender bridge ID, lowest sender port ID
|
| Answer: | B. lowest root bridge ID, lowest root path cost, lowest sender bridge ID, lowest sender port ID
|
| Explanation: | All STP decisions are based on the following sequence of four conditions:
1. Lowest Root Bridge ID
2. Lowest Root Path Cost
3. Lowest Sender Bridge ID
4. Lowest Sender Port ID |
|
| Question: | How do we enable spanning tree on a new switch?
A. switch(config)#spanning-tree vlan 1
B. switch(config)#spanning-tree enable
C. Spanning tree is enabled by default.
D. switch(config)#spanning-tree vlan enable
|
| Answer: | C. Spanning tree is enabled by default.
|
| Explanation: | On a new switch spanning tree is enabled by default. If for some reason spanning was disabled we use the spanning-tree vlan vlan id global configuration command to re-enable spanning tree. |
|
| Question: | Which two methods can we use to configure the root bridge?
A. switch(config)#spanning-tree priority bridge-priority
B. switch(config)#spanning-tree vlan vlan id root-priority bridge-priority
C. switch(config)#spanning-tree vlan vlan id priority bridge-priority
D. switch(config)#spanning-tree vlan vlan id root
|
| Answer: | C. switch(config)#spanning-tree vlan vlan id priority bridge-priority
D. switch(config)#spanning-tree vlan vlan id root
|
| Explanation: | We can use the following commands to configure a root bridge:
- switch(config)#spanning-tree vlan vlan id priority bridge-priority
- switch(config)#spanning-tree vlan vlan id root {primary|secondary}
|
|
| Question: | When using the primary keyword with the following command spanning-tree vlan vlan id root primary on our new 3550 switch what will be its bridge priority if you know that the current bridge has a priority of 20000.
A. 19999
B. 0
C. 1
D. 15904
|
| Answer: | D. 15904
|
| Explanation: | When we use the primary keyword the bridge priority will become 24576 if the current root bridge has a priority higher then that. If the current root bridge has a priority less then that, the new bridge priority will become 4096 less then the current root bridge priority. |
|
| Question: | In a good network design the root bridge is placed where?
A. Closest to the users.
B. On the most powerfull switch.
C. On the busiest segment.
D. Closest to the server farm.
E. In the center of the network.
|
| Answer: | E. In the center of the network.
|
| Explanation: | In a good network design the root bridge is placed in the center of the Layer 2 network. |
|
| Question: | When want to change the root path for a switch in Vlan 5. How do we achieve this? Be aware that this switch is also a member of other Vlans.
A. switch(config-if)#spanning-tree vlan 5 cost cost
B. switch(config)#spanning-tree vlan 5 cost cost
C. switch(config-if)#spanning-tree vlan 5 cost
D. switch(config-vlan)#spanning-tree cost cost
|
| Answer: | A. switch(config-if)#spanning-tree vlan 5 cost cost
|
| Explanation: | The spanning-tree [vlan vlan id] cost cost interface configuration command will change the cost of a port on a switch. The vlan keyword the port cost is only modified for that vlan. |
|
| Question: | What is the default port priority on a switch?
A. 128
B. 0
C. 256
D. 255
|
| Answer: | A. 128
|
| Explanation: | The port priority is a value between 0 and 255, by default it is 128. |
|
| Question: | How do we change the port priority on a switch?
A. switch(config)#spanning-tree port-priority value
B. switch(config-vlan)#spanning-tree port-priority value
C. switch(config-if)#spanning-tree port-priority value
D. switch(config-if)#spanning-tree priority value
|
| Answer: | C. switch(config-if)#spanning-tree port-priority value
|
| Explanation: | To change the switch port priority we use the spanning-tree [vlan vlan id] port-priority value interface configuration command. If the vlan keyword is omitted the port priority is set for all active VLANs. |
|
| Question: | How do we change the Hello timer of Spanning Tree?
A. switch(config)#spanning-tree hello-interval seconds
B. switch(config-if)#spanning-tree hello-time seconds
C. switch(config)#spanning-tree hello-time seconds
|
| Answer: | C. switch(config)#spanning-tree hello-time seconds
|
| Explanation: | We use the global spanning-tree [vlan vlan id] hello-time seconds configuration command to change the interval. |
|
| Question: | When modifying the Spanning Tree timers we make these changes on ______.
A. any switch in the network, not necessarly the root bridge.
B. on the fastest switch.
C. the root bridge only.
D. every switch in the network.
|
| Answer: | C. the root bridge only.
|
| Explanation: | Modifying the Spanning Tree timers only has to be done on the root bridge. The timers will be propagated through the network via Configuration BPDUs. |
|
| Question: | The default value of the Max Age timer is 20 seconds, what is the minimum and maximum value?
A. 6
B. 40
C. 50
D. 15
E. 20
F. 1
|
| Answer: | A. 6
B. 40
|
| Explanation: | The Max Age timer can be set between 6 and 40 seconds. |
|
| Question: | What can we enable on an access switch to put a port immediately in forwarding state?
A. UplinkFast
B. BackboneFast
C. RSTP
D. Portfast
|
| Answer: | D. Portfast
|
| Explanation: | PortFast is used to bring a port on an access switch immediately to forwarding state. |
|
| Question: | When we have a redundant path to the root bridge how can we speed up the process to get the next root port start forwarding traffic?
A. Implement UplinkFast
B. Implement BackboneFast
C. Implement PortFast
D. This can not be done
|
| Answer: | A. Implement UplinkFast
|
| Explanation: | When using UplinkFast the switch keeps a records of all parallel paths to the root bridge, if the primary uplink fails it will bring the next-lowest cost rooth path out of blocking state and into forwarding state. |
|
| Question: | How do we enable UplinkFast on a switch?
A. switch(config)#spanning-tree uplinkfast
B. switch(config)#spanning-tree uplink-fast
C. switch(config-if)#spanning-tree uplink-fast
D. switch(config-vlan)#spanning-tree uplinkfast
E. switch(config-vlan)#spanning-tree uplink-fast
F. switch(config-if)#spanning-tree uplinkfast
|
| Answer: | A. switch(config)#spanning-tree uplinkfast
|
| Explanation: | To enable UplinkFast we use the spanning-tree uplinkfast global configuration command. |
|
| Question: | When enabling the UplinkFast feature what will be done on the switch?
A. The bridge priority is lowered to 32767.
B. The port cost is increased to 3000.
C. The bridge priority is raised to 49152.
D. The port cost is increased by 3000.
|
| Answer: | C. The bridge priority is raised to 49152.
D. The port cost is increased by 3000.
|
| Explanation: | When enabling the UplinkFast feature the bridge priority is raised to 49152 so it becomes unlikely that the switch will become the root bridge. Port cost is increased by 3000 making them undesirable for downstream neighbors to use them as paths to the root. |
|
| Question: | BackboneFast uses which protocol to determine if upstream neighbors have a stable path to the root bridge?
A. Discovery Protocol
B. Root Discovery Protocol
C. Root Link Query
D. BPDUs
|
| Answer: | C. Root Link Query
|
| Explanation: | BackboneFast uses the Root Link Query protocol to determine if upstream neighbors have a stable path to the root bridge. |
|
| Question: | BackboneFast has to be enabled on ______________.
A. every switch in the network
B. the root bridge
C. the core switches only
D. nowhere, it is enabled by default
|
| Answer: | A. every switch in the network
|
| Explanation: | BackboneFast has to be enabled on every switch in the network because it relies on the Root Link Query request and reply mechanism. BackboneFast is disabled by default. |
|
| Question: | Which command will display the designated ports?
A. show spanning-tree brief
B. show spanning-tree
C. show spanning-tree summary
D. show spanning-tree port
|
| Answer: | A. show spanning-tree brief
|
| Explanation: | The show spanning-tree [vlan vlan id] brief will show the designated ports and designated bridge IDs on each port. |
|
| Question: | Which command will display the total number of switch ports in each STP state?
A. show spanning-tree ports detail
B. show spanning-tree brief
C. show spanning-tree port
D. show spanning-tree summary
|
| Answer: | D. show spanning-tree summary
|
| Explanation: | The show spanning-tree [vlan vlan id] summary will display the total number of switch ports in each STP state. |
|
| Question: | In STP which best describes a blocked port?
A. A port that neither the root or designated port.
B. A port that is not running spanning tree.
C. A port that has a normal end user connection.
D. A port that is administratively shutdown.
|
| Answer: | A. A port that neither the root or designated port.
|
| Explanation: | A blocked port is a port that is not the root port or a designated port. |
|
| Question: | How do we enable the Root Guard feature?
A. switch(config-if)#spanning-tree rootguard
B. switch(config-if)#spanning-tree root guard
C. switch(config-if)#spanning-tree guard root
D. switch(config-if)#spanning-tree root guard enable
|
| Answer: | C. switch(config-if)#spanning-tree guard root
|
| Explanation: | To enable the Root Guard feature we use the spanning-tree guard root interface configuration command. |
|
| Question: | What does the Root Guard feature provide?
A. A port will always become a designated port.
B. A port will only be able to receive BPDUs and not forward them.
C. A port will always become the root port.
D. A port will only be able to relay BPDUs not receive them.
|
| Answer: | D. A port will only be able to relay BPDUs not receive them.
|
| Explanation: | Root Guard designates that a port can only relay BPDUs and not receive them. |
|
| Question: | When BPDU Guard is enabled what will happen to the port when a BPDU is received on that port?
A. The port is put into blocking state.
B. The port is sending the BPDU back to the sender.
C. The port is put into errdisable state.
D. The port is put into listening state.
|
| Answer: | C. The port is put into errdisable state.
|
| Explanation: | When a BPDU is received on a port with BPDU guard enabled the port is put into errdisable state. |
|
| Question: | Which STP feature is described by the following: "The measurement of the amount of time that elapses from the time a BPDU is expected to when it actually arrives".
A. Rapid Spanning Tree
B. Loop Guard
C. BPDU skew detection
|
| Answer: | C. BPDU skew detection
|
| Explanation: | BPDU skew detection measures the amount of time that elapses from the time a BPDU is expected to when it actually arrives. This time difference is called the skew time. |
|
| Question: | What can we put in place to prevent the following: A blocked port is receiving BPDUs, the flow of BPDUs stop and the last BPDU is flushed and goes through the STP states and starts forwarding traffic.
A. BPDU Guard
B. Link Guard
C. Root Guard
D. Loop Guard
|
| Answer: | D. Loop Guard
|
| Explanation: | To prevent the following behaviour that a blocked port is receiving BPDUs and the flow of BPDUs stop then the last BPDU is flushed and goes through the STP states and starts forwarding traffic we can implement Loop Guard. |
|
| Question: | The message interval of the UDLD feature can be configured between which values?
A. 10 seconds
B. 2 seconds
C. 15 seconds
D. 7 seconds
E. 90 seconds
F. 30 seconds
G. 20 seconds
|
| Answer: | D. 7 seconds
E. 90 seconds
|
| Explanation: | The default message interval of UDLD (unidirectional link detection) is 15 seconds on a Catalyst 4500 and 6500, 7 seconds on Catalyst 3550. The interval can be configured between 7 and 90 seconds. |
|
| Question: | Which of the following are UDLD modes of operation?
A. Quiet
B. Silent
C. Desirable
D. Normal
E. Aggressive
|
| Answer: | D. Normal
E. Aggressive
|
| Explanation: | The two modes of UDLD operation are:
- Normal
- Aggressive |
|
| Question: | How do we enable UDLD in normal mode on our fibre optic switch (ie all ports are fibre optic)?
A. switch(config)#udld enable
B. switch(config-if)#udld mode normal
C. switch(config)#udld mode normal
D. switch(config)#udld mode normal enable
|
| Answer: | A. switch(config)#udld enable
|
| Explanation: | If all our ports are fibre optic ports then we can enable udld in global configuration mode using the udld enable command. |
|
| Question: | On a Catalyst 3550 switch the default UDLD message time interval is?
A. 7 seconds
B. 5 seconds
C. 2 seconds
D. 30 seconds
E. 15 seconds
F. 10 seconds
|
| Answer: | A. 7 seconds
|
| Explanation: | By default the UDLD message time interval is 7 seconds on a Catalyst 3550 on Catalyst 4500 and 6500 the default is 15 seconds. |
|
| Question: | How do we enable ports that are put in errdisable state by UDLD?
A. udld reset
B. clear udld
C. udld enable
D. clear udld *
|
| Answer: | A. udld reset
|
| Explanation: | To re-enable ports that UDLD aggressive mode has put into errdisable state we use the udld reset command. |
|
| Question: | How do we display the global BPDU guard state?
A. show spanning-tree summary
B. show spanning-tree guard
C. show spanning-tree bpduguard
D. show spanning-tree interface
|
| Answer: | A. show spanning-tree summary
|
| Explanation: | The show spanning-tree summary command will display the global BPDU guard state. |
|
| Question: | What is described by the following:
"This is the variation in the amount of delay so packets are not arriving at predictable times"
A. Delay
B. Loss
C. Variance
D. Jitter
|
| Answer: | D. Jitter
|
| Explanation: | The variation in delay is called Jitter. |
|
| Question: | Which of the following are QoS types?
A. Integrated DiffServ
B. DSCP value manipulation
C. Differential Services
D. Best Effort
E. Differentiated Services
|
| Answer: | D. Best Effort
E. Differentiated Services
|
| Explanation: | The three types of QoS are:
- Best Effort
- Integrated Services model
- Differentiated Services model |
|
| Question: | Integrated Services is associated with which protocol?
A. CGMP
B. ATM
C. RSVP
D. RSTP
E. TCP
|
| Answer: | C. RSVP
|
| Explanation: | Integrated services is associated with RSVP, Resource Reservation Protocol, described in RFC 1633. |
|
| Question: | Using ISL the CoS is entered where?
A. Three bits are added to the User Field
B. The lower three bytes of the User Field
C. The upper three bytes of the User Field
D. Three bytes are added to the User Field
E. The lower three bits of the User Field
F. The upper three bits of the User Field
|
| Answer: | E. The lower three bits of the User Field
|
| Explanation: | The lower three bits of the User Field are used as a CoS value. |
|
| Question: | The ToS byte is divided into?
A. 4 bit IP Presedence
B. 3 bit ToS value
C. 3 bit IP Presedence
D. 4 bit ToS value
E. 5 bit ToS value
F. 5 bit IP Presedence
|
| Answer: | C. 3 bit IP Presedence
D. 4 bit ToS value
|
| Explanation: | The ToS byte [Type of Service] is divided into a 3 bit IP Presedence value and 4 bit ToS value. |
|
| Question: | DSCP is the abbreviation of?
A. Differentiated Service Code Protocol
B. Differentiated Service Classification Point
C. Differentiated Service Classification Protocol
D. Differentiated Service Code Point
|
| Answer: | D. Differentiated Service Code Point
|
| Explanation: | DSCP stands for Differentiated Services Code Point |
|
| Question: | Which are of the following are part of the DSCP value?
A. 3 bit IP Presedence
B. 3 bit Drop Presedence
C. 3 bit ToS value
D. 3 bit Class Selector
E. 3 bit CoS value
|
| Answer: | B. 3 bit Drop Presedence
D. 3 bit Class Selector
|
| Explanation: | The DSCP value is divided into a 3 bit Class Selector and 3 bit Drop Presedence. |
|
| Question: | Match the IP Presedence value with the name
A. Routine, Priority, Immediate, Flash, Flash override, Critical, Internetwork Control, Network Control
B. 0,1,2,3,4,5,6,7
|
| Answer: | A. Routine, Priority, Immediate, Flash, Flash override, Critical, Internetwork Control, Network Control
|
| Explanation: | | Name | Value | | Routine | 0 | | Priority | 1 | | Immediate | 2 | | Flash | 3 | | Flash Override | 4 | | Critical | 5 | | Internetwork Control | 6 | | Network Control | 7 | |
|
| Question: | An IP Presedence value of 3 corresponds with?
A. Flash
B. Network Control
C. Immediate
D. Critical
|
| Answer: | A. Flash
|
| Explanation: | | Name | Value | | Routine | 0 | | Priority | 1 | | Immediate | 2 | | Flash | 3 | | Flash Override | 4 | | Critical | 5 | | Internetwork Control | 6 | | Network Control | 7 | |
|
| Question: | When using the Class Selector field, a value of 5 is also known as?
A. Best Effort
B. Assured Forwarding
C. Expedited Forwarding
D. Internetwork Control
|
| Answer: | C. Expedited Forwarding
|
| Explanation: | The Class Selector is divided into:
Class 0, Best Effort
Class 1 through 4 are Assured Forwarding
Class 5, Expedited Forwarding
Class 6 & 7 or Internetwork Control & Network Control |
|
| Question: | What methods can we use to rate-limit traffic?
A. Aggregate Policers
B. Microflow Policers
C. Weighted Fair Queue
D. Weighted Policers
E. Weighted Round Robin
|
| Answer: | A. Aggregate Policers
B. Microflow Policers
|
| Explanation: | We use traffic policers to rate-limit traffic. We can use either microflow policers or aggregate policers. |
|
| Question: | Which two methods can we use for congestion avoidance?
A. Tail Drop
B. Weighted Round Robin
C. Weighted Random Early Detection
D. Aggregate Policers
E. FIFO
|
| Answer: | A. Tail Drop
C. Weighted Random Early Detection
|
| Explanation: | A switch can avoid congestion using one of the following methods:
- Tail Drop
- Weighted Random Early Detection |
|
| Question: | Scheduling, in a QoS way is also known as?
A. Ingress Queueing
B. Congestion Management
C. Congestion Avoidance
D. Egress Queueing
E. Tail Drop
|
| Answer: | B. Congestion Management
D. Egress Queueing
|
| Explanation: | Congestion Management or Egress Queueing is also known as Scheduling. |
|
| Question: | When a switch port has the following queue type notation, 1p2q2t. What are its queues?
A. 1 strict priority 2 standard queues 2 WRED
B. 1 strict priority 2 standard queues 2 WRR
C. 1 strict priority 2 WRR 2 WRED
D. 1 strict priority 2 standard queues 2 Tail drop
|
| Answer: | A. 1 strict priority 2 standard queues 2 WRED
|
| Explanation: | The switch queue type notation consists of the following:
- p, the number of strict priority queues
- q, the number of standard queues
- t, the number of configurable WRED thresholds per standard queue |
|
| Question: | Which command do we use to view what type of egress queues are available?
A. show interface type/mod summary
B. show interface type/mod switchport
C. show interface type/mod capabilities
D. show interface type/mod flowcontrol
|
| Answer: | C. show interface type/mod capabilities
|
| Explanation: | The show interface type/mod capabilities command will display the available types of egress queueing on IOS based switches. |
|
| Question: | How do we make sure only the DSCP value is used for QoS on a switchport?
A. switch(config-if)#mls qos dscp
B. switch(config-if)#qos trust dscp
C. switch(config-if)#mls qos scp trust
D. switch(config-if)#mls qos trust dscp
|
| Answer: | D. switch(config-if)#mls qos trust dscp
|
| Explanation: | The mls qos trust {cos | dscp | ip-presendence} is used to define consistent QoS trust. |
|
| Question: | How do we convert IP Presedence settings to our desired DSCP values?
A. switch(config)#mls qos map ip-prec-dscp dscp values
B. switch(config)#mls qos ip-prec-dscp dscp values
C. switch(config)#mls qos map dscp-ip-prec dscp values
D. switch(config)#mls qos map ip-presedence dscp dscp values
|
| Answer: | A. switch(config)#mls qos map ip-prec-dscp dscp values
|
| Explanation: | We use the mls qos map ip-prec-dscp dscp values global configuration command to map the IP Presedence values to internal (non-default) DSCP values. |
|
| Question: | How do we classify traffic with an access-list?
A. switch(config-cmap)#match access-group access-list
B. switch(config-cmap)#match access-group name access-list
C. switch(config-cmap)#match access-list
D. switch(config-cmap)#match access-list name access-list
|
| Answer: | B. switch(config-cmap)#match access-group name access-list
|
| Explanation: | When we use an access-list to classify traffic we use the match access-group name access-list in class map configuration mode. |
|
| Question: | How do we classify traffic using NBAR?
A. switch(config)#match protocol protocol name
B. switch(config-cmap)#match nbar protocol name
C. switch(config-cmap)#match protocol protocol name
D. switch(config-pmap)#match protocol protocol name
|
| Answer: | C. switch(config-cmap)#match protocol protocol name
|
| Explanation: | When we use NBAR to classify traffic we use the match protocol protocol name in class map configuration mode. |
|
| Question: | What command will define a QoS policy?
A. switch(config)#class-map class-name
B. switch(config-cmap)#policy-map policy-name
C. switch(config)#policy-map policy-name
D. switch(config-pmap)#policy-map policy-name
|
| Answer: | C. switch(config)#policy-map policy-name
|
| Explanation: | To define a QoS policy we use the policy-map policy-name global configuration command. |
|
| Question: | How do we apply a QoS policy to an interface?
A. switch(config-if)#policy policy-name
B. switch(config-if)#service-policy policy-name inbound
C. switch(config-if)#policy-map policy-name
D. switch(config-if)#service-policy policy-name
|
| Answer: | D. switch(config-if)#service-policy policy-name
|
| Explanation: | To apply a QoS policy to an interface we use theservice-policy [input | output] policy-name interface configuration command. |
|
| Question: | What are the two default weights of the standard queues of an interface?
A. 16
B. 32
C. 64
D. 128
E. 256
F. 1
G. 255
H. 4
|
| Answer: | G. 255
H. 4
|
| Explanation: | The default value of the weight of standard queues on an interface are 4 and 255. |
|
| Question: | How can we change the weight of the standard queues on an interface?
A. switch(config-if)#default-queue bandwidth weight1 weight 2
B. switch(config-if)#wrr-queue bandwidth weight1 weight 2
C. switch(config-if)#wrr-queue weight1 weight 2
D. switch(config-if)#qos-queue bandwidth weight1 weight 2
|
| Answer: | B. switch(config-if)#wrr-queue bandwidth weight1 weight 2
|
| Explanation: | In order to change the default weights of the standard queues on an interface we use the wrr-queue bandwidth weight1 weight 2 interface configuration command. The values can vary between 1 and 255. |
|
| Question: | How do we enable tail drop on an interface?
A. switch(config-if)#mls qos tail-drop enable
B. switch(config-if)#mls qos tail-drop
C. switch(config-if)#wrr-queue random-detect queue id
D. switch(config-if)#no wrr-queue random-detect queue id
|
| Answer: | D. switch(config-if)#no wrr-queue random-detect queue id
|
| Explanation: | To enable tail drop we use the following interface configuration command no wrr-queue random-detect queue id. |
|
| Question: | How do we enable the egress expedite queue?
A. switch(config-if)#strict-priority-queue out
B. switch(config-if)#mls qos priority-queue out
C. switch(config-if)#priority-queue out
D. switch(config-if)#mls priority-queue out
|
| Answer: | C. switch(config-if)#priority-queue out
|
| Explanation: | To enable the strict-priority queue or egress expedite queue we use the priority-queue out interface configuration command. |
|
| Question: | How do we verify the QoS settings on an interface?
A. show mls qos interface
B. show mls interface
C. show mls interface detail
D. show interface
|
| Answer: | A. show mls qos interface
|
| Explanation: | To verify the QoS settings on an interface we use the show mls qos interface type mod/num command. |
|
| Question: | RSTP is defined by which IEEE standard?
A. 802.1w
B. 802.5
C. 802.1s
D. 802.1d
|
| Answer: | A. 802.1w
|
| Explanation: | RSTP or Rapid Spanning Tree is defined by IEEE 802.1w. |
|
| Question: | In RSTP what is the name of a port that has a less desirable but redundant path to a segement where another switch port already connects?
A. Backup port
B. Redundant port
C. Alternate port
D. Designated port
|
| Answer: | A. Backup port
|
| Explanation: | A backup port is the name of a port that has a less desirable but redundant path to a segement where another switch port already connects when using RSTP. |
|
| Question: | When a port is in Discarding state in RSTP that same port would be in which state(s) using STP?
A. Learning
B. Forwarding
C. Disabled
D. Blocking
E. Listening
|
| Answer: | C. Disabled
D. Blocking
E. Listening
|
| Explanation: | When a port is in Discarding state in RSTP that same port would be in Disabled, Blocking and Learning state when using STP. |
|
| Question: | When portfast and RSTP is enabled on a switch port we call that port?
A. Edge port
B. Alternate port
C. Point-to-point port
D. Backup port
|
| Answer: | A. Edge port
|
| Explanation: | An edge port is is a switch port where a single host connects and has been identified by enabling the STP portfast feature. |
|
| Question: | When RSTP is synchronizing what type of messages are sent using configuration BPDUs?
A. configuration message
B. agreement message
C. acceptance message
D. proposal message
E. information message
|
| Answer: | B. agreement message
D. proposal message
|
| Explanation: | During the synchronization process of RSTP proposal and agreements are send using configuration BPDUs. |
|
| Question: | When does RSTP detect a topology change?
A. When an edge port changes to forwarding state.
B. When an edge port changes to blocking state.
C. When a nonedge port changes to forwarding state.
D. When an nonedge port changes to blocking state.
|
| Answer: | C. When a nonedge port changes to forwarding state.
|
| Explanation: | RSTP detects a topology change only when a nonedge port changes to forwarding state. |
|
| Question: | When a switch receives a BPDU with a TC bit set what will happen?
A. BPDUs with the TC bit set are sent out for 4 times the hello time.
B. BPDUs with the TC bit set are sent out for 6 times the hello time.
C. MAC addresses are flushed from the CAM.
D. MAC addresses associated with designated port the BPDU are flushed from the CAM.
|
| Answer: | C. MAC addresses are flushed from the CAM.
|
| Explanation: | When a switch receives a BPDU with the TC bit set it flushes all the MAC addresses associated with those nonedge designated ports. |
|
| Question: | How can we change a half-duplex port to a point-to-point port in RSTP?
A. switch(config-if)#spanning-tree port-type point-to-point
B. switch(config-if)#spanning-tree port point-to-point
C. switch(config-if)#spanning-tree link-type point-to-point
D. switch(config-if)#spanning-tree point-to-point
|
| Answer: | C. switch(config-if)#spanning-tree link-type point-to-point
|
| Explanation: | To configure a half-duplex to be a point-to-point link we use the spanning-tree link-type point-to-point interface configuration command. |
|
| Question: | Using PVST+, 500 VLANs and 350 are active how many instances of spanning tree are running?
A. 500
B. 1
C. 350
D. Can not tell
|
| Answer: | C. 350
|
| Explanation: | When using PVST+ an instance of spanning will be running for each active VLAN. |
|
| Question: | Which attributes have to be indentical on each switch running MST region?
A. configuration name
B. revision number
C. instance-to-Vlan mapping table
D. region name
E. domain name
F. Vlan-to-instance mapping table
|
| Answer: | A. configuration name
B. revision number
C. instance-to-Vlan mapping table
|
| Explanation: | Within a region all switches must run the instance of MST that is defined by the following attributes:
- MST configuration name
- MST configuration revision number
- MST instance-to-Vlan mapping table |
|
| Question: | How do we enable MST on a switch?
A. switch(config)#spanning-tree mode mst
B. switch(config)#spanning-tree mst configuration
C. switch(config)#spanning-tree mst
D. switch(config)#mst enable
|
| Answer: | A. switch(config)#spanning-tree mode mst
|
| Explanation: | To enable MST on a switch we use the spanning-tree mode mst global configuration command. |
|
| Question: | How do we assign the mst revision number?
A. switch(config)#spanning-tree mst revision version
B. switch(config-mst)#spanning-tree revision version
C. switch(config-mst)#spanning-tree mst revision version
D. switch(config-mst)#revision version
|
| Answer: | D. switch(config-mst)#revision version
|
| Explanation: | In order to assign the MST revision number we use the revision version MST configuration command. |
|
| Question: | How do we change the bridge priority in mst?
A. switch(config)#spanning-tree mst instance_id priority bridge_priority
B. switch(config)#spanning-tree mst priority bridge_priority instance instance_id
C. switch(config)#spanning-tree mst priority bridge_priority
D. switch(config-mst)#instance_id priority bridge_priority
|
| Answer: | A. switch(config)#spanning-tree mst instance_id priority bridge_priority
|
| Explanation: | To change the bridge priority we use the spanning-tree mst instance_id priority bridge_priority global configuration command. |
|
| Question: | How do we change the forward delay timer in MST?
A. switch(config)#spanning-tree mst forward-delay seconds
B. switch(config-mst)#spanning-tree mst forward-delay seconds
C. switch(config)#spanning-tree mst instance instance_id forward-time seconds
D. switch(config)#spanning-tree mst instance instance_id forward-delay seconds
E. switch(config)#spanning-tree mst forward-time seconds
F. switch(config-mst)#spanning-tree mst forward-time seconds
|
| Answer: | E. switch(config)#spanning-tree mst forward-time seconds
|
| Explanation: | To change the forward delay timer in MST we use the spanning-tree mst forward-time seconds global configuration command. Changing timers are for MST as a whole not for individual MST instances. |
|
| Question: | What is used in a single, loop-free topology inside a MST region?
A. Common Spanning Tree
B. Instance Spanning Tree
C. Internal Spanning Tree
D. Per Vlan Spanning Tree
|
| Answer: | C. Internal Spanning Tree
|
| Explanation: | Internal Spanning Tree (IST) is used like CST (Common Spanning Tree) to maintain a single, loop-free topology inside a MST region. |
|
| Question: | When a multilayer switch assigns a layer 3 address to a logical interface that represents an entire VLAN it is called a _____________.
A. Switched Virtual Interface
B. Switched VLAN Interface
C. Stacked Virtual Interface
D. Integrated Routing & Bridging Interface
|
| Answer: | A. Switched Virtual Interface
|
| Explanation: | When a multilayer switch assigns a layer 3 address to a logical interface that represents an entire VLAN it is called a switched virtual interface. |
|
| Question: | On our Catalyst 3550 we used one of the ports as a layer 3 port. We do not need this requirement anymore and want to change it back to a layer 2 port. How do we achieve this
A. switch(config-if)#switchport mode layer-2
B. switch(config-if)#no switchport
C. switch(config-if)#switchport layer-2
D. switch(config-if)#switchport
|
| Answer: | D. switch(config-if)#switchport
|
| Explanation: | In order to return a switchport back to be a layer 2 port we use the switchport interface configuration command. |
|
| Question: | How do we configure a Catalyst 3550 interface to provide Layer 3 functionality?
A. switch(config)#interface type mod/num
switch(config-if)#ip address ip address mask
B. switch(config)#interface type mod/num
switch(config-if)#switchport mode layer3
switch(config-if)#ip address ip address mask
C. switch(config)#interface type mod/num
switch(config-if)#switchport access ip
switch(config-if)#ip address ip address mask
D. switch(config)#interface type mod/num
switch(config-if)#no switchport
switch(config-if)#ip address ip address mask
|
| Answer: | D. switch(config)#interface type mod/num
switch(config-if)#no switchport
switch(config-if)#ip address ip address mask
|
| Explanation: | After specifying the correct interface we use the no switchport interface configuration command to remove Layer 2 functionality and then assign an IP Address with the ip address ip_address mask interface configuration command. |
|
| Question: | Mulitlayer switching consists of which two parts?
A. Switching engine
B. Route processor
C. Routing engine
D. SVI
|
| Answer: | A. Switching engine
B. Route processor
|
| Explanation: | Multilayer switching uses a switching engine and route processor to perform the basics of route once, switch many. |
|
| Question: | Which are conditions that can cause a packet to be marked as "CEF Punt"?
A. Encapsulation type is not supported.
B. IP TTL is less then 10.
C. MTU is exceeded and there is need for fragmentation.
D. More then one entry to the destination in the FIB Table
|
| Answer: | A. Encapsulation type is not supported.
C. MTU is exceeded and there is need for fragmentation.
|
| Explanation: | none |
|
| Question: | What is the portion of the FIB table called that contains the Layer 2 information for the next-hop?
A. CAM
B. TCAM
C. MAC table
D. Adjacency table
|
| Answer: | D. Adjacency table
|
| Explanation: | The portion of the FIB that contains the Layer 2 information about the next-hop is called the adjacency table. |
|
| Question: | When the FIB table is replicated across any number of independent Layer 3 forwarding engines, we are using ____________.
A. Distributed CEF
B. Accelerated CEF
C. Expedited CEF
D. Assured CEF
|
| Answer: | A. Distributed CEF
|
| Explanation: | When the FIB table is replicated across any number of independent Layer 3 forwarding engines, we are using distributed CEF. |
|
| Question: | When the FIB entry is the CEF Glean state waiting for an ARP response, subsequent packets to that host are dropped so there is no need for duplicate ARP requests. This is called?
A. ARP discarding
B. ARP limiting
C. ARP queueing
D. ARP throttling
|
| Answer: | D. ARP throttling
|
| Explanation: | When the FIB entry is the CEF Glean state waiting for an ARP response, subsequent packets to that host are dropped so there is no need for duplicate ARP requests, this is called ARP throttling or throttling adjacency. |
|
| Question: | How do we assign an IP Address to a SVI?
A. switch(config)#interface vlan vlan_id switch(config-vlan)#ip address ip address mask
B. switch(config)#interface svi type mod/num switch(config-if)#ip address ip address mask
C. switch(config)#interface vlan vlan_id switch(config-if-svi)#ip address ip address mask
D. switch(config)#interface vlan vlan_id switch(config-if)#ip address ip address mask
|
| Answer: | D. switch(config)#interface vlan vlan_id switch(config-if)#ip address ip address mask
|
| Explanation: | Because a SVI, switched virtual interface, can represent an entire VLAN we assign the IP address to the logical VLAN interface. |
|
| Question: | What is the CEF Glean state?
A. When a packet arrives and the next-hop address has an ARP entry in the adjacency table that packet is said to be in CEF Glean state.
B. When further processing is needed by the Layer 3 engine, like fragment the packet, compress the packet,...
C. An ARP entry was not found in the adjacency table, then the packet is sent to the Layer 3 engine so an ARP request can be generated.
D. An IP entry was not found in the adjacency table, then the packet is sent to the Layer 3 engine so an ARP request can be generated.
|
| Answer: | C. An ARP entry was not found in the adjacency table, then the packet is sent to the Layer 3 engine so an ARP request can be generated.
|
| Explanation: | When an ARP entry was not found in the adjacency table, then the packet is sent to the Layer 3 engine so an ARP request can be generated, this is known as the CEF Glean state. |
|
| Question: | On a Catalyst 3550 how do we enable CEF?
A. switch(config)#cef enable
B. switch(config0#ip cef
C. switch(config)#mls cef
D. CEF is enabled by default
|
| Answer: | D. CEF is enabled by default
|
| Explanation: | On Catalyst 3550, 4500 and 6500 (with a Supervisor 720) CEF is enabled by default and can never be disabled. |
|
| Question: | What can we configure on a switch for protocols that cannot be switched or routed by CEF, eg IPX, LAT?
A. Fallback bridging
B. Integrated Routing & Bridging
C. Router-on-a-stick
D. Translational bridging
|
| Answer: | A. Fallback bridging
|
| Explanation: | We can configure fallback bridging for protocols that cannot be routed or switched by CEF, some examples of protocols are AppleTalk, IPX, SNA, LAT,.. |
|
| Question: | How do we configure fallback bridging?
A. switch(config)#bridge-group bridge-group protocol vlan-bridge
B. switch(config)#bridge-group bridge-group vlan-bridge
C. switch(config-vlan)#bridge-group bridge-group protocol protocol_name
D. switch(config)#bridge-group bridge-group protocol protocol_name
|
| Answer: | A. switch(config)#bridge-group bridge-group protocol vlan-bridge
|
| Explanation: | The first step is to enable fallback bridging using the bridge-group bridge-group protocol vlan-bridge global configuration command. We then use the bridge-group bridge-group interface configuration command underneath the VLAN SVI where the nonroutable traffic will be bridged. |
|
| Question: | What is the maximum amount of fallback bridgegroups you can configure on a switch?
A. 8
B. 1
C. 16
D. 32
E. 64
F. 128
G. 31
|
| Answer: | G. 31
|
| Explanation: | You can configure up to 31 bridgegroups on a switch. |
|
| Question: | How can we verify the configuration of a SVI?
A. show interface type mod/num switchport
B. show interface summary
C. show interface svi
D. show interface vlan vlan_id
|
| Answer: | D. show interface vlan vlan_id
|
| Explanation: | To verify the configuration of a SVI interface we use the show interface vlan vlan_id command. |
|
| Question: | How do we show the entire FIB?
A. show ip cef
B. show cef
C. show cef fib
D. show cef detail
|
| Answer: | A. show ip cef
|
| Explanation: | To view the entire FIB we use the show ip cef command. |
|
| Question: | When issueing the show cef not-cef-switched counters are shown for CEF Punt packets. Which of the following are not valide counters
A. Access-List
B. Send
C. Encap
D. Redirect
E. Options
F. Receive
G. No_adj
|
| Answer: | A. Access-List
B. Send
C. Encap
|
| Explanation: | The counters for the CEF punts are:
- No_adj
- No_encap
- Unsuppted
- Redirect
- Receive
- Option
- Accecss
- Frag |
|
| Question: | How can we verify the STP state of the active fallback bridge groups?
A. show bridge group summary
B. show bridge group
C. show bridge group stp
D. show bridge group detail
|
| Answer: | B. show bridge group
|
| Explanation: | The show bridge group command will display a summary of all active fallback bridge groups and their STP states. |
|
| Question: | In an HSRP group a router can be in what states?
A. standby
B. listen
C. active
D. backup
E. learning
F. passive
|
| Answer: | A. standby
B. listen
C. active
|
| Explanation: | In a HSRP group is elected to be the primary or active router, a standby router is also elected. The remaining routers remain in listen state. |
|
| Question: | How do we set the HSRP priority?
A. switch(config-if)#standby group priority priority
B. switch(config-if)#standby priority priority
C. switch(config)#standby group priority priority
D. switch(config-if)#standby priority group priority
|
| Answer: | A. switch(config-if)#standby group priority priority
|
| Explanation: | To set the HSRP priority we use the standby group priority priority interface configuration command. |
|
| Question: | How can we configure a router to immediately take over the active role if its priority is higher?
A. switch(config-if)#standby group active
B. switch(config-if)#standby-priority group high
C. switch(config-if)#standby group preempt
D. switch(config)#standby group preempt
E. switch(config)#standby group active
|
| Answer: | C. switch(config-if)#standby group preempt
|
| Explanation: | We use the standby group preempt interface configuration command if we want the switch to take the active role when its priority is the highest at any time. |
|
| Question: | What can we configure the switch to make the HSRP group more secure?
A. switch(config-if)#standby group authentication string
B. switch(config-if)#standby group authentication md5 string
C. switch(config-if)#standby group md5-authentication string
D. switch(config)#standby group authentication string
E. switch(config)#stanby group authentication md5 string
|
| Answer: | A. switch(config-if)#standby group authentication string
|
| Explanation: | We can use the standby group authentication string interface configuration command to add clear text authentication to the group to prevent devices with a default configuration to participate. |
|
| Question: | The default hello timer of HSRP is?
A. 10 seconds
B. 5 seconds
C. 3 seconds
D. 2 seconds
|
| Answer: | C. 3 seconds
|
| Explanation: | By default hello messages are sent every 3 seconds. |
|
| Question: | What is the virtual MAC address generated by HSRP?
A. 0000.0c07.acxx where xx is the HSRP group nr represented in hex
B. 0000.5e00.01xx where xx is the HSRP group nr represented in hex
C. C000.abcd.acxx where xx is the HSRP group nr represented in hex
D. C000.0c07.acxx where xx is the HSRP group nr represented in hex
|
| Answer: | A. 0000.0c07.acxx where xx is the HSRP group nr represented in hex
|
| Explanation: | The virtual MAC address generated by HSRP is 0000.0c07.acxx where xx is the HSRP group nr represented in hex. |
|
| Question: | The default VRRP priority is?
A. 100
B. 254
C. 255
D. 1
E. 0
|
| Answer: | A. 100
|
| Explanation: | The default router priority in VRRP is 100. |
|
| Question: | VRRP-advertisments are sent by default every __________ seconds.
A. 5
B. 10
C. 20
D. 30
E. 2
F. 1
|
| Answer: | F. 1
|
| Explanation: | By default, VRRP-advertisments are sent every second. |
|
| Question: | What could cause a router to be elected as the Active Virtual Gateway?
A. Highest priority
B. Highest IP Address
C. Lowest IP Address
D. Highest MAC Address
E. Lowest MAC Address
|
| Answer: | A. Highest priority
B. Highest IP Address
|
| Explanation: | The Active Virtual Gateway is the router that has the highest priority or the highest IP Address. |
|
| Question: | Which of the following are GLBP load-balancing methods?
A. Weighted
B. Network-dependent
C. Host-dependent
D. Weighted round robin
E. Round Robin
F. Weighted Random Early Detection
|
| Answer: | A. Weighted
C. Host-dependent
E. Round Robin
|
| Explanation: | GLBP, Gateway Load Balancing Protocol can use following load-balancing methods:
- Round robin
- Weighted
- Host-dependent |
|
| Question: | Which of the following are SLB load-balancing methods?
A. Weighted
B. Host-dependent
C. Round robin
D. Weighted round robin
E. Weighted least connection
|
| Answer: | D. Weighted round robin
E. Weighted least connection
|
| Explanation: | SLB, Server Load Balancing, can use the following load-balancing methods:
- weighted round robin
- weighted least connection |
|
| Question: | How do we configure the load-balancing method that SLB uses?
A. switch(config)#predictor {roundrobin | leastconns}
B. switch(config-slb-vserver)#predictor {roundrobin | leastconns}
C. switch(config-slb)#predictor {roundrobin | leastconns}
D. switch(config-slb-sfarm)#predictor {roundrobin | leastconns}
|
| Answer: | D. switch(config-slb-sfarm)#predictor {roundrobin | leastconns}
|
| Explanation: | After configuring a server farm we use the predictor {roundrobin | leastconns} configuration command to set the load-balancing method. This is done underneath the server farm configuration. |
|
| Question: | How can we check the status of HSRP?
A. show ip hsrp status
B. show hspr status
C. show standby brief
D. show ip hsrp detail
|
| Answer: | C. show standby brief
|
| Explanation: | The show standby brief command will display the status of HSRP. |
|
| Question: | What is the range of adminstratively scoped addresses?
A. 239.0.0.0 - 239.255.255.255
B. 224.0.0.0 - 239.255.255.255
C. 224.0.1.0 - 238.255.255.255
D. 224.0.0.0 - 224.0.0.255
|
| Answer: | A. 239.0.0.0 - 239.255.255.255
|
| Explanation: | complete multicast space: 224.0.0.0 - 239.255.255.255
link-local addresses: 224.0.0.0 - 224.0.0.255
administratively scoped: 239.0.0.0 - 239.255.255.255
globally scoped: 224.0.1.0 - 238.255.255.255 |
|
| Question: | What can we use to make sure that packets are not injected back into the tree?
A. Reverse Path Forwarding
B. Split Horizon
C. Split Horizon with Poison Reverse
D. Apply access-lists
|
| Answer: | A. Reverse Path Forwarding
|
| Explanation: | Reverse Path Forwarding is a means to make sure packets are not being injected back into the tree at an unexpected location. |
|
| Question: | IGMPv2 uses which multicast address to send a Leave Group message?
A. 224.0.0.1
B. 224.0.0.5
C. 224.0.0.16
D. 224.0.0.2
|
| Answer: | D. 224.0.0.2
|
| Explanation: | A Leave Group message is sent to the all-routers multicast address of 224.0.0.2 |
|
| Question: | In IGMPv1 queries are sent every ________ seconds.
A. 10
B. 30
C. 90
D. 180
E. 60
|
| Answer: | E. 60
|
| Explanation: | IGMPv1 sends out queries every 60 seconds to see if there are still hosts interested in receving the multicast on a specific segment. |
|
| Question: | In PIM Sparse mode the root router is called?
A. Rendezvous Point
B. Root
C. Master
D. Reference Point
|
| Answer: | A. Rendezvous Point
|
| Explanation: | In PIM Sparse mode the root router is called the Rendezvous Point. |
|
| Question: | How do we configure PIM Dense Mode?
A. switch(config-if)#pim dense-mode
B. switch(config-if)#pim mode dense
C. switch(config-if)#no ip pim mode sparse
D. switch(config-if)#ip pim dense-mode
E. switch(config-if)#ip pim mode dense
|
| Answer: | D. switch(config-if)#ip pim dense-mode
|
| Explanation: | To configure PIM dense mode we use the ip pim dense-mode interface configuration command. |
|
| Question: | How do we configure a mapping agent?
A. switch(config)#ip pim send-rp-discovery scope ttl
B. switch(config-if)#ip pim send-rp-discovery scope ttl
C. switch(config-if)#ip pim send-discovery scope ttl
D. switch(config)#ip pim send-rp-discovery
|
| Answer: | A. switch(config)#ip pim send-rp-discovery scope ttl
|
| Explanation: | To configure a mapping agent we use the ip pim send-rp-discovery scope ttl global configuration command. |
|
| Question: | How do we enable IGMP snooping on a new switch?
A. IGMP snooping is enabled by default
B. switch(config)#no ip cgmp
C. switch(config)#ip igmp snooping
D. switch(config-if)#ip igmp snooping
|
| Answer: | A. IGMP snooping is enabled by default
|
| Explanation: | On switch platforms that support IGMP snooping, IGMP is enabled by default. |
|
| Question: | In PIMv2, what is the dynamic RP-to-group mapping called?
A. auto-rp method
B. dynamic-rp method
C. rendezvous point method
D. bootstrap router method
|
| Answer: | D. bootstrap router method
|
| Explanation: | The bootstrap router method is used by PIMv2 to dynamically map RP-to-groups. |
|
| Question: | Which IETF standard defines inline power?
A. 802.3b
B. 802.3af
C. 802.3de
D. 802.5
|
| Answer: | B. 802.3af
|
| Explanation: | The IETF standard 802.3af defines inline power. |
|
| Question: | What is the voltage that an IP Phone uses and can be provided via inline power or external adapter?
A. 12V AC
B. 12V DC
C. 48V DC
D. 48V AC
E. 24V DC
F. 24V AC
|
| Answer: | C. 48V DC
|
| Explanation: | IP Phones use 48V DC. |
|
| Question: | Inline power is provided over which pairs of a Cat5 wiring?
A. pair 1
B. pair 4
C. pair 2
D. pair 3
|
| Answer: | C. pair 2
D. pair 3
|
| Explanation: | Inline power use pairs 2 and 3, RJ-45 pin 1,2 and 3,6. |
|
| Question: | How do we configure a voice VLAN?
A. switch(config-if)#voice vlan vlan_id
B. switch(config-vlan)#voice vlan vlan_id
C. switch(config-if)#switchport voice vlan vlan_id
D. switch(config)#voice vlan vlan_id
|
| Answer: | C. switch(config-if)#switchport voice vlan vlan_id
|
| Explanation: | To configure a voice vlan we use the voice vlan {vlan_id | dot1q | untagged | none} interface configuration command. |
|
| Question: | When using the untagged keyword in the voice vlan configuration, voice packets are placed into which vlan?
A. vlan 1
B. vlan specified in the configuration
C. vlan 0
D. native vlan
|
| Answer: | D. native vlan
|
| Explanation: | When using the untagged keyword in the voice vlan configuration, voice packets are placed into vlan 0. |
|
| Question: | The Skinny Gateway Protocol uses which tcp port?
A. 2001
B. 2003
C. 2000
D. 2002
|
| Answer: | D. 2002
|
| Explanation: | Skinny Gateway Protocol uses TCP port 2002. |
|
| Question: | RTP voice packets receive which CoS value from an IP Phone?
A. 3
B. 1
C. 2
D. 4
E. 5
|
| Answer: | E. 5
|
| Explanation: | RTP voice bearer packets receive CoS value 5, IP Presedence 5 and DSCP 46 (EF) according to the QoS rules of a Cisco IP Phone. |
|
| Question: | How can we verify the inline power for a switch port?
A. show inline-power
B. show ip inline-power
C. show power inline
D. show ip power-inline
|
| Answer: | C. show power inline
|
| Explanation: | We use the show power inline command to verify the inline power of a switchport. |
|
| Question: | How do we instruct an IP Phone to extend the QoS trust to its own switchport?
A. switch(config-if)#switchport extend trust
B. switch(config-if)#switchport priority extend trust
C. switch(config-if)#switchport qos extend trus
D. switch(config-if)#switchport mls qos extend trust
|
| Answer: | B. switch(config-if)#switchport priority extend trust
|
| Explanation: | To instruct an IP Phone to extend the QoS trust to its own switchport we use the switchport priority extend {cos value | trust} interface configuration command. |
|
| Question: | TCP port 2001 is used by which protocol?
A. Skinny Voice Protocol
B. Skinny Station Protocol
C. Skinny Client Control Protocol
D. Skinny Gateway Protocol
|
| Answer: | B. Skinny Station Protocol
|
| Explanation: | Skinny Station Protocol used TCP port 2001. |
|
| Question: | A multicast MAC address always starts with?
A. 0000.5e
B. 0100.5e
C. C000.5e
D. 1000.5e
|
| Answer: | B. 0100.5e
|
| Explanation: | A multicast MAC address always starts with 0100.5e |
|
| Question: | How do manually assign a RP in PIMv1?
A. switch(config-if)#ip pim rp-address ip_address
B. switch(config)#ip pim rendezvouspoint-address ip_address
C. switch(config)#ip pim rp-address ip_address
D. switch(config)#ip pim version1 rp-address ip_address
|
| Answer: | C. switch(config)#ip pim rp-address ip_address
|
| Explanation: | To manually assign a Rendezvous point we use the ip pim rp-address ip_address global configuration command. |
|
| Question: | How do we enable authentication, authorization and accounting on a switch?
A. switch(config-aaa)#name name
B. switch(config)#aaa new-model enable
C. switch(config)#aaa new-model
D. switch(config)#aaa enable
|
| Answer: | C. switch(config)#aaa new-model
|
| Explanation: | To enable AAA we use the aaa new-model global configuration command. |
|
| Question: | What is the multicast MAC address of the following 224.0.10.15?
A. 0100.5e00.0a0f
B. 0100.5e00.0b0f
C. 0100.5e00.0a0d
D. 0100.5e00.0b0d
|
| Answer: | A. 0100.5e00.0a0f
|
| Explanation: | Multicast MAC addresses are formed using the 0100.5exx.xxx ethernet address where xx.xxxx are the lower 23 bits of the IP Address.
If we apply that theory here we end up with the following:
224.0.10.15 in binary
11100000.00000000.00001010.00001111
We convert the last 23 bits to hex
0.0.0a.0f
Giving us an ethernet MAC address of 0100.5e00.0a0f |
|
| Question: | How do we configure the use of Tacacs+ authentication?
A. switch(config)#authentication login tacacs+
B. switch(config)#aaa login tacacs+
C. switch(config)#aaa authentication login tacacs+
D. switch(config-aaa)#authentication login tacacs+
|
| Answer: | C. switch(config)#aaa authentication login tacacs+
|
| Explanation: | To use Tacacs+ authentication we use the aaa authentication login tacacs+ global configuration command. |
|
| Question: | How do we create a user database on the switch?
A. switch(config)#username name password password
B. switch(config-aaa)#username name password password
C. switch(config-database)#username name password password
D. switch(config-line)#username name password password
|
| Answer: | A. switch(config)#username name password password
|
| Explanation: | To create a user database on a switch we use the username name password password global configuration command for each user that needs access to the switch. |
|
| Question: | We want to make sure that a user is allowed to use configuration commands. How do we achieve this?
A. switch(config)#aaa authorization config-commands
B. switch(config)#aaa authorization commands
C. switch(config)#aaa authorization config-commands allow
D. switch(config)#aaa authorization config-commands enable
|
| Answer: | A. switch(config)#aaa authorization config-commands
|
| Explanation: | We can use the aaa authorization config-commands to make sure a user is authorized to use configuration commands. |
|
| Question: | How can we record, using aaa, reloads of a device?
A. switch(config)#aaa accounting system
B. switch(config)#aaa accounting reload
C. switch(config)#aaa accounting events
D. switch(config)#aaa accounting exec
|
| Answer: | A. switch(config)#aaa accounting system
|
| Explanation: | To record reload we use the aaa accounting system global configuration command. |
|
| Question: | We want to shutdown the switchport when a MAC address is discovered on that port that is not allowed. How do we achieve this?
A. switch(config-if)#switchport port-security shutdown
B. switch(config-if)#switchport port-security errdisable shutdown
C. switch(config-if)#switchport port-security violation shutdown
D. switch(config-if)#switchport violation shutdown
|
| Answer: | C. switch(config-if)#switchport port-security violation shutdown
|
| Explanation: | In order to shutdown a switchport when a MAC address is discovered that is not allowed to be on that port we use the switchport port-security violation shutdown interface configuration command. |
|
| Question: | When using the port-security violation command, which conditions can we set?
A. reverse-access
B. system
C. shutdown
D. protect
E. disable
F. timed
G. restrict
|
| Answer: | C. shutdown
D. protect
G. restrict
|
| Explanation: | We can use the following keywords with the switchport port-security violation interface configuration command:
- shutdown, the port is put into errdisable state
- restrict, the port is allowed to stay up but packets from violating MAC addresses are dropped and a SNMP trap can be send
- protect, same as restrict but no record of the violation is kept |
|
| Question: | In order to use port-based authentication the switch and the end-user PC must support which protocol?
A. WEP
B. AAA
C. EAPOL
D. EAP
|
| Answer: | C. EAPOL
|
| Explanation: | In order to use port-based authentication the switch and the end-user PC must support EAPOL, Extensible Authentication Protocol over LANs. |
|
| Question: | How do we enable 802.1x on a switch?
A. switch(config)#dot1x system-auth-control
B. switch(config)#system-auth-control 8021x
C. switch(config)#aaa dot1x authentication
D. switch(config)#dot1x authentication
|
| Answer: | A. switch(config)#dot1x system-auth-control
|
| Explanation: | We use the dot1x system-auth-control global configuration command to enable 802.1x on a switch. |
|
| Question: | What is the first step in configuring a VACL?
A. switch(config)#vlan access-map map_name
B. switch(config-vlan)#access-map map_name
C. switch(config-vlan)#vlan access-map map_name
D. switch(config-if)#vlan access-map map_name
|
| Answer: | A. switch(config)#vlan access-map map_name
|
| Explanation: | We first define the VACL using the vlan access-map map_name global configuration command. |
|
| Question: | Which of the following are actions that can be done by a VACL?
A. drop
B. allow
C. forward
D. set QoS/CoS value
E. redirect
F. block
|
| Answer: | A. drop
C. forward
E. redirect
|
| Explanation: | A VACL can either drop a matching packet, forward it or redirect it to another interface. |
|
| Question: | When using a Private VLAN a secondary VLAN can be configured as?
A. Public
B. Promiscuous
C. Secondary
D. Isolated
E. Community
|
| Answer: | D. Isolated
E. Community
|
| Explanation: | When using a Private VLAN a secondary VLAN can be configured as one of the following:
- Isolated
- Community |
|
| Question: | How do we associate the primary VLAN to all of the component secondary VLANs?
A. switch(config-vlan)#primary-vlan association secondary-vlan-list
B. switch(config-vlan)#secondary-vlan association primary-vlan-list
C. switch(config-vlan)#private-vlan association primary-vlan-list
D. switch(config-vlan)#private-vlan association secondary-vlan-list
|
| Answer: | D. switch(config-vlan)#private-vlan association secondary-vlan-list
|
| Explanation: | in order to associate the primary VLAN to all of the component secondary VLANs we use the private-vlan association secondary-vlan-list vlan configuration command. |
|
| Question: | Which of the following are methods of switch port monitoring?
A. Remote SPAN
B. Host SPAN
C. VLAN SPAN
D. Distributed SPAN
E. Local SPAN
|
| Answer: | A. Remote SPAN
C. VLAN SPAN
E. Local SPAN
|
| Explanation: | We can use one of the following methods to do switch port monitoring:
- Local SPAN
- VLAN SPAN or VSPAN
- Remote SPAN |
|
| Question: | How do we display the active SPAN sessions?
A. show monitor
B. show span
C. show span active
D. show span detail
|
| Answer: | A. show monitor
|
| Explanation: | The show monitor command will display the active SPAN sessions. |
|
| Question: | EIGRP uses what algorithm to determine path selection?
A. Diffusing update algorithm
B. Bellman Ford
C. Dijkstra
D. Diffie-Hellman
|
| Answer: | A. Diffusing update algorithm
|
| Explanation: | EIGRP uses DUAL or Diffusing Update Algorithm to make path selections. |
|
| Question: | Which of the following requirements have to be fulfilled in order to create a virtual link?
A. The transit area can be a stub area
B. The transit area can not be a stub area
C. The transit area can be a not-so-stubby area
D. The tranist area needs to have full routing information
E. The virtual link can be terminated on an interior router
|
| Answer: | B. The transit area can not be a stub area
D. The tranist area needs to have full routing information
|
| Explanation: | The area through which you configure the virtual link, known as a transit area, must have full routing information and this transit area cannot be a stub area. Virtual links are configured between ABRs and one of them must have a connection to the backbone. |
|
| Question: | How can we change the default cost to the default route that is advertised into a stub area?
A. R1(config-router)#area x default-cost value
B. R1(config-router)#area x cost value
C. R1(config-if)#area x default-cost value
D. R1(config-if)#ip ospf default-cost value
|
| Answer: | A. R1(config-router)#area x default-cost value
|
| Explanation: | To define the cost of the default route generated and advertised by the ABR to the stub area we use the area area_id default-cost cost router configuration command. |
|
| Question: | In a NSSA which type of LSAs are not propgated into that area?
A. LSA type 1
B. LSA type 5
C. LSA type 7
D. LSA type 2
E. LSA type 4
F. LSA type 3
|
| Answer: | B. LSA type 5
E. LSA type 4
|
| Explanation: | In a NSSA (not-so-stubby area) there are no LSA type 4 and 5 propagated into or out of the area. |
|
| Question: | How do we define the source for Local SPAN?
A. switch(config)#monitor session session source interface type mod/num both
B. switch(config)#monitor span source interface type mod/num both
C. switch(config)#monitor-span session session source interface type mod/num both
D. switch(config)#span session session source interface type mod/num both
|
| Answer: | A. switch(config)#monitor session session source interface type mod/num both
|
| Explanation: | The first step we do when configuring a SPAN session is define the source. We use the monitor session session source {interface type mod/num | vlan vlan_id} [rx | tx | both] global configuration command to define that required source. |
|
| Question: | If a route in the routing table is marked as O E1 we know the following about that route:
A. An LSA type 5 external link in which only the cost of path from the ASBR to the next-hop router outside the AS is considered.
B. An LSA type 4 external link in which only the cost of path from the ASBR to the next-hop router outside the AS is considered.
C. An LSA type 4 summary link in which the cost of the path to the ASBR is added to the external cost to reach the next-hop router outside the AS.
D. An LSA type 5 summary link in which the cost of the path to the ASBR is added to the external cost to reach the next-hop router outside the AS.
E. An LSA type 3 external link in which only the cost of path from the ASBR to the next-hop router outside the AS is considered.
F. An LSA type 5 external link in which the cost of the path to the ASBR is added to the external cost to reach the next-hop router outside the AS.
G. An LSA type 3 summary link in which the cost of the path to the ASBR is added to the external cost to reach the next-hop router outside the AS.
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| Answer: | F. An LSA type 5 external link in which the cost of the path to the ASBR is added to the external cost to reach the next-hop router outside the AS.
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| Explanation: | If the routing table entry is marked with O E1 it means that the LSA type 5 external route added the cost of the path to the ASBR to the external cost to reach the next-hop router outside the AS. |
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| Question: | Which command would produce the following output?
Internet Address 172.16.2.2, Mask 255.255.255.0, Area 0.0.0.0
AS 1, Router ID 192.168.99.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State OTHER, Priority 1
Designated Router id 192.168.25.1, Interface address 192.168.25.1
Backup Designated router id 192.168.4.8, Interface addr 192.168.4.8
Timer intervals configured, Hello 10, Dead 60, Wait 40, Retransmit 5
Hello due in 0:00:05
Neighbor Count is 8, Adjacent neighbor count is 2
Adjacent with neighbor 192.168.4.8 (Backup Designated Router)
Adjacent with neighbor 192.168.25.1 (Designated Router)
A. show ip ospf
B. show ip ospf border-routers
C. show ip ospf interface
D. show ip ospf database
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| Answer: | C. show ip ospf interface
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| Explanation: | R1# show ip ospf interface ethernet 0
Ethernet 0 is up, line protocol is up
Internet Address 172.16.2.2, Mask 255.255.255.0, Area 0.0.0.0
AS 1, Router ID 192.168.99.1, Network Type BROADCAST, Cost: 10
Transmit Delay is 1 sec, State OTHER, Priority 1
Designated Router id 192.168.25.1, Interface address 192.168.25.1
Backup Designated router id 192.168.4.8, Interface addr 192.168.4.8
Timer intervals configured, Hello 10, Dead 60, Wait 40, Retransmit 5
Hello due in 0:00:05
Neighbor Count is 8, Adjacent neighbor count is 2
Adjacent with neighbor 192.168.4.8 (Backup Designated Router)
Adjacent with neighbor 192.168.25.1 (Designated Router)
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| Question: | On what type of router do we configure the summary address in OSPF?
A. Interior
B. ASBR
C. ABR
D. Backbone
|
| Answer: | B. ASBR
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| Explanation: | The summary address is used to summarize the networks that will be advertised to the outside world. This is configured on the ASBR. |
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| Question: | Following Ciscos design recommendations for OSPF what is the maximum amount of routers in an area?
A. 250
B. unlimited
C. 50
D. 25
E. 100
|
| Answer: | C. 50
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| Explanation: | Ciscos design recommendations for OSPF stipulate the following:
- routers per area: 50
- neighbors per router: 60
- areas per router: 3
- a router may not be a DR or BDR for more then 1 LAN |
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| Question: | What could prevent OSPF adjacencies to be formed?
A. misconfigured hello timer
B. misconfigured MTU
C. no loopback interfaces configured
D. misconfigured bandwidth statement
E. misconfigured ospf priority
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| Answer: | A. misconfigured hello timer
B. misconfigured MTU
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| Explanation: | Some common problems for adjacencies not being formed are misconfigured IP mask, MTU, interface hello timer, OSPF hello interval and OSPF dead interval. Also make sure that both neighbors are part of the same area and area type. |
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| Question: | In the ISO address the area and system id of a system is IS-IS is described in the?
A. Network Selector
B. Host address
C. Subnetwork point of attachment
D. Network Entity Title
|
| Answer: | D. Network Entity Title
|
| Explanation: | The Network Entity Title (NET) describes both the area and system id of a system in the IS-IS network but excludes the Network Selector (NSEL), which defines the Network Service Access Point (NSAP) address of the system. |
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| Question: | In ISO addressing which two fields are used for external routing?
A. Initial domain identifier (IDI)
B. System ID
C. Network selector (NSEL)
D. Authority and format identifier (AFI)
E. High order DSP
|
| Answer: | A. Initial domain identifier (IDI)
D. Authority and format identifier (AFI)
|
| Explanation: | The IDP part of an ISO address is used for external routing and is issued by the ISO. It contains 2 parts, the authority and format identifier (AFI) and the initial domain identifier (IDI). |
|
| Question: | Which statements are true regarding ISO addressing?
A. All level 1 routers must have a system ID that is unique for the entire domain.
B. All level 2 routers must have a system ID that is unique for the entire area.
C. The ISO address is assigned to the interface.
D. All level 2 routers must have a system ID that is unique for the entire domain.
E. All level 1 routers must have a system ID that is unique for the entire area.
F. The area address must be the same for all routers in the same domain.
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| Answer: | D. All level 2 routers must have a system ID that is unique for the entire domain.
E. All level 1 routers must have a system ID that is unique for the entire area.
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| Explanation: | Some of the rules for ISO addressing:
- the ISO address is assigned to the system, not to the interface
- the router has one NET address, with a limit of 3 per area in multiarea Intergrated IS-IS
- when multiple NETs are configured on the same router they must have the same system id
- the area address must be the same for all routers in the same area
- Level 2 routers must have a system ID that is unique for the entire domain
- Level 1 routers must have a system ID that is unique for the entire area
- The system ID length must be the same for ISs and ESs within a routing domain |
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| Question: | Which IS-IS packet is used to request individual LSPs and to acknowledge receipt of those?
A. Level 1 LSP
B. Level 2 LSP
C. LAN Level 1
D. LAN Level 2
E. CSNP
F. PSNP
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| Answer: | F. PSNP
|
| Explanation: | A PSNP or Partial Sequence Number Packet is used to request individual LSPs and to acknowledge receipts of these LSPs. |
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| Question: | When configuring IS-IS on a Cisco router it is which IS-IS router by default?
A. Level 1
B. Level 2
C. No defaults, this needs to be configured.
D. Level 1-2
|
| Answer: | D. Level 1-2
|
| Explanation: | The IS-IS Level 1-2 router configuration is the default configuration on Cisco routers. |
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| Question: | Which of the following are IS-IS network types?
A. Broadcast
B. Point-to-multipoint
C. Point-to-point
D. Point-to-multipoint nonbroadcast
E. NonBroadcast MultiAccess
|
| Answer: | A. Broadcast
C. Point-to-point
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| Explanation: | IS-IS defines 2 network types, broadcast subnetworks and point-to-point networks. |
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| Question: | Which fields in the IS-IS LAN Hello packet are not in the Point-to-Point Hello packet?
A. Holding time
B. LAN ID
C. Local Circuit ID
D. Priority
E. Circuit type
|
| Answer: | B. LAN ID
D. Priority
|
| Explanation: | The common fields in both Hello packets are:
- Fixed Integrated IS-IS header
- Circuit type
- Source ID
- Holding time
- Packet length
In Point-to-point Hello packets we have an additional Local Circuit ID field. In LAN Hello packets there are the Priority and LAN ID fields. |
|
| Question: | TLV code 129 or Protocols Supported are used by which PDU?
A. Hello
B. LSP Level 1
C. LSP Level 2
D. LSP Level 1 and 2
E. SNP
|
| Answer: | A. Hello
|
| Explanation: | TLV code 129, Protocols Supported is used by the Hello PDU and states the protocols that the transmitting router supports, i.e. CLNS only, IP only or both. |
|
| Question: | ISO 10589 defines the metric for Integrated IS-IS. Which of the following are part of that?
A. Bandwidth
B. Error
C. Reliability
D. Hop
E. Delay
F. Attribute
|
| Answer: | B. Error
E. Delay
|
| Explanation: | Integrated IS-IS has 4 metrics defined by ISO 10589:
- Default
- Delay
- Expense
- Error |
|
| Question: | A DIS sends out Hello Packets every __________ seconds?
A. 10
B. 45
C. 3
D. 15
E. 3.3
F. 30
|
| Answer: | E. 3.3
|
| Explanation: | A DIS sends out Hello packets every 3.3 seconds to maintain the adjacencies with the other routers. Other routers send out Hello Packets every 10 seconds. |
|
| Question: | The default BGP holdtime for a session is?
A. 180 seconds
B. 60 seconds
C. 240 seconds
D. 120 seconds
|
| Answer: | A. 180 seconds
|
| Explanation: | The default BGP holdtime, sent in the open message, is 180 seconds. |
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