| Question: | Which of the following are part of the Ternary Content Addressable Memory?
A. Switching Database Manager
B. Filter Manager
C. Forwarding Information Base
D. Feature Manager
E. Routing Database Manager
|
| Answer: | A. Switching Database Manager
D. Feature 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 switch port to be a 802.1Q trunk?
A. S1(config-if)#switchport trunk encapsulation dot1q S1(config-if)#switchport mode trunk
B. S1(config-if)#switchport trunk encapsulation 802.1Q S1(config-if)#switchport mode trunk
C. S1(config-if)#trunk encapsulation dot1q S1(config-if)#switchport mode trunk
D. S1(config-if)#switchport trunk encapsulation dot1q S1(config-if)#switchport mode access
|
| Answer: | A. 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 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 mode trunk allowed vlan 5
D. S1(config-if)#switchport trunk allowed vlan 5
|
| Answer: | D. 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: | 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. The other end is configured as dynamic auto.
C. Only when the other end is configured as trunk.
D. When the other end is configured as nonegotiate.
|
| 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: | How do we configure a 802.1Q tunnel?
A. S1(config-if)#switchport access vlan vlan_id S1(config-if)#switchport mode dot1qtunnel
B. S1(config-if)#switchport mode access vlan vlan_id S1(config-if)#switchport mode tunnel dot1q
C. S1(config-if)#switchport mode tunnel S1(config-if-tunnel)#encapsulation dot1q
D. S1(config-if)#switchport mode tunnel encapsulation dot1q
|
| Answer: | A. S1(config-if)#switchport access vlan vlan_id S1(config-if)#switchport mode dot1qtunnel
|
| Explanation: | The switchport access vlan vlan_id defines the VLAN_ID that will be connected to the physical interface. We then use the switchport mode dot1qtunnel command to make the switch port a tunnel. |
|
| Question: | Which control protocol PDUs are sent over VLAN 1 on a trunk?
A. SLB
B. TPID
C. DSCP
D. GLBP
E. SSP
F. CDP
G. STP
H. VTP
|
| Answer: | F. CDP
G. STP
H. 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 only on the edge 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 on all MPLS routers.
|
| Answer: | A. EoMPLS has to be configured only on the edge routers.
D. The service provider must have a MPLS core network.
|
| 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. STP timers
B. trunking mode
C. trunk speed
D. DTP timers
E. trunk encapsulation
|
| Answer: | B. 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 trunk interface type mod/num trunk
B. show trunk
C. show trunk vlan
D. show interface trunk
E. show interface type mod/num trunk
|
| Answer: | E. 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. Client
B. Transparent
C. Server
D. Master
E. Transitional
F. Native
G. Slave
|
| Answer: | D. Master
E. Transitional
F. Native
G. Slave
|
| Explanation: | VTP has 3 modes:
- Server
- Client
- Transparent |
|
| Question: | In which VTP mode can you create locally significant VLANs?
A. Transparent
B. Client
C. Native
D. Server
|
| Answer: | A. 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. Change the switch to client mode then change it back to server mode.
B. Change the switchs VTP domain name and then change it back to the original VTP domain name.
C. By using the clear vtp command.
D. Change the switch to transparent mode then change it back to server mode.
E. By using the clear vtp counters command.
|
| Answer: | B. Change the switchs VTP domain name and then change it back to the original VTP domain name.
D. Change the switch to transparent mode then change it back to server mode.
|
| 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. Advertisment requests from transparent
B. Update advertisments
C. Keepalive advertisments
D. Synchronization advertisments
E. Subset advertisments
F. Advertisment requests from clients
G. Summary advertisments
|
| Answer: | E. Subset advertisments
F. Advertisment requests from clients
G. Summary 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: | C. 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 summary
B. show vtp status
C. show vtp advertisments
D. show vtp counters
|
| Answer: | D. 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)#switchport trunk pruning vlan except 5
B. S1(config)#switchport trunk pruning vlan remove 5
C. S1(config-if)#switchport mode trunk pruning vlan except 5
D. S1(config-if)#switchport trunk pruning vlan remove 5
E. S1(config-if)#switchport mode trunk pruning vlan remove 5
F. S1(config-if)#switchport trunk pruning vlan except 5
|
| Answer: | F. 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 bundled ports have to be in the same VLAN.
B. When trunks are used they must pass the same VLANs.
C. Duplex settings have to be identical but speed settings can vary.
D. All ports in the EtherChannel have to be trunks.
E. When trunks are used they can carry different VLANs.
|
| Answer: | A. All bundled ports have to be in the same VLAN.
B. 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. PAgP
B. LACP
C. DTP
D. DSCP
E. IGMP
F. NBAR
|
| Answer: | A. PAgP
B. 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: | In LACP the system priority is made up of?
A. 2-byte port number
B. 6-byte priority value
C. 2-bit priority value
D. 2-byte priority value
E. 6-byte switch MAC Address
F. 4-byte priority value
G. 4-byte switch value
|
| Answer: | D. 2-byte priority value
E. 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 port
D. show etherchannel interface
|
| Answer: | C. 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
B. show lacp system-id
C. show lacp
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. Configuration BPDU
B. Hello BPDU
C. Topology Change Notification BPDU
D. Configuration Change Notification BPDU
E. Topology Control BPDU
|
| Answer: | A. Configuration BPDU
C. Topology Change Notification 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. Classification
C. Scheduling
D. Policing
|
| 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)#enable qos
B. no configuration needed, qos is enabled by default
C. switch(config)#mls qos
D. switch(config)#qos enable
|
| Answer: | C. switch(config)#mls qos
|
| Explanation: | The mls qos global configuration command will enable QoS on a switch. |
|
| Question: | When enabling the UplinkFast feature what will be done on the switch?
A. The bridge priority is raised to 49152.
B. The bridge priority is lowered to 32767.
C. The port cost is increased by 3000.
D. The port cost is increased to 3000.
|
| Answer: | A. The bridge priority is raised to 49152.
C. 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. Root Discovery Protocol
B. Root Link Query
C. BPDUs
D. Discovery Protocol
|
| Answer: | B. 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. the root bridge
B. the core switches only
C. every switch in the network
D. nowhere, it is enabled by default
|
| Answer: | C. 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 summary
B. show spanning-tree port
C. show spanning-tree brief
D. show spanning-tree
|
| Answer: | C. 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 summary
B. show spanning-tree ports detail
C. show spanning-tree brief
D. show spanning-tree port
|
| Answer: | A. 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 is not running spanning tree.
B. A port that neither the root or designated port.
C. A port that has a normal end user connection.
D. A port that is administratively shutdown.
|
| Answer: | B. 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 root guard enable
B. switch(config-if)#spanning-tree guard root
C. switch(config-if)#spanning-tree rootguard
D. switch(config-if)#spanning-tree root guard
|
| Answer: | B. 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 only be able to receive BPDUs and not forward them.
B. A port will always become the root port.
C. A port will only be able to relay BPDUs not receive them.
D. A port will always become a designated port.
|
| Answer: | C. 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: | How do we enable BPDU Guard on a single interface?
A. switch(config)#spanning-tree bpduguard enable
B. switch(config-if)#spanning-tree bpduguard
C. switch(config-if)#spanning-tree bpduguard enable
D. switch(config)#spanning-tree bpduguard
E. switch(config-if)#bpduguard enable
|
| Answer: | C. switch(config-if)#spanning-tree bpduguard enable
|
| Explanation: | To enable BPDU Guard we use the spanning-tree bpduguard enable interface configuration command. |
|
| 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. Loop Guard
B. Rapid Spanning Tree
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. Root Guard
B. Loop Guard
C. BPDU Guard
D. Link Guard
|
| Answer: | B. 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. 7 seconds
B. 90 seconds
C. 20 seconds
D. 15 seconds
E. 10 seconds
F. 2 seconds
G. 30 seconds
|
| Answer: | A. 7 seconds
B. 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. Normal
B. Quiet
C. Aggressive
D. Silent
E. Desirable
|
| Answer: | A. Normal
C. Aggressive
|
| Explanation: | The two modes of UDLD operation are:
- Normal
- Aggressive |
|
| Question: | If UDLD places a port in errdisable state, UDLD is operating in which mode?
A. Quick
B. Silent
C. Aggressive
D. Error Detection
|
| Answer: | C. Aggressive
|
| Explanation: | When UDLD puts the port in errdisable state UDLD is operating in aggressive mode. |
|
| Question: | How do we enable UDLD in normal mode on our fibre optic switch (ie all ports are fibre optic)?
A. switch(config)#udld mode normal enable
B. switch(config)#udld enable
C. switch(config-if)#udld mode normal
D. switch(config)#udld mode normal
|
| Answer: | B. 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. 10 seconds
B. 5 seconds
C. 2 seconds
D. 30 seconds
E. 7 seconds
F. 15 seconds
|
| Answer: | E. 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. clear udld
D. udld enable
|
| 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 bpduguard
B. show spanning-tree interface
C. show spanning-tree guard
D. show spanning-tree summary
|
| Answer: | D. 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. RSTP
D. TCP
E. RSVP
|
| Answer: | E. RSVP
|
| Explanation: | Integrated services is associated with RSVP, Resource Reservation Protocol, described in RFC 1633. |
|
| Question: | Match the QoS types with their behaviour.
A. Best Effort, Intergrated Services, Differentiated Services
B. No QoS, Per flow, Per hop
|
| Answer: | A. Best Effort, Intergrated Services, Differentiated Services
|
| Explanation: | In Best Effort there is no real QoS mechanism working, the packets are delivered as quick as possible. Integrated Services applies QoS on a per flow base while Differentiated Services does it on a per hop base. |
|
| Question: | Using ISL the CoS is entered where?
A. The upper three bits of the User Field
B. Three bits are added to the User Field
C. Three bytes are added to the User Field
D. The lower three bits of the User Field
E. The lower three bytes of the User Field
F. The upper three bytes of the User Field
|
| Answer: | D. 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. 3 bit IP Presedence
B. 4 bit ToS value
C. 5 bit IP Presedence
D. 4 bit IP Presedence
E. 3 bit ToS value
F. 5 bit ToS value
|
| Answer: | A. 3 bit IP Presedence
B. 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 Point
B. Differentiated Service Classification Point
C. Differentiated Service Classification Protocol
D. Differentiated Service Code Protocol
|
| Answer: | A. 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. 0,1,2,3,4,5,6,7
B. Routine, Priority, Immediate, Flash, Flash override, Critical, Internetwork Control, Network Control
|
| Answer: | B. 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. Network Control
B. Immediate
C. Critical
D. Flash
|
| Answer: | D. 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. Internetwork Control
D. Expedited Forwarding
|
| Answer: | D. 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. Weighted Policers
B. Weighted Round Robin
C. Weighted Fair Queue
D. Microflow Policers
E. Aggregate Policers
|
| Answer: | D. Microflow Policers
E. Aggregate 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. Weighted Round Robin
B. Aggregate Policers
C. FIFO
D. Tail Drop
E. Weighted Random Early Detection
|
| Answer: | D. Tail Drop
E. 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. Egress Queueing
B. Ingress Queueing
C. Congestion Management
D. Congestion Avoidance
E. Tail Drop
|
| Answer: | A. Egress Queueing
C. Congestion Management
|
| 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 WRR
B. 1 strict priority 2 WRR 2 WRED
C. 1 strict priority 2 standard queues 2 WRED
D. 1 strict priority 2 standard queues 2 Tail drop
|
| Answer: | C. 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)#qos trust dscp
B. switch(config-if)#mls qos scp trust
C. switch(config-if)#mls qos trust dscp
D. switch(config-if)#mls qos dscp
|
| Answer: | C. 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-list
B. switch(config-cmap)#match access-list name access-list
C. switch(config-cmap)#match access-group access-list
D. switch(config-cmap)#match access-group name access-list
|
| Answer: | D. 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-cmap)#match protocol protocol name
B. switch(config)#match protocol protocol name
C. switch(config-cmap)#match nbar protocol name
D. switch(config-pmap)#match protocol protocol name
|
| Answer: | A. 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)#policy-map policy-name
B. switch(config-cmap)#policy-map policy-name
C. switch(config-pmap)#policy-map policy-name
D. switch(config)#class-map class-name
|
| Answer: | A. 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. 255
B. 16
C. 32
D. 64
E. 128
F. 256
G. 4
H. 1
|
| Answer: | A. 255
G. 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)#no wrr-queue random-detect queue id
B. switch(config-if)#mls qos tail-drop enable
C. switch(config-if)#mls qos tail-drop
D. switch(config-if)#wrr-queue random-detect queue id
|
| Answer: | A. 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)#mls priority-queue out
B. switch(config-if)#strict-priority-queue out
C. switch(config-if)#mls qos priority-queue out
D. switch(config-if)#priority-queue out
|
| Answer: | D. 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 detail
C. show interface
D. show mls 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. 802.1d
B. 802.5
C. 802.1w
D. 802.1s
|
| Answer: | C. 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. Redundant port
B. Alternate port
C. Designated port
D. Backup port
|
| Answer: | D. 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. Listening
B. Learning
C. Blocking
D. Forwarding
E. Disabled
|
| Answer: | A. Listening
C. Blocking
E. Disabled
|
| 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. Alternate port
B. Point-to-point port
C. Edge port
D. Backup port
|
| Answer: | C. 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. acceptance message
C. information message
D. proposal message
E. agreement message
|
| Answer: | D. proposal message
E. agreement 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. MAC addresses associated with designated port the BPDU are flushed from the CAM.
B. BPDUs with the TC bit set are sent out for 4 times the hello time.
C. BPDUs with the TC bit set are sent out for 6 times the hello time.
D. MAC addresses are flushed from the CAM.
|
| Answer: | D. 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 do we configure an edge port using RSTP?
A. switch(config-if)#spanning-tree portfast
B. switch(config-if)#spanning-tree link-type edge
C. switch(config-if)#spanning-tree mst edge
D. switch(config-if)#spanning-tree rstp edge
|
| Answer: | A. switch(config-if)#spanning-tree portfast
|
| Explanation: | In order to configure an edge port in RSTP we use the spanning-tree portfast interface configuration command. |
|
| Question: | How can we change a half-duplex port to a point-to-point port in RSTP?
A. switch(config-if)#spanning-tree link-type point-to-point
B. switch(config-if)#spanning-tree point-to-point
C. switch(config-if)#spanning-tree port-type point-to-point
D. switch(config-if)#spanning-tree port point-to-point
|
| Answer: | A. 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. 350
B. 1
C. Can not tell
D. 500
|
| Answer: | A. 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. region name
C. revision number
D. domain name
E. instance-to-Vlan mapping table
F. Vlan-to-instance mapping table
|
| Answer: | A. configuration name
C. revision number
E. 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 mst
B. switch(config)#mst enable
C. switch(config)#spanning-tree mode mst
D. switch(config)#spanning-tree mst configuration
|
| Answer: | C. 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)#revision version
D. switch(config-mst)#spanning-tree mst revision version
|
| Answer: | C. switch(config-mst)#revision version
|
| Explanation: | In order to assign the MST revision number we use the revision version MST configuration command. |
|
| Question: | What is used in a single, loop-free topology inside a MST region?
A. Internal Spanning Tree
B. Common Spanning Tree
C. Instance Spanning Tree
D. Per Vlan Spanning Tree
|
| Answer: | A. 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 layer-2
B. switch(config-if)#switchport mode layer-2
C. switch(config-if)#switchport
D. switch(config-if)#no switchport
|
| Answer: | C. 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: | Mulitlayer switching consists of which two parts?
A. Routing engine
B. Route processor
C. SVI
D. Switching engine
|
| Answer: | B. Route processor
D. Switching engine
|
| 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. IP TTL is less then 10.
B. More then one entry to the destination in the FIB Table
C. Encapsulation type is not supported.
D. MTU is exceeded and there is need for fragmentation.
|
| Answer: | C. Encapsulation type is not supported.
D. MTU is exceeded and there is need for fragmentation.
|
| Explanation: | none |
|
| Question: | How do we change the bridge priority in mst?
A. switch(config)#spanning-tree mst priority bridge_priority instance instance_id
B. switch(config)#spanning-tree mst priority bridge_priority
C. switch(config-mst)#instance_id priority bridge_priority
D. switch(config)#spanning-tree mst instance_id priority bridge_priority
|
| Answer: | D. 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-time seconds
B. switch(config)#spanning-tree mst forward-delay seconds
C. switch(config-mst)#spanning-tree mst forward-delay seconds
D. switch(config)#spanning-tree mst instance instance_id forward-time seconds
E. switch(config)#spanning-tree mst instance instance_id forward-delay seconds
F. switch(config-mst)#spanning-tree mst forward-time seconds
|
| Answer: | A. 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: | How do we configure a Catalyst 3550 interface to provide Layer 3 functionality?
A. switch(config)#interface type mod/num
switch(config-if)#switchport access ip
switch(config-if)#ip address ip address mask
B. switch(config)#interface type mod/num
switch(config-if)#ip address ip address mask
C. switch(config)#interface type mod/num
switch(config-if)#switchport mode layer3
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: | How do we assign an IP Address to a SVI?
A. switch(config)#interface vlan vlan_id switch(config-if)#ip address ip address mask
B. switch(config)#interface vlan vlan_id switch(config-vlan)#ip address ip address mask
C. switch(config)#interface svi type mod/num switch(config-if)#ip address ip address mask
D. switch(config)#interface vlan vlan_id switch(config-if-svi)#ip address ip address mask
|
| Answer: | A. 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 portion of the FIB table called that contains the Layer 2 information for the next-hop?
A. CAM
B. TCAM
C. Adjacency table
D. MAC table
|
| Answer: | C. Adjacency table
|
| Explanation: | The portion of the FIB that contains the Layer 2 information about the next-hop is called the adjacency table. |
|
| Question: | What is the CEF Glean state?
A. When further processing is needed by the Layer 3 engine, like fragment the packet, compress the packet,...
B. 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.
C. 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.
D. 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.
|
| Answer: | D. 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: | When the FIB table is replicated across any number of independent Layer 3 forwarding engines, we are using ____________.
A. Distributed CEF
B. Expedited CEF
C. Assured CEF
D. Accelerated 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 limiting
B. ARP queueing
C. ARP discarding
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: | On a Catalyst 3550 how do we enable CEF?
A. switch(config)#cef enable
B. switch(config0#ip cef
C. CEF is enabled by default
D. switch(config)#mls cef
|
| Answer: | C. 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 vlan-bridge
B. switch(config-vlan)#bridge-group bridge-group protocol protocol_name
C. switch(config)#bridge-group bridge-group protocol protocol_name
D. switch(config)#bridge-group bridge-group protocol vlan-bridge
|
| Answer: | D. 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. 128
B. 8
C. 1
D. 16
E. 32
F. 64
G. 31
|
| Answer: | G. 31
|
| Explanation: | You can configure up to 31 bridgegroups on a switch. |
|
