Improving Redundant Switched Topologies with EtherChannel Flashcards
Which two statements about the EtherChannel technology are true? (Choose two.)
A. EtherChannel provides increased bandwidth by bundling existing FastEthernet 100 Mbps and GigabitEthernet 1Gbps interfaces into a single EtherChannel.
B. STP can block one of the physical links in an EtherChannel to prevent a loop.
C. You can configure multiple EtherChannel links between two switches, as long as you are within the allowed number of physical ports.
D. EtherChannel does not allow load balancing of traffic among the physical links within the EtherChannel.
E. EtherChannel allows redundancy in case one or more links in the EtherChannel fail.
C. You can configure multiple EtherChannel links between two switches, as long as you are within the allowed number of physical ports.
E. EtherChannel allows redundancy in case one or more links in the EtherChannel fail.
The correct answers are “You can configure multiple EtherChannel links between two switches, as long as you are using allowed number of physical ports,” and “EtherChannel allows redundancy in case one or more links in the EtherChannel fail.” STP does not block physical link within an EtherChannel. EtherChannel achieves the increase in bandwidth by using load balancing to utilize individual links. Interfaces of different types cannot be aggregated.
Which statement about the LACP protocol is true?
A. LACP provides dynamic creation of EtherChannel and does not maintain them.
B. LACP groups physical links into an EtherChannel only if it determines that they have the same speed, duplex mode, native VLAN, VLAN range, trunking status, and trunk type.
C. Ports that you configured to use LACP can form EtherChannels with ports that you configure to form EtherChannel unconditionally.
D. You cannot use LACP protocol to connect devices of different manufacturers.
B. LACP groups physical links into an EtherChannel only if it determines that they have the same speed, duplex mode, native VLAN, VLAN range, trunking status, and trunk type.
You issued the show etherchannel port-channel command that displayed the output as shown below. Which two statements about the EtherChannel are true? (Choose two.)
SW1# show etherchannel port-channel
< — output omitted —>
Port-channel: Po1 (Primary Aggregator)
Age of the Port-channel = 0d:01h:11m:56s
Logical slot/port = 16/0 Number of ports = 2
HotStandBy port = null
Port state = Port-channel Ag-Inuse
Protocol = LACP
Port security = Disabled
Ports in the Port-channel:
Index Load Port EC state No of bits
——+——+——+——————+———–
0 00 Et0/2 Active 0
0 00 Et0/3 Active 0
A. The configuration used group identifier 16 and static mode to bundle an interface to the EtherChannel.
B. The configuration used group identifier 1 and LACP protocol to bundle an interface to the EtherChannel.
C. The EtherChannel is disabled.
D. All bundled links are used.
E. Only two links are used. Other links are not in use.
B. The configuration used group identifier 1 and LACP protocol to bundle an interface to the EtherChannel.
D. All bundled links are used.
Which command did you use on SW1 switch, to include interfaces in the logical port channel?
A. channel-group 12 mode on
B. channel-group 12 mode passive
C. channel-group 12 mode active
D. channel-group 12 mode auto
C. channel-group 12 mode active
Which command did you use on SW2 switch to include interfaces in the logical port channel?
A. channel-group 12 mode passive
B. channel-group 12 mode active
C. channel-group 12 mode auto
D. channel-group 12 mode on
A. channel-group 12 mode passive
The correct answer is “channel-group 12 mode passive.” The tasks required to use standardized protocol and for switch SW2 only to respond to EtherChannel initiation requests. Therefore the LACP protocol must be used in the passive mode. The port channel identifier (the number chosen for the channel-group) can differ on both sides of the link. Therefore, the number 21 in the command is a valid syntax. The on mode does not involve protocols and bundles an interface immediately. Auto is not a valid mode.
On switch SW1, issue the show interfaces trunk command. Which port is indicated as the trunking port in the output?
A. po12
B. Ethernet0/0
C. Ethernet0/1
D. Ethernet0/2
E. Ethernet0/3
A. po12
On SW2, issue the show etherchannel summary command. Which letters indicate the status of the aggregated link?
A. RU
B. SU
C. I
D. Sf
B. SU
The correct answer is “SU.” At the beginning of the output, there is an explanation of all letter indications used in the output. Aggregated link status is indicated in the table at the end, under the Port-channel column in the brackets next to the port channel label. If you configured the switches correctly, you should see Po12(SU).
The administrator has configured an EtherChannel link between switches SW1 and SW2. His configuration is shown in the exhibit. However, the EtherChannel does not form. What is the likely reason for the issue?
SW1(config)# interface range FastEthernet0/1 - 2
SW1(config-if-range)# channel-group 11 mode active
SW1(config-if-range)# exit
SW1(config)# interface port-channel 11
SW1(config-if)# switchport mode trunk
SW1config-if)# switchport trunk allowed vlan 1,2,10
SW2(config)# interface range FastEthernet0/4 - 5
SW2(config-if-range)# channel-group 1 mode active
SW2(config-if-range)# exit
SW2(config)# interface port-channel 1
SW2(config-if)# switchport mode trunk
SW2(config-if)# switchport trunk allowed vlan 1,2,20
A. The configurations do not use the same channel-group number.
B. The configurations do not form between the same interfaces—SW1 is bundling ports FastEthernet 0/1 and 0/2, while SW2 is bundling ports FastEthernet 0/4 and 0/5.
C. Logical interfaces cannot be trunks.
D. The trunk configuration on the switches is not consistent.
D. The trunk configuration on the switches is not consistent.
Which option correctly describes the “on” mode regarding EtherChannel?
A. The EtherChannel will form only if the other side is set to on.
B. The EtherChannel will form if the other side is set to active.
C. If the other side is set to negotiate parameters through PAgP, EtherChannel will not form, because PAgP is a proprietary protocol.
D. If the other side is set to negotiate parameters through LACP, EtherChannel will form, because negotiations with standard protocol will be successful.
C. The Etherchannel will be successful if the other side is set to passive.
A. The EtherChannel will form only if the other side is set to on.
You have just configured two EtherChannels between two switches. Each EtherChannel contains 3 physical links. Which option describes how Layer 2 STP will react?
A. It will block one physical link within one of the EtherChannels.
B. It will block one entire EtherChannel.
C. It will block one physical link within each EtherChannel.
D. It will not block any links.
B. It will block one entire EtherChannel.
Which two statements are true about the Layer 3 EtherChannel? (Choose two.)
A. A Layer 3 port channel interface behaves like a port on a router.
B. Layer 3 EtherChannel is established between Layer 2 and Layer 3 switches.
C. Layer 3 EtherChannel can have Layer 2 member interfaces.
D. Layer 3 EtherChannel is only used on the links towards service providers.
E. Layer 3 EtherChannel can be used for routing protocol message exchange.
F. On Layer 3 EtherChannel, you should disable Spanning Tree Protocol.
B. Layer 3 EtherChannel is established between Layer 2 and Layer 3 switches.
An administrator is configuring EtherChannel on switch SW3. She is starting the configuration by shutting down a range of interfaces, as shown below. Why is she doing so?
SW3(config)# interface range Ethernet0/2 - 3
SW3(config-if-range)# shutdown
A. The interfaces must be shut down when they are bundled into EtherChannel.
B. The interfaces must be shut down to change their speed and duplex.
C. The shutdown interfaces do not create activity on the link, so incomplete configuration will not produce undesired results.
D. The interfaces that are not part of the EtherChannel must be shut down.
C. The shutdown interfaces do not create activity on the link, so incomplete configuration will not produce undesired results.
Which four interface characteristics must match for a link to be included into EtherChannel? (Choose four.)
A. interface type
B. switchport mode
C. interface speed
D. VLAN
E. STP role
F. hostname
G. interface descriptions
A. interface type
B. switchport mode
C. interface speed
D. VLAN
An administrator is troubleshooting an EtherChannel link. Which two commands will provide EtherChannel bundled link information and status of each bundled link? (Choose two.)
A. show etherchannel port-channel
B. show etherchannel summary
C. show interface Port-channel
D. show interfaces status
E. show spanning-tree
A. show etherchannel port-channel
B. show etherchannel summary
