CCNA 2 Module 6 Quiz – Etherchannel (Answers)

1. An EtherChannel link using LACP was formed between two switches, S1 and S2. While verifying the configuration, which mode combination could be utilized on both switches?​

  • S1-passive and S2-passive
  • S1-on and S2-active
  • S1-on and S2-passive
  • S1-passive and S2-active

Explanation: An EtherChannel link will be formed using LACP when both switches are in on mode or in active mode, or when one of them is in passive mode and the other is in active mode.

2. When a range of ports is being configured for EtherChannel, which mode will configure PAgP so that it initiates the EtherChannel negotiation?

  • active
  • desirable
  • passive
  • auto

Explanation: The command channel-group mode active enables LACP unconditionally, and the command channel-group mode passive enables LACP only if the port receives an LACP packet from another device. The command channel-group mode desirable enables PAgP unconditionally, and the command channel-group mode auto enables PAgP only if the port receives a PAgP packet from another device.

3. Which three interface parameters must match for an EtherChannel to form? (Choose three.)

  • PortFast mode
  • spanning-tree state
  • allowed VLANs
  • native VLAN
  • EtherChannel mode
  • trunking mode

Explanation: There are some EtherChannel modes that can be different and an EtherChannel will form, such as auto/desirable and active/passive. A port that is currently in the spanning tree blocking mode or has been configured for PortFast can still be used to form an EtherChannel.

4. What are three advantages of using EtherChannel technology? (Choose three.)

  • Configuration tasks can be done on the EtherChannel interface.
  • A spanning tree recalculation is not required when a single link within the channel goes down.
  • The Spanning Tree Protocol shuts down the unused interfaces in the bundle to avoid loops.
  • There is no need to upgrade links to faster connections to increase bandwidth.
  • EtherChannel uses multiple logical links to provide redundancy.
  • Load balancing is not needed with EtherChannel.

Explanation: Most configuration tasks can be done on the EtherChannel interface, rather than on individual ports. Existing ports can be used, eliminating the need to upgrade ports to faster speeds. Spanning Tree Protocol runs on EtherChannel links in the same manner as it does on regular links, but it does not recalculate when an individual link within the channel goes down. EtherChannel also supports load balancing.

5. A network administrator is configuring an EtherChannel link between two physical ports on a switch. Which statement describes the result when one of the physical ports fails?

  • An STP recalculation is needed.
  • The EtherChannel link fails.
  • The EtherChannel stops transmitting data until it is restarted.
  • The EtherChannel continues transmitting data with reduced bandwidth.

Explanation: An EtherChannel is seen as one logical connection. The loss of one physical link within the channel does not create a change in the topology and therefore a spanning tree recalculation is not required. When one of the member ports in the EtherChannel fails, the EtherChannel link remains functional, although its overall throughput decreases because of a lost link within the EtherChannel.

6. When EtherChannel is implemented, multiple physical interfaces are bundled into which type of logical connection?

  • port channel
  • loopback
  • VLAN interface
  • interface range

Explanation: When EtherChannel is being configured, the first step is to specify what physical ports will be used in an EtherChannel group. The second step is to create the logical EtherChannel port channel interface which contains the group of physical interfaces.

7. When a range of ports is being configured for EtherChannel by the use of PAgP, which mode will form the bundled channel only if the port receives PAgP packets from another device?

  • desirable
  • active
  • auto
  • passive

Explanation: The command channel-group mode active enables LACP unconditionally, and the command channel-group mode passive enables LACP only if the port receives an LACP packet from another device. The command channel-group mode desirable enables PAgP unconditionally, and the command channel-group mode auto enables PAgP only if the port receives a PAgP packet from another device.

8. Which two load balancing methods can be implemented with EtherChannel technology? (Choose two.)

  • source IP to destination IP
  • source MAC to destination MAC
  • destination IP to destination MAC
  • destination MAC to source MAC
  • destination IP to source IP
  • destination MAC to destination IP

Explanation: Source MAC to destination MAC load balancing and source IP to destination IP load balancing are two implementation methods used in EtherChannel technology.

9. Which function is provided by EtherChannel?

  • enabling traffic from multiple VLANs to travel over a single Layer 2 link
  • spreading traffic across multiple physical WAN links
  • dividing the bandwidth of a single link into separate time slots
  • creating one logical link by using multiple physical links between two LAN switches

Explanation: EtherChannel technology allows the grouping, or aggregating, of several Fast Ethernet or Gigabit switch ports into one logical channel.

10. Which statement is true about EtherChannel technology?

  • All configuration tasks must be done on the individual ports in the EtherChannel link.
  • STP does not run on redundant EtherChannel links.
  • EtherChannel uses existing switch ports.
  • Links must be upgraded to support EtherChannel.

Explanation: EtherChannel relies on existing switch ports, so there is no need to upgrade the links. Some configuration tasks are done on individual ports and some configuration tasks are done on the EtherChannel group. STP operates on EtherChannel in the same manner as it does on other redundant links.

11. Which two mode combinations would result in the successful negotiation of an EtherChannel? (Choose two.)

  • active; on
  • passive; auto
  • desirable; desirable
  • desirable; active
  • active; passive
  • auto; auto

Explanation: The combinations of modes that will form an EtherChannel are as follows: on/on, active/passive, active/active, desirable/auto, and desirable/desirable.

12. Which two protocols are link aggregation protocols? (Choose two.)

  • EtherChannel
  • STP
  • PAgP
  • 802.3ad
  • RSTP

Explanation: The two protocols that can be used to form an EtherChannel are PAgP (Cisco proprietary) and LACP, also know as IEEE 802.3ad. STP (Spanning Tree Protocol) or RSTP (Rapid Spanning Tree Protocol) is used to avoid loops in a Layer 2 network. EtherChannel is the term that describes the bundling of two or more links that are treated as a single link for spanning tree and configuration.

13. When a range of ports is being configured for EtherChannel, which mode will configure LACP so that it initiates the EtherChannel negotiation?

  • active
  • auto
  • desirable
  • passive

Explanation: The command channel-group mode active enables LACP unconditionally, and the command channel-group mode passive enables LACP only if the port receives an LACP packet from another device. The command channel-group mode desirable enables PAgP unconditionally, and the command channel-group mode auto enables PAgP only if the port receives a PAgP packet from another device.

14. What will happen if a network administrator puts a port that is part of an EtherChannel bundle into a different VLAN than the other ports in that bundle?

  • The EtherChannel will fail.
  • The EtherChannel bundle will stay up if the ports were configured with no negotiation between the switches to form the EtherChannel.
  • The EtherChannel bundle will stay up if either PAgP or LACP is used.
  • The EtherChannel bundle will stay up only if LACP is used.
  • The EtherChannel bundle will stay up only if PAgP is used.

Explanation: All ports in an EtherChannel bundle must either be trunk ports or be access ports in the same VLAN. If VLAN pruning is enabled on the trunk, the allowed VLANs must be the same on both sides of the EtherChannel.

15. When a range of ports is being configured for EtherChannel, which mode will configure LACP on a port only if the port receives LACP packets from another device?

  • auto
  • passive
  • desirable
  • active

Explanation: The command channel-group mode active enables LACP unconditionally, and the command channel-group mode passive enables LACP only if the port receives an LACP packet from another device. The command channel-group mode desirable enables PAgP unconditionally, and the command channel-group mode auto enables PAgP only if the port receives a PAgP packet from another device.


Related Articles

guest
0 Comments
Inline Feedbacks
View all comments