CCNA Switching and Network Access Practice Question
Network Topology
You are connected to Switch1. Configure an LACP EtherChannel between Switch1 and Switch2 using interfaces GigabitEthernet0/1 and GigabitEthernet0/2. The channel must be in active mode on both sides, and the port-channel interface must have VLAN 10 as the access VLAN. The current configuration has a speed/duplex mismatch and inconsistent VLAN assignments preventing the channel from forming. Verify the channel is up using 'show etherchannel summary'.
⚠ Common exam trap
The exam trap here is that candidates may focus only on resolving the speed/duplex and VLAN mismatches but forget to check the LACP mode requirement. Also, they might confuse LACP modes (active/passive) with PAgP modes (desirable/auto). Always verify that the mode matches the protocol and the requirement.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Set speed auto on Gi0/1 and Gi0/2, set duplex auto on both, change access VLAN on Gi0/2 to 10, change access VLAN on Port-channel1 to 10, and set channel-group mode active on both interfaces.
The EtherChannel is not forming due to three issues: (1) Speed mismatch: Gi0/1 is set to 100 Mbps while Gi0/2 is 1000 Mbps; both must match (e.g., auto). (2) Duplex mismatch: Gi0/1 is half-duplex, Gi0/2 is full-duplex; both must be the same (e.g., full). (3) VLAN mismatch: Gi0/1 is in VLAN 10, Gi0/2 in VLAN 20, and Port-channel1 is in VLAN 1; all access VLANs must be consistent (set to VLAN 10). Additionally, the channel-group mode should be 'active' on both interfaces for LACP. The solution involves setting speed and duplex to auto, changing the access VLAN on Gi0/2 and the port-channel to VLAN 10, and setting channel-group mode to active.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Set speed auto on Gi0/1 and Gi0/2, set duplex auto on both, change access VLAN on Gi0/2 to 10, change access VLAN on Port-channel1 to 10, and set channel-group mode active on both interfaces.
Why this is correct
This is correct because it resolves all three issues: speed/duplex mismatch (setting auto allows negotiation to common values), VLAN inconsistency (setting both member interfaces and port-channel to VLAN 10), and LACP mode (active on both sides ensures negotiation).
- ✗
Set speed 1000 on Gi0/1, set duplex full on Gi0/1, change access VLAN on Gi0/1 to 20, change access VLAN on Port-channel1 to 20, and set channel-group mode passive on both interfaces.
Why it's wrong here
This is incorrect because forcing speed to 1000 on Gi0/1 may not be supported if the interface is limited to 100 Mbps, and changing VLAN to 20 does not match the requirement for VLAN 10. Also, passive mode on both sides prevents LACP from initiating negotiation.
- ✗
Set speed 100 on Gi0/2, set duplex half on Gi0/2, change access VLAN on Gi0/1 to 20, change access VLAN on Port-channel1 to 20, and set channel-group mode desirable on both interfaces.
Why it's wrong here
This is incorrect because 'desirable' is a PAgP mode, not LACP. LACP uses 'active' or 'passive'. Also, setting speed to 100 and duplex half on Gi0/2 degrades performance and may not match the requirement for auto or full duplex.
- ✗
Set speed auto on Gi0/1 and Gi0/2, set duplex auto on both, change access VLAN on Gi0/1 to 10, change access VLAN on Port-channel1 to 10, and set channel-group mode active on Gi0/1 and passive on Gi0/2.
Why it's wrong here
This is incorrect because while it resolves speed/duplex and VLAN issues, the LACP mode mismatch (active on one side, passive on the other) will still allow the channel to form if the active side initiates. However, the requirement states 'active mode on both sides', so this does not meet the requirement.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The 200-301 exam frequently reuses these exact scenarios with slightly different constraints.
✓Set speed auto on Gi0/1 and Gi0/2, set duplex auto on both, change access VLAN on Gi0/2 to 10, change access VLAN on Port-channel1 to 10, and set channel-group mode active on both interfaces.Correct answer▾
Why this is correct
This is correct because it resolves all three issues: speed/duplex mismatch (setting auto allows negotiation to common values), VLAN inconsistency (setting both member interfaces and port-channel to VLAN 10), and LACP mode (active on both sides ensures negotiation).
✗Set speed 1000 on Gi0/1, set duplex full on Gi0/1, change access VLAN on Gi0/1 to 20, change access VLAN on Port-channel1 to 20, and set channel-group mode passive on both interfaces.Wrong answer — click to see why▾
Why this is wrong here
The specific factual error: passive mode on both sides will not form an LACP EtherChannel because neither side initiates negotiation; at least one side must be active.
Why candidates choose this
Candidates pick this because they know speed/duplex must match but may incorrectly assume forcing a specific speed is acceptable, and they may confuse passive with active mode.
✗Set speed 100 on Gi0/2, set duplex half on Gi0/2, change access VLAN on Gi0/1 to 20, change access VLAN on Port-channel1 to 20, and set channel-group mode desirable on both interfaces.Wrong answer — click to see why▾
Why this is wrong here
The specific factual error: 'desirable' is a PAgP mode; LACP uses 'active' or 'passive'. Using 'desirable' would not form an LACP EtherChannel.
Why candidates choose this
Candidates pick this because they may confuse PAgP and LACP modes, or think 'desirable' is a valid LACP mode. Also, they might think matching to the slower speed is acceptable.
✗Set speed auto on Gi0/1 and Gi0/2, set duplex auto on both, change access VLAN on Gi0/1 to 10, change access VLAN on Port-channel1 to 10, and set channel-group mode active on Gi0/1 and passive on Gi0/2.Wrong answer — click to see why▾
Why this is wrong here
The specific factual error: the requirement explicitly states 'active mode on both sides', so setting one side to passive violates the requirement, even though the channel might still form.
Why candidates choose this
Candidates pick this because they know that an active/passive combination works for LACP, but they overlook the explicit requirement for both sides to be active.
Analysis generated from the official 200-301blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Visual reference
Go deeper
Related to this question
Learn chapter
Interpreting Packet Capture Output for Layer 2/3 Troubleshooting
Key term
EtherChannel
EtherChannel is a technology that bundles multiple physical Ethernet links into a single logical link to increase bandwidth and provide redundancy.
Key term
Duplex mismatch
A duplex mismatch occurs when two connected network devices are configured with different duplex settings (one half-duplex, one full-duplex), leading to poor performance and data errors.
About these practice questions
Courseiva writes every 200-301 question from scratch — 1,389 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 200-301 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 200-301 exam.