CCNA Switching and Network Access Practice Question
Exhibit
SW1# show etherchannel detail
Channel-group listing:
Group: 1
----------
Group state = L2
Ports: 2 Maxports = 8
Port-channels: 1 Max Port-channels = 1
Protocol: LACP
Ports in the group:
Port: Gi0/1
Port state = Up Cntrl-fwd/bndl In-bndl Mstr
Channel group: 1 Mode: Active
Port-channel = Po1
Age of the port in the current state: 0d:00h:12m:10s
Port: Gi0/2
Port state = Down Cntrl-fwd/susp Not-in-bndl
Channel group: 1 Mode: Active
Native vlan mismatch: local 20, partner 1Refer to the exhibit. A network engineer configured an EtherChannel between SW1 and SW2 using LACP. After the configuration is applied, the Port-channel 1 interface remains in a down state and does not pass traffic. The engineer runs the show etherchannel detail command on SW1. Based on the output, what is the most likely cause of the problem?
⚠ Common exam trap
Candidates often assume that any VLAN mismatch on a member port will bring down the entire port-channel. In reality, only the mismatched port is affected; the port-channel may still operate if other ports are properly configured.
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
✓
The interface Gi0/1 is administratively down.
An EtherChannel requires all member ports to have consistent VLAN configurations. However, if one port (Gi0/2) has a native VLAN mismatch, only that port is suspended/excluded from the channel. The port-channel can still become active using other valid members. In this scenario, the port-channel remains down because Gi0/1 is administratively down, leaving no valid member ports to form the channel. The show etherchannel detail output would indicate Gi0/1 in an administratively down state and Gi0/2 in a suspended state due to the native VLAN mismatch.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The native VLAN is mismatched on member interface Gi0/2.
Why it's wrong here
The output explicitly states 'Native vlan mismatch: local 20, partner 1' for Gi0/2, confirming that the 802.1Q native VLAN differs between the local switch and its neighbor. In an EtherChannel, all member trunks must have identical native VLANs; when the native VLAN does not match, the switch suspends the member port, as shown by the 'susp' state, to prevent frame misdelivery. This mismatch is reported by CDP and is the direct cause of the port-channel member being non-forwarding.
When this WOULD be correct
The line 'Native vlan mismatch: local 20, partner 1' proves that the native VLAN on Gi0/2 (20) does not match the partner’s expected VLAN (1).
- ✗
The load-balancing method on the port-channel is set incorrectly to src-dst-ip.
Why it's wrong here
The load-balancing method, such as src-dst-ip, determines how an EtherChannel distributes traffic across its active member links, but it has no effect on whether a link is placed into a 'susp' state. A suspended port results from a physical or configuration incompatibility between the local port and its peer, not from the hashing or distribution algorithm. Moreover, the exhibit shows a native VLAN mismatch on Gi0/2, and no load-balancing configuration appears in the output, so this answer is incorrect.
- ✓
The interface Gi0/1 is administratively down.
Why this is correct
The exhibit shows Gi0/1 with state 'Up Cntrl-fwd/bndl In-bndl Mstr', meaning it is up, forwarding, bundled, and acting as the master port. An administratively down interface would show 'Down' with 'admin down' status, which is not the case.
- ✗
Spanning Tree Protocol has placed the port-channel in a blocking state due to a loop.
Why it's wrong here
Spanning Tree Protocol prevents Layer 2 loops by placing redundant paths into a blocking state, but STP operates on the logical PortChannel interface, not on individual member ports, and it would not mark Gi0/2 as 'susp' in an EtherChannel status output. The 'susp' designation is an EtherChannel-specific condition caused by a configuration mismatch with the neighbor, such as the documented native VLAN mismatch on Gi0/2. Since the exhibit contains no STP state or topology-change indication, the blocking-state explanation is not supported.
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.
✓The interface Gi0/1 is administratively down.Correct answer▾
Why this is correct
The exhibit shows Gi0/1 with state 'Up Cntrl-fwd/bndl In-bndl Mstr', meaning it is up, forwarding, bundled, and acting as the master port. An administratively down interface would show 'Down' with 'admin down' status, which is not the case.
✗The native VLAN is mismatched on member interface Gi0/2.Wrong answer — click to see why▾
Why this is wrong here
The output explicitly states 'Native vlan mismatch: local 20, partner 1' for Gi0/2, confirming that the 802.1Q native VLAN differs between the local switch and its neighbor. In an EtherChannel, all member trunks must have identical native VLANs; when the native VLAN does not match, the switch suspends the member port, as shown by the 'susp' state, to prevent frame misdelivery. This mismatch is reported by CDP and is the direct cause of the port-channel member being non-forwarding.
★ When this WOULD be the correct answer
The line 'Native vlan mismatch: local 20, partner 1' proves that the native VLAN on Gi0/2 (20) does not match the partner’s expected VLAN (1).
✗The load-balancing method on the port-channel is set incorrectly to src-dst-ip.Wrong answer — click to see why▾
Why this is wrong here
Load-balancing configuration does not influence the bundle state of a port-channel; it only affects frame distribution. The output shows a physical/logical inconsistency, not a hashing algorithm problem.
✗Spanning Tree Protocol has placed the port-channel in a blocking state due to a loop.Wrong answer — click to see why▾
Why this is wrong here
A common misconception is that any down or suspended link indicates an STP loop. However, 'show etherchannel detail' presents the explicit reason, and the native VLAN mismatch line directly contradicts this option.
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
Troubleshoot: EIGRP Neighbor Won't Form
Key term
VLAN
A VLAN logically segments a physical network into isolated broadcast domains without requiring separate physical switches.
Key term
Native VLAN mismatch
A Native VLAN mismatch occurs when two connected switches have different Native VLANs configured on the trunk port, causing control traffic like CDP, DTP, and BPDUs to be sent on the wrong VLAN and potentially creating security vulnerabilities or connectivity issues.
About these practice questions
This 200-301 question is part of Courseiva's 1,450-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam 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.