Refer to the exhibit.
Switch-1 and Switch-2 connect on interface A23. The switches experience a connectivity issue. The network administrator sees that both switches show this interface as up. The administrator sees the output shown in the exhibit on Switch-1.
What is a typical issue that could cause this output?
The exhibit shows that the UniDirectional Link Detection (UDLD) status is in a failure state, indicating a problem with the link. One common cause of such a failure is a mismatch in VLAN configuration between the two connected switches. If the untagged VLANs do not match, UDLD will detect a problem because the keepalive packets will not be properly exchanged and recognized across the link. This configuration issue leads to the interface showing as up but unable to maintain proper communication, which fits with the observed symptoms in the exhibit.
I think correct answer is B
I think correct answer is not showed on the list. It should be a physical error on the link
answer is not showed https://support.hpe.com/hpesc/public/docDisplay?docId=emr_na-c01978780
B. With UDLD think about physical cable connectivity monitoring between two points. Look at TX/RX keepalives, should one side fail to receive a message in 20 secs (i.e. message / 5 secs , retries 4; thus 4 x 5 = 20 secs), a failure occurs.
B. Also, if a switch is in the middle of the other switch does not accept UDLD messages, it is better to tag the UDLD for it to reach the other end.
I agree with B because in the case to only possible error is this. On the documentation it is clearly defined that the untagged VLAN must match.
It can only B because matching the VLAN is essential.