2960-X FlexStack

[branson-yang]

I am testing FlexStack in my lab using two Catalyst 2960-X switches running IOS 15.2(7)E14.

While the stack appears to be fully formed and healthy according to show switch detail and show switch stack-ring speed, there is an inconsistency in the output of show switch stack-ports summary. Specifically, the member switch's stack ports are flagged as Link OK: No and Link Active: No.

Device & Stack Status (show switch detail):

Switch/Stack Mac Address : 
                                           H/W   Current
Switch#  Role    Mac Address     Priority Version  State
----------------------------------------------------------
*1       Master acf5.xxxx.yyyy     15     4       Ready
 2       Member acf5.xxxx.yyyy     1      4       Ready

         Stack Port Status             Neighbors
Switch#  Port 1     Port 2           Port 1   Port 2
--------------------------------------------------------
  1        Ok         Ok                2        2
  2        Ok         Ok                1        1

Stack Ring Speed (show switch stack-ring speed):

Stack Ring Speed         : 20G
Stack Ring Configuration : Full
Stack Ring Protocol      : FlexStack

Stack Ports Summary (show switch stack-ports summary):

Switch#/  Stack   Neighbor   Cable     Link   Link   Sync       #          In
 Port#     Port               Length    OK   Active   OK     Changes   Loopback
         Status                                              To LinkOK
--------  ------  --------  --------  ----  ------  ----  ---------  --------
  1/1     OK         2       50 cm     Yes    Yes    N/A        0        No
  1/2     OK         2       50 cm     Yes    Yes    N/A        0        No
  2/1     OK         1       50 cm     No     No     N/A        0        No
  2/2     OK         1       50 cm     No     No     N/A        0        No

Observations:

1. The local switch (Switch 1 / Master) correctly reflects Link OK: Yes and Link Active: Yes.
2. The remote switch (Switch 2 / Member) shows Cable Length: 50 cm and Neighbor: 1, yet reports Link OK: No and Link Active: No.
3. The stack topology is complete (Full, 20G), both members are Ready, and traffic forward works as expected.

Is this a known cosmetic/IPC polling bug in 15.2(7)E14 where the Master fails to pull the ASIC register link flags from the remote member switch? Any known Bug ID or official explanation for this behavior?

Thanks in advance!

[Singhaam · Accepted solution]

@branson-yang To troubleshoot and isolate this telemetry reporting discrepancy, inspect the physical FlexStack LEDs on the rear panel of Switch 2 to verify that they are solid green, which confirms that the physical hardware links and cables are functioning correctly.
Next, perform a role reversal by temporarily adjusting the switch priorities (switch 2 priority 15 and switch 1 priority 1) and reloading the stack; if the reporting error persistently follows Switch 2 regardless of its active role, it confirms a local member IPC telemetry caching bug unique to that specific hardware and software combination.
Finally, monitor the system log files to ensure that no continuous syslog messages or stack-ring flaps are being generated, allowing you to safely ignore the summary table discrepancy if the logs remain entirely clean.