Emergency Responder not finding all switchports on Catalyst 9300 stack

[Iyad Musleh]

We are running Cisco Emergency Responder version 11.5.4.50000-6 and trying to discover phones connected to a Catalyst 9300 stack (C9300-48P) on version 16.08.01a.  There are three member switches connected via StackWise and the stack is fully operational.   CER detects the switchports and phones connected to the switch 1 and 2, but it doesn't even detect the ports of switch 3.  I re-ran "Locate switch-port", but no success.  It's as if this stack only had two members.  I check the logs on CER and there's no indication of discovery errors.  Running CDP command on switch shows ports and phones of all members of the stack.

I should mention that switch 3 was added later to the stack, after switches 1 and 2 were stacked and fully operational for a while beforehand.

What could be causing CER to miss switch 3 of this stack?  Is there a potential compatibility issue?  Or, do one or more CER services need to be restarted?

[Anthony Holloway · Accepted solution]

Did you see this?

https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvq17310

It's not much help, but at least it let's you know that others are having the same problem. I'd recommend opening a TAC case and asking about this defect, or if you have a good relationship with your Cisco SE, talk to them.

[Iyad Musleh]

Thanks Anthony for the quick response. I did indeed open a case with TAC.  After collecting logs and configs from both CER and the switch, they recommended that we reboot the switch stack to resolve the problem.  Apparently, this is what others did to resolve the problem.  Probably has something to do with how the 3rd member of the stack was initially brought on-line.  We'll be doing that later this week. If it doesn't resolve the problem, I'll update this posting. 

[Anthony Holloway]

Ok, cool. I hope that does resolve it for you in the short term, but I also hope there's a long term fix in there somewhere too. Perhaps you can even convince TAC to update the bug with a workaround stating reboot the whole stack. I look forward to the conclusion of your adventure. Good luck!

[RL5901]

TAC and Developers may not know why this is happening or how to fix it.

I also ran into this problem. I opened a TAC case and Cisco Bug ID CSCvq17310 was identified running the CLI command (i.e., SNMP walk). The fix recommended was to upgrade CER from 11.5(4)SU2 to 11.5(4)SU4 with the reason provided that 11.5(4)SU2 did not support the stacked Cisco 9300 switches, but Release Notes show that 11.5(4)SU2 does support the Cisco 9300 switches. In fact, the Release Notes are identical from 11.5(4)SU2 through 12.5(1)SU3. 

In conclusion, I think TAC doesn't even know why this is happening or if there is a fix for the problem, and Developers may not know either. At least this is the impression I'm getting. If a switch model can be stacked then new versions that support the model should assume that the model will be used in a stack and support the stacked version as well. 

[TomMar1]

We had the same issue.  I deleted that switch from CER and added it again.  After running a discovery in CER it found all the ports in that 9300 stack.