topic Re: C9120AX-C Not able to join 9800 WLC in Wireless

C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Tue, 26 Dec 2023 00:22:05 GMT

C9120AX-C was previously joined to the controller, but for some reason it stopped working. Upon checking it disappeared from the controller. The last join attempt stats below

Re: C9120AX-C Not able to join 9800 WLC

Leo Laohoo — Tue, 26 Dec 2023 00:26:16 GMT

What firmware is the WLC on?

What is date of manufacture of the AP?

Re: C9120AX-C Not able to join 9800 WLC

Scott Fella — Tue, 26 Dec 2023 02:07:28 GMT

It’s easy if you take a look at this guide and other guides about AP troubleshooting. Also, if you console into the ap and reboot it, that usually will provide information on what is happening.
https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/218396-troubleshoot-catalyst-9800-ap-join-or-di.html

Re: C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Wed, 27 Dec 2023 07:42:09 GMT

Hi Leo AP image version 17.9.3.50 Controller 17.9.3.50

Re: C9120AX-C Not able to join 9800 WLC

Leo Laohoo — Wed, 27 Dec 2023 09:47:42 GMT

Factory-reset the AP, plug a console cable into the AP and reboot the AP.

Dump the boot-up process.

Re: C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Thu, 28 Dec 2023 02:16:37 GMT

attached logs when I restarted capwap for the AP

Re: C9120AX-C Not able to join 9800 WLC

Leo Laohoo — Thu, 28 Dec 2023 04:36:42 GMT

@Chrioni Siakla wrote:

Dec 28 02:10:37 kernel: [*12/28/2023 12:10:37.0011] AP has joined controller WLC

It says the AP has successfully joined the controller.

@Chrioni Siakla wrote:

Dec 28 02:10:53 kernel: [*12/28/2023 12:10:53.9882] Max retransmission count exceeded, going back to DISCOVER mode.

However, 16 seconds later, the AP drops out.

Please describe the network? Start with the description of the network where the AP is connected to?

Re: C9120AX-C Not able to join 9800 WLC

Rich R — Thu, 04 Jan 2024 17:48:57 GMT

Upgrade the WLC as per the TAC recommended link below. Currently: Cisco recommends 17.9.4 + SMU_CSCwh87343 + APSP (as needed) OR 17.9.4a + APSP(as needed) for all deployments.

Make sure you install the latest SMUs and APSP.

Re: C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Fri, 09 Feb 2024 01:45:24 GMT

few of the C9120AX-C previously joined and working then cant join the WLC anymore, I am still able to SSH into the WAPs

Re: C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Fri, 09 Feb 2024 01:46:52 GMT

have factory reset and same result

Re: C9120AX-C Not able to join 9800 WLC

Rich R — Sun, 11 Feb 2024 17:04:00 GMT

You might want to try 17.9.5 which was released last week - it includes fixes for both these bugs which might be related to your issue:

CSCwh61011

Cisco Catalyst 9120 and 9115 APs unexpectedly disjoins from the controller and does not establish DTLS again.

CSCwi04855

APs disjoin from the controller repeatedly with traceback logs.

Re: C9120AX-C Not able to join 9800 WLC

Leo Laohoo — Sun, 11 Feb 2024 22:23:31 GMT

CSCwi88967 (AP9120 randomly disconnecting from the WLC running S/W version 17.9.5.42) is a bit "confusing". Title says 17.9.5 but Known Affected Version says 17.9.4.

Re: C9120AX-C Not able to join 9800 WLC

Chrioni Siakla — Tue, 19 Mar 2024 10:54:36 GMT

We've fixed this issue upgrading from 17.9.3.50 to 17.9.4a (Cisco recommend at this as a stable version ).

Re: C9120AX-C Not able to join 9800 WLC

Samuele Leardini — Tue, 05 Nov 2024 11:39:20 GMT

Hi Chrioni, when you had the AP join issue, were your APs on Local mode or Flexconnect mode?

Thanks
Samuele