DTLS session closed for AP, cause: DTLS server session error

annah1 · ‎08-01-2023

Hello ,

I have several APs getting dropped from wlc 9800 ( version : 17.3.6 ) with the error message : DTLS session closed for AP, cause: DTLS server session error

could you please advise what could be the problem

marce1000 · ‎08-01-2023

- Have a checkup of the 9800 controller configuration with the CLI command show tech wireless ; feed the output into : https://cway.cisco.com/wireless-config-analyzer/
Do this first!

Further on use these tools for troubleshooting AP join issues :
https://logadvisor.cisco.com/logadvisor/wireless/9800/9800APJoin

M.

-- Each morning when I wake up and look into the mirror I always say ' Why am I so brilliant ? '
When the mirror will then always repond to me with ' The only thing that exceeds your brilliance is your beauty! '

annah1 · ‎08-01-2023

Thank you @marce1000 for your feedback , i tried to upload the file to https://cway.cisco.com/wireless-config-analyzer/ , but i got the same initial page ( see attachement ) .

the file is in txt format .

marce1000 · ‎08-01-2023

- It should work , remember to use the CLI command show tech wireless ; not simple show tech

M.

-- Each morning when I wake up and look into the mirror I always say ' Why am I so brilliant ? '
When the mirror will then always repond to me with ' The only thing that exceeds your brilliance is your beauty! '

Rich R · ‎08-02-2023

And think about upgrading to 17.9.4.

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TAC recommended codes for AireOS WLC's and TAC recommended codes for 9800 WLC's
Best Practices for AireOS WLC's, Best Practices for 9800 WLC's and Cisco Wireless compatibility matrix
Check your 9800 WLC config with Wireless Config Analyzer using "show tech wireless" output or "config paging disable" then "show run-config" output on AireOS and use Wireless Debug Analyzer to analyze your WLC client debugs
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