CIsco 9800 WLC: Failed to dot11

[jacovr]

I am busy troubleshooting an intermittent issue on my wireless network, on the 5GHz network.

When I look at the Radio Active traces, I do not see any "real issues" that stand out, however I do so quite a lot of these errors below, but do not seem to find anything on the internet.   Nor do I see if this is actually causing issues.

2022/09/29 11:55:48.344096 {wncd_x_R0-0}{1}: [dot11] [18116]: (info): Failed to dot11 map external to internal ie type. Unsupported IE received, skip decode . IE Type :199
2022/09/29 11:55:48.344097 {wncd_x_R0-0}{1}: [dot11] [18116]: (info): Failed to dot11 get vendor specific id. Wrong vendor ie Type(4) received2022/09/29 11:55:48.344098 {wncd_x_R0-0}{1}: [dot11] [18116]: (info): Failed to dot11 get vendor specific id. Wrong vendor ie Type(2) received

Any help will be appreciated.

[marce1000]

 - Note that you can have Radioactive client Trace(s) analyzed with : https://cway.cisco.com/tools/WirelessDebugAnalyzer/ , also have a checkup (validate) of the 9800 WLC with the CLI command : show  tech   wireless , have the output analyzed by  https://cway.cisco.com/tools/WirelessAnalyzer/  , please note do not use classical show tech-support (short version) , use the command denoted in green for Wireless Analyzer.               Checkout all advisories!

  Look into the current software version being used on the 9800 WLC versus https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/214749-tac-recommended-ios-xe-builds-for-wirele.html

  If ISE is being used as an authenticating environment then review this document for guidelines : https://community.cisco.com/t5/security-knowledge-base/ise-and-catalyst-9800-series-integration-guide/ta-p/3753060#toc-hId--1620733215

                       Make sure client wireless drivers are up to date (too)

 M.

[Ashok09]

I too have this problem 
Cause of this Frequent Wi-Fi Disconnection
Failed to dot11 map external to internal ie type. Unsupported IE received, skip decode . IE Type :59

[marce1000]

 - @Ashok09 
                                FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwd73744

 M.

[Ashok09]

Thank you Marce, But after reauthentication also facing same issue.  

[marce1000]

@Ashok09 
   - Use latest advisory software version on the 9800

 M.

[Ashok09]

Hi @marce1000 
yes I also thinking the same. Currently running in version 17.03.05b. Raised TAC team support to suggest the latest IOS which should be support both 1850 and 9115 APs

[JPavonM]

As 17.6 is running EoS in short (https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/ios-xe-17/ios-xe-17-6-x-eol.html) move to the next long-term release which is 17.9.

TAC receommended release for 17.9 train is 17.9.4a APSP6 (https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/214749-tac-recommended-ios-xe-builds-for-wirele.html#toc-hId-2052757410)

[JPavonM]

Which type of client is that? (device type, OS version, driver/firmware)

And which type of L2 security have you implemented on the WLAN? (WPA2, WPA3, WPA3 transition, FT/OKC,...)

[Ashok09]

Hi

dot1X authentication, all windows clients 

[JPavonM]

Are you using SHA256 AKM?

If so, there is a known behaviour impacting roaming and disconnections with that on Windows 10.