topic Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine in Wireless

1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

MatthewMattShenkoShenko — Mon, 03 Oct 2022 18:19:56 GMT

I've tried different channels and different channel widths.
I've looked at radar event counters, but they're not incrementing.
I've run my config through the wireless config checker.
Interference and noise aren't terrible and I have a terrific SNR.

Yet the 5ghz backhaul on my wireless bridge keeps dropping at least once an hour. If I switch to 2.4ghz, everything's fine. But slow.

Using two 1572EAC APs and a 9800-L WLC in a mesh bridge setup. One is root (RAP) and acts as parent, the other is mesh (MAP) and acts as child. Each AP has a directional AIR-ANT2588P3M-N= antennae with line of sight, about 150' apart.

When these 5ghz drops occur, the only error on the 9800 is "heartbeat timer expiry". The RAP registers the mesh neighbor going down, but shows no errors.
On the MAP, however, prior to each drop I'm seeing a consistent error like the examples below (each line is a separate drop event):

%DOT11-2-FAILURE_RADIO_RESET: Interface Dot11Radio1, reset due to FW: cmd=0x31 seq=6, @87D9E9B1,s@87D9E6DB(14)
%DOT11-2-FAILURE_RADIO_RESET: Interface Dot11Radio1, reset due to FW: cmd=0x31 seq=6, @54FE2A17,s@54FE290D(14)
%DOT11-2-FAILURE_RADIO_RESET: Interface Dot11Radio1, reset due to FW: cmd=0x16 seq=6, @A7713B02,s@A7713A91(14)
%DOT11-2-FAILURE_RADIO_RESET: Interface Dot11Radio1, reset due to FW: cmd=0x31 seq=6, @CD4BA8EB,s@CD4BA880(14)

In a lab setup everything worked OK, but when the time came to deploy for real, the above began occurring after a channel-width change. We've since tried putting all radio settings back to the way they were, but to no avail -- the drops persist.

If anyone has experienced anything similar or has any ideas for troubleshooting, please let me know ...

Thanks!

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Arshad Safrulla — Mon, 03 Oct 2022 21:02:38 GMT

Seen similar kind of error message in the same platform, TAC wanted us to upgrade from 16.12.X to 17.2 at that time which fixed the issue. Better reach out to TAC to identify the problem, but I recommend start from running the TAC recommended codes

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/214749-tac-recommended-ios-xe-builds-for-wirele.html

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Haydn Andrews — Mon, 03 Oct 2022 21:24:27 GMT

What WLC version you running. Had similar issues on 17.6 ended up on a engineering special

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Olamideharrison — Tue, 04 Oct 2022 01:21:50 GMT

Its easy to fix if you reach out to tac once the problem is identified im sure I can let you know how to get it fixed

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Rich R — Tue, 04 Oct 2022 16:16:55 GMT

Did you have a bug id for it @Haydn Andrews ? (so that we can work out which release(s) have the fix)

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Haydn Andrews — Tue, 04 Oct 2022 21:40:29 GMT

https://bst.cisco.com/quickview/bug/CSCwc55632

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

Rich R — Tue, 04 Oct 2022 23:38:51 GMT

Thanks @Haydn Andrews

So @MatthewMattShenkoShenko looks like you'll need to contact TAC as there's no public release with that fix yet.

Re: 1572EAC AP consistently drops 5ghz backhaul, but 2.4 ghz just fine

MatthewMattShenkoShenko — Wed, 09 Nov 2022 15:25:19 GMT

Thanks for the replies, all, esp @Haydn Andrews and @Arshad Safrulla

Recently upgraded to 17.3.6, and this resolved the issue. Software bug ... assumed I had configured something incorrectly. Drove me nuts.