All the wireless access points suddenly dropped

[Max5]

Hi all,

Recently encountered a problem, the AP will suddenly be collectively disconnected, and the controller cannot be managed by logging in to the web. At the beginning, it took about 1 hour to complete the ap registration. Now the registration is completed automatically in about 10 minutes. It appears once a week on average, and it has appeared nearly seven or eight times so far.
There are more than 40 APs, some of which are older models, 1200, 1400, 1600, and the controller is 2504.
The following is the log record of the most recent failure. Someone reported that there was no network at 11:40 on August 3, and related screenshots at that time.192.168.52.52 is the AC management address. There are many types of error records in the log.

The important point is that wireless and wired share the same switch and divide different VLANs. When the AP is disconnected, it is normal for the wired network.

Can you help us find out what causes all APs to be offline collectively?

Sorry for everyone. I'm so busy that I forgot to reply.
In fact, we didn't do anything except reclassify all APs into a new VLAN, and the AC management address did not change.

As for the reason is still unclear, it may be related to the confusion of VLAN management of access layer switch.

 -----at  24 September 2020.

[Leo Laohoo]

*Jul 31 05:55:06.875: %LWAPP-3-CLIENTERRORLOG: Save LWAPP Config: error saving config file

What firmware is the controller running on?  

[Max5]

software version 8.2.151.0,field recover image version7.6.101.1

[Scott Fella]

You have a mix of AP’s and some that are very old. You are stuck on a version that would be very old and of course not supported. Here is the tac recommended version:
AireOS 8.2

For deployments that require features or hardware introduced after 8.0, TAC supports 8.2.170.0. No further 8.2 releases are planned.

If you have two 2504’s, you should move all the aps to the other one and see if that solves the issue or not. Don’t really know how to help you since the logs don’t always point to why. What have you done so far to troubleshoot and there were no network changes prior to the start of this happening?

[Leo Laohoo]

Agree with @Scott Fella and update the firmware of the WLC.

[marce1000 · Accepted solution]

 - Looks like you may have some sort of storm broadcasting issue (e.g.) at times. Have a setup in place where network traffic can be monitored and reviewed constantly.

 M.