AP backup tunnel not establishing

[Andre_Brits_Kan]

Hi Community

We have two C5210 Controllers configured in a High Availability cluster.
The solution is configured as a Primary/Backup solution, with all the AP's homing to the first controller as the primary and the secondary as the backup.

We have just over 600 AP's.

On the second controller we see the following error for random AP's.
 

The AP can reach both controller so this is not a routing error as refered to in the below post:
https://extremeportal.force.com/ExtrArticleDetail?an=000064655

Any ideas?

Regards

[Tony1]

We have the same problem. In the past a reboot of the Controller solved it.
Reboot, power cycle of the APs and factory default do not fix the problem. I will open a GTAC case.

Problem seems not be related to routing or firewall rules. We have some IP networks with APs that have backup tunnel and APs that do not have a backup tunnel.

It looks like this problem appears after some uptime of the Controller and then does primarily affect new access points.

[Nathiya_Munuswa]

Hi Andre,

Please check the High Availability Pre-requisites for your reference,

https://extremeportal.force.com/ExtrArticleDetail?an=000082528

Regards,
Nathiya M

[Ronald_Dvorak]

As Jermey mentioned it's either after a software upgrade during the first authentication - will fix itself within minutes - or if "normal" availability is configured and the AP lost the connection to the home controller but the controller-controller link is still up = FAD.

[Jeremy_Gibbs]

When I have seen this, often a cset factory on the AP will do the trick. But it's not all of the APs. It's usually only a few that went "crazy" after applying an update.