No Wi-Fi service after site power outage

[Anonymous]

Remote site, v2110 controller with 20 AP3912i's, LAN running on X440G2's.
No Wi-Fi service after site power outage.  😞
I had to reboot the controller twice to get a working GUI, but the status page shows all APs as being inactive/down.
Disabled and re-enabled inline power to APs on X440G2s, but they're not coming back online.
They do get an IP from the DHCP server, but don't answer to ping requests.
On the switch, they do show up in the FDB, but don't show up in the ARP table after trying to ping them.
LLDP info sent to the switch looks fine, complete with IP address.
What could possibly have gone wrong?

[Gareth_Mitchell]

Hi Nicolas

It's hard to say without more information, you could connect a cable to the serial port on the AP and do: cat /tmp/log/ap.log;tlog

Perhaps a port mirror of 1 AP to capture any traffic might be useful.

Open a case with GTAC and we can take a look.

-Gareth

[Anonymous]

Hello Gareth,

Connecting to the AP serial port was not really feasible with no onsite IT staff, but thanks for the suggestion.
Port mirroring was also not going to be easy.

Anyway, it ended up being a Windows DHCP server problem.
It seemed to behave normally, updated leases and so on, but devices were NOT getting their IP.
Seems like the DHCP request was only partly handled.
What really made it difficult to diagnose (remotely, again) it that APs did report their IP over LLDP, but were not actually using it.

Fixed now, thanks for your help.

Nicolas