topic Arrghhh aparently I was in Wireless

Old 4402s reporting its own MAC address in duplicated IP log.

Thomas Obbekaer Thomsen — Mon, 05 Jul 2021 11:18:31 GMT

Both 4402 has all of a sudden started to output this message:

"Warning: Controller has detected its IP Address 10.75.86.16 being used by a machine with MAC Address 00:0b:85:46:1e:c7."

The trouble is MAC address 00:0b:85:46:1e:c7 is the controllers OWN address ??!?!?

10.75.86.16 is the management interface of the WLC. (.15 AP manager).

The other controller has a similar message in its log, just containing its IP .14 and its own MAC address. (.13 AP manager)

At the same time APs starts to disconnect from the WLC.

Any suggestions ?

We have disabled one port of on each WLC in case it was some kind of LAG / Portchannel problem.

But still nothing.

The controllers had a fine uptime of a couple of years, and nothing like this has happend before.

We have tried rebooting and also upgarded to the newest 7.0.252 but still the problem exists.

Thomas Obbekaer Thomsen — Wed, 25 Nov 2015 19:20:43 GMT

Hmmm when we disable LAG on the WLCs the error never returns in the log.

(This is still with only one port connected from the WLCs to the switch)

APs are still disconnected after a short while 😕

Of course now the WLC has a different MAC address - Hmmmmm clear arp somthing on a switch ?

Thomas Obbekaer Thomsen — Wed, 25 Nov 2015 20:23:20 GMT

Arrghhh aparently I was hitting two errors.

MAC address AND the primary WLCs certificate had run out 😞

So all APs joined WLC 2 (this WLC has a newer manufacturing date) after being denied on WLC 1 - AP Fallback was enabled on WLC2, ... sooo ... 🙂

Still no word on the MAC address problem. Workaround was to disable LAG on the WLCs.