Moving APs between controllers

[KevinR99]

I have a test 2802 that I had previously attached to an AireOS controller.  v8.5 if I recall.  I then attached it as a test to a Cat9800v.  When I try to swing the AP back to the AireOS controller it just won't join.  I get errors related to unable to decode CAPWAP packet.

I tried to manually download the AireOS image from a TFTP server from the CLI and u-boot prompt but no success with either method.

Should I be able to move APs between different controller OS ?

Thank you for any input, Kev.

[Flavio Miranda]

Hi

 Try to run the command "clear capwap config" on the AP.  Reboot it and try again.

[KevinR99]

That command is not available.  However, I did try capwap ap erase all and reboot but still no success.

All I see on the AP is

Could not discover WLC

The WLC is on the same subnet and the AP also gets the WLC address from the DHCP server.  The WLC does get a discovery attempt but doesn't respond.  The WLC gives the following errors

Failed to decode discovery request from X.X.X.X:5256

State machine handler: Failed to process msg type = 1 state = 0 from X.X.X.X:5256

Failed to parse CAPWAP packet from X.X.X.X:5256

That port number 5256 seems strange.  I expect 5246 for CAPWAP control packets.

[Flavio Miranda]

cawpap port is 5246. Is there a Typo or something is wrong there?

[ammahend]

Should I be able to move APs between different controller OS ?

Yes you should be able to.

Since you already tried lot of things, can you also try hard reset of the AP using reset button ?

is there a firewall between AP and controller ?

is time set correctly on controller ?

attach the AP boot logs from AP console and capwap debugs from controller if you can.

[Haydn Andrews · Accepted solution]

can you confirm the following:

AP was originally joined to the AireOS WLC before migrating to 9800

AP when attempting to migrate back doesn't join same AireOS WLC

What exact versions are running on the AireOS and 9800 WLCs

Is the AP using the same Subnet to join both WLCs

How did you migrate between WLC (via static WLC commands?)

Can you post the boot log of the AP from its console port

If using 9800 17.6 check this bug https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvx98176 

As if you are not using 8.5.182.0 on the AireOS and using 17.6 on the 9800 you might have hit that

[KevinR99]

Haydn

Thank you for this.  I got the AP working but in a round about way.  I put 8.5.182 on the AireOS controller but the AP still wouldn’t move.  So I then put 17.5.1 on the IOS-XE controller and allowed the AP to downgrade.  It was at 17.7.1  Once the AP downgraded to 17.5.1 I managed to push it over to the AireOS controller and I can now freely move between AireOS 8.5.182 and IOS-XE 17.5.1

Thank you. Saved me an AP there.

Kev.