Forum

Rog Escribi?3:

Anyone else having problems with other people's Cisco access points logging on the wrong controller?

I was talking to a customer of mine (who provides services to cable companies) who has that happen regularly, and I suspect that it's an issue related to Cisco's discovery.

Once they appear on someone else's controller, then you of course have the option of doing whatever you want to them. :)

A wired Cisco AP goes through a lengthy process to figure out which controller it should use. Under 4.x code, unless the AP and the controller are on the same subnet, the AP cannot join another controller without "external" help in locating the controller (unless it joined to that controller previously). The easiest way to ensure that (wired) Cisco APs connect to the proper controller is to use the DHCP Option 43 or DNS methods of telling AP's where to connect (see link below).

If the APs are wired APs, and they are connecting to the wrong controller (especially another company's controller), I would have to blame a poor network design. I'm not saying they are perfect, but the process is pretty consistent. The only problem I have seen is when APs connect to the "wrong" controller out of the 4 that I have running. APs sometimes get confused when you have failed their controller (for something like an upgrade), which forces them over to a secondary controller, and then brought the primary controller back online. I have seen an AP keep bouncing back and forth between the primary and secondary controller until you force the AP to reboot.

Good info and troubleshooting about the join process can be found on the Cisco wiki:

http://supportwiki.cisco.com/ViewWiki/index.php/Troubleshoot_a_Lightweight_Access_Point_Not_Joining_a_Wireless_LAN_Controller