I’ve been having one hell of a time with a Cisco AP in one of our remote offices. Randomly, it will just fall off the face of the Earth and lose connection with our Controller at HQ. It started off as one of those mysterious issues where the cliche “reboot” would do the trick. While this may be okay for the first time it gets quite annoying if you have to do it multiple times thereafter.
Even TAC had a shot at it and while I can’t remember what they did the end result was still the same. I connected to the AP using a console cable to see if there were any log messages displaying. Yes there were!
Here’s what caught my eye:
AP resolving cisco-lwapp-controller to 10.39.39.19
Not okay with me because our controller is not located at 10.39.39.19. I know I specifically created a DNS entry for cisco-lwapp-controller and it was there. But why on Earth would it resolve to 10.39.39.19? I found that it was resolving the controller to cisco-lwapp-controller.cisco.com.
What I decided to do is manually set the configuration for the AP since it wasn’t getting the correct settings. I started by removing the ip helper-address on vlan with the AP. Then on the controller I performed the commands:
configured static ip addr to RemoteAP
config ap static-ip add domain RemoteAP localdomain.com
config ap static-ip add nameserver RemoteAP 126.96.36.199
Then verify settings on controller:
show ap config general ap-name