AP doesn't connect to WLC on new switch

[antonio-vazquez]

Hello everyone,

I need your help. I’m a beginner in networking and just started a new position.

I have an AP model C9120AXE-A, and when I try to connect it to a C9407R switch, the AP stays stuck in "finding WLC" mode. I’ve checked the AP logs, and it indicates it can’t find the WLC. However, when I connect it to a WS-C2950G-24-EI switch, the AP works perfectly.

Here’s what I’ve already tried:

Changing the interface speed
Switching the mode from trunk to access to see if it can find the WLC
Verifying that the new switch has communication with the WLC
Checking that the configurations are similar

I would really appreciate your guidance.

[Preston Chilcote]

First, see this helpful post to better understand the different methods an AP uses for "Controller Discovery".  DHCP option 43 is the one I've seen most often, so you'll want to see in the AP logs if it's getting DHCP offers from the DHCP server.

https://community.cisco.com/t5/wireless/controller-discovery-and-ap-states/td-p/3887250

You'll also want to look into which vlan the WLC is on and that all the switches have access to that vlan so traffic can get from AP to WLC once the WLC IP is known. 

[Leo Laohoo]

Console into the AP and post the entire process.

[ilay]

Is the IP address obtained by the AP when connected to the 9407 different from the one obtained when connected to the 2950?

Try using `show capwap client config` to verify the AP's configuration.

If the WLC settings are not visible, you can manually configure the WLC address using either:`capwap ap controller ip address x.x.x.x` or `capwap ap primary-base WLC-NAME x.x.x.x.`