WLC 2112 - APs disassociating

[matt.millington]

I've found some discussion on this, but nothing that's helped resolve so I'm hoping someone can help. We recently purchased a 2112 WLC, running version 6.0.199.4. I have everything running through a single port on the controller, which is connected to a trunk port on our 3750 stack. Our management VLAN is vlan 40, and AP is plugged into another port on the same switch which is an access port in vlan 40. APs appear in the controller ok, receive an IP address, but we aren't able to connect to any of the WLANs and periodically the APs will disassociate with the following messages:

0	Thu Mar 22 09:47:51 2012	AP 'AP003a.99eb.702d', MAC: b8:62:1f:45:95:b0 disassociated previously due to AP Reset. Uptime: 0 days, 00 h 35 m 52 s . Last reset reason: operator changed 11g mode
1	Thu Mar 22 09:47:39 2012	AP Disassociated. Base Radio MAC:b8:62:1f:45:95:b0
2	Thu Mar 22 09:47:39 2012	AP's Interface:0(802.11b) Operation State Down: Base Radio MAC:b8:62:1f:45:95:b0 Cause=New Discovery

I'm not sure if that's related to why we can't connect to the WLANs or not...

Another wrinkle is that if we plug in the AP directly to one of the PoE ports on the controller, it all works perfectly. Any ideas? I'm guessing its something switch-related since the only difference is that we're not going through the switch when it works.

Thanks in advance,

Matt

[Scott Fella]

What model AP's by chance... if they are the 3500's, you need to run 7.0

[matt.millington]

1142s

[Scott Fella]

Okay... Well look at upgrading to 7.0.230.0. Any who... You certain you don't have another device using the same address as the ap-manager? If you disconnect the wlc from the network, can you make sure the ip address you used are not pingable?

Thanks,

Scott Fella

Sent from my iPhone

[matt.millington]

Its not pingable when the WLC is disconnected. Neither is the management IP. If I ping those IPs from another network, I have great connectivity. No apparent issues at all. Only with the APs.

I will say this, sometimes when just navigating the WLC's web interface (or via CLI), it can get really slow almost unresponsive. I'm not sure if that's because of the constant rediscoveries, or issues talking to the APs or not. I'm going to debug some on the WLC and see what I see.

[Scott Fella]

So the port the WLC is connected to negotiates fine at 100 full?  On the WLC for the management, ap-manager and wlans, you have port 1 as primary and the backup set to '0'?

[matt.millington]

Yes, it negotiates to 100Full. There are some runts on the switchport, but I don't know how old they are. They haven't incremented at all today. Otherwise, switchport looks good.

I have everything (managment, ap-manager, and WLANs) on port 1 of the WLC. I don't have a backup set at all. Not sure how to do that...

[Scott Fella]

Don't worry about the backups until you can get these aps to join.  Are these ap's new or converted?

[matt.millington]

OK. These are brand new APs, not converted. They join, then they "unjoin" and have to rejoin, but even when they show as joined, we can't connect to any of the WLANs.

Could it be DHCP option 43-related? I was a little questionable on that setup, but I figured that since the APs found the WLC and joined, it must have been set up correctly. I followed the Cisco instructions exactly...

[Scott Fella]

You don't need option 43 nor DNS since the AP's and WLC are on the same subnet. Upgrade to either 6.0.x MD or 7.0.230.0

Thanks,

Scott Fella

Sent from my iPhone

[matt.millington]

So, after calling TAC, the fix ended up being to go into the Advanced tab on the wireless section of the controller and check the box for Pre-standard 802.3af switches as the source of power. By default, both that box and the Power Injector box were unchecked, and the switches are Cisco 3750s, so I'm not sure exactly why that worked. Do those switches not run standard 802.3af power?

[Kayle Miller]

Matt,

   This maybe a long shot but do you have multiple controllers?  If so are any of them setup as a master controller??  I have seen something similar happen when 2 WLC's were both set as master.

If all else fails try setting your only controller as a master and see if the behavior changes..

Hope this help.

[matt.millington]

Thanks Kayle. I'll try that tomorrow.

Scott, thank you so much for your time and efforts. I upgraded to 7.0.230.0 and have the same symptoms, though the error messages in the WLC logs are different now. They now say that the radio is disabled, but the APs still keep disassociating for some reason, but they work perfectly when the AP is plugged into the WLC directly.

I'm definitely lost. I opened a TAC case tonight.

-Matt

[Scott Fella]

Well keep us posted so others can know what the fix was.

Thanks,

Scott Fella

Sent from my iPhone