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Cisco WLAN Controller - IP address being used by another machine

In troubleshooting some sporadic connectivity issues at our new office, I noticed some unusual event traps in the log today.

This is a small wireless network with a single Cisco WLC-2504 controller and 4 APs.  There are fewer than 15 wireless devices connected at any given time.  It seems that two of the APs are showing traps every minute or so, similar to these:

Tue Sep 17 15:26:16 2013 Warning: AP with Base Radio MAC d4:8c:b5:61:11:92 has found its IP Address being used by a machine with MAC Address 02:13:f5:70:00:00.

Tue Sep 17 15:26:05 2013 Warning: AP with Base Radio MAC 44:03:a7:f1:d4:82 has found its IP Address being used by a machine with MAC Address 08:21:c8:20:00:00.

This seems to be interfering with connectivity for the wireless clients attached to these APs as well, causing brief disconnects.

What I find interesting is that the IP addresses listed in the traps ( and are not in any way present on our network.

Any ideas or suggestions on how I can troubleshoot and resolve these errors?
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1 Solution
Is LAG enabled on the controller & you've connected more than one port from your controller to different switches?
gwermterAuthor Commented:
No, but I think I've found the problem. Both of those access points show the same static IP. The trap message is misleading, but I'd essentially correct in that there is an ip conflict. Changed duplicate IP and have begun testing.
Craig BeckCommented:
Yep it's as simple as a duplicate IP.
gwermterAuthor Commented:
After testing, the duplicate ip address on the access point was the issue and fixing it resolved the problem.
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