strange log entry on WLC5508?

[kreiwer]

following log entry on a WLC5508 (7.4.100.0) is permanentely filling up the log buffer and the WLC operates in low performance.

*spamApTask7: Oct 29 10:08:13.114: #LWAPP-3-DUP_AP_IP: spam_lrad.c:33673 Duplicate IP address detected for AP APb0fa.eb3d.8b4f, IP address of AP  0.2.146.0, this is a duplicate of IP on another machine (MAC address  4:ba:53:e0: 0: 0)

*spamApTask0: Oct 29 10:08:04.478: #LWAPP-3-DUP_AP_IP: spam_lrad.c:33673 Duplicate IP address detected for AP APb0fa.ebb8.de74, IP address of AP  0.2.146.0, this is a duplicate of IP on another machine (MAC address  4:b9:c8: 0: 0: 0)

*spamApTask7: Oct 29 10:07:43.113: #LWAPP-3-DUP_AP_IP: spam_lrad.c:33673 Duplicate IP address detected for AP APb0fa.eb3d.8b4f, IP address of AP  0.2.146.0, this is a duplicate of IP on another machine (MAC address  4:ba:53:e0: 0: 0)

*spamApTask0: Oct 29 10:07:34.477: #LWAPP-3-DUP_AP_IP: spam_lrad.c:33673 Duplicate IP address detected for AP APb0fa.ebb8.de74, IP address of AP  0.2.146.0, this is a duplicate of IP on another machine (MAC address  4:b9:c8: 0: 0: 0)

Has somebody an idea what the issue is or can be? Or has it been monitored from someone else on other installations as well?

Both AP's does have different IP adresses from DHCP server x.y.z.248 and x.y.z.249. WLC is working as internal DHCP server. DHCP proxy is disabled. From what could this strange address 0.2.146.0 come from? I've never seen such an address like 0.2.146.0

I would like to appriciate any kind of help or suggestions

thanks a lot

Klaus

[blenka]

This is another common issue that is seen when the AP tries to join the  WLC. You might see this error message when the AP tries to join the  controller.

     No more AP manager IP addresses remain

One of the reasons for this error message is when there is a duplicate  IP address on the network that matches the AP manager IP address. In  such a case, the LAP keeps power cycling and cannot join the controller.

The debugs will show that the WLC receives LWAPP discovery requests from  the APs and transmits a LWAPP discovery response to the APs. However,  WLCs do not receive LWAPP join requests from the APs.

In order to troubleshoot this issue, ping the AP manager from a wired  host on the same IP subnet as the AP manager. Then, check the ARP cache.  If a duplicate IP address is found, remove the device with the  duplicate IP address or change the IP address on the device so that it  has a unique IP address on the network.

The AP can then join the WLC.

[kreiwer]

Thanks very much for your suggestion.

Unfortunately it does not help. All installed AP's joined the controller and do

have indivdual IP addresses.

I did not found any duplicate IP address in ARP cache.

MAC address tables in the switches do also not shown this MAC

4:ba:53:e0: 0: 0 or this MAC 4:b9:c8: 0: 0: 0 from the WLC log.

No AP does have this strange address 0.2.146.0

Nevertheless this logmessage comes up in the WLC every 3rd second.

Very strange... Maybe there must be 2 clients attached to the network which does have this address

0.2.146.0 which I cannot found or it is a controller bug.

[kreiwer]

Issue has been solved by restarting both affected AP's. Still unclear how this issue could happen.

[yusuf habibi]

i think your AP isn't completely progress until join into wlc. sometime we need to restart AP's or unplug cable if connect with PoE. i have similar issue with this a few month ago.

Regards,

Habibi

[marce1000]

                  - FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCum06216

 M.

[Saurav Lodh]

However, the main reason is below

Error Message    %LWAPP-3-DUP_AP_IP: Duplicate IP address detected for AP [chars], IP 
address of AP  [chars], this is a duplicate of IP on another machine (MAC address 
[hex]:[hex]:[hex]:[hex]:[hex]:[hex]) 

Explanation    A duplicate IP address has been detected for the specified AP.

Recommended Action    Check the DHCP configuration and also change the IP address of the AP if it  was configured statically.

[azeemusman.mca@gmail.com]

Recommended Action: 

Verify in the network  if you have any devices which have the same IP address in the network.

Verify ARP entry from the core devices and see if you find two MACs for one IP.

Verify DHCP configuration & see if the same IP is reserved for any other devices. 

Try to search the mac address on your core switch using sh mac address-table address  [hex]:[hex]:[hex]:[hex]:[hex}:[hex]