%SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX-XXXX-XXXX from Port-channel1

[gary_the_network_guy]

We experienced Issues regarding network-connectivity, I looked into some loggs on our WLC 9800 and saw a bunch of loggs like this:

.Oct 11 15:51:27.768: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:224 TS:00001035332249163839 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.
.Oct 11 15:50:24.978: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:167 TS:00001035269455385994 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.
.Oct 11 15:49:20.263: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:209 TS:00001035204736854295 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.
.Oct 11 15:48:17.389: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:004 TS:00001035141859772682 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.
.Oct 11 15:47:15.594: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:216 TS:00001035080061157196 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.
.Oct 11 15:46:13.467: %IOSXE-4-PLATFORM: Chassis 2 R0/0: cpp_cp: QFP:0.0 Thread:094 TS:00001035017930663327 %SWPORT-4-MAC_CONFLICT: Dynamic mac XXXX.XXXX.XXXX from Port-channel1 conflict with WlClient, please check the network topology and make sure there is no loop.

The WLC is connected to our 4500 CoreSwitch, it is a vss configuration. Any Ideas?

[balaji.bandi]

WLC 9800 virtual or appliance ?

may be worth checking below bug if you are running the code mentioned in the bug :

https://quickview.cloudapps.cisco.com/quickview/bug/CSCvt96686

[gary_the_network_guy]

It is an appliance, but I think I know why it is happening. We have an old WLC 5508 running right now. Also the new WLC is running Version 17.3.5b. So the bug you mentioned should be already fixed.

[Rich R]

And why do you think it is happening?

[Arshad Safrulla · Accepted solution]

is all your AP's are in local mode?

• Are you in the middle of an migration from 5508 to 9800?
• Do you have some AP's registered in the 9800 and others in 5508 in one single roaming domain?
• In both 9800 and 5508 are you using the same VLAN to SSID mapping?

If yes I think then this is expected as this is a typical scenario when a client connected to and AP in 9800 moves to an AP in 5508 or vice versa.

[gary_the_network_guy]

You are absolutely right, I am in the middle of an migration(from 5508 to 9800) and also we use the same VLAN to SSID mappings.

After turning the AccessPoints from Flex to local mode, the port-flapping stopped. The WLC learned the mac from core and ap!