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IP-MAC CONFLICT: Conflict in ip-mac binding between packet and snoop table data


The wireless on our AP-4511's keep going in and out. After checking the logs I see hundreds of ip-mac conflicts. For example:

Jan 26 15:57:29 192.168.3.177 2014-07-20T18: 52:30.%02u-04:00 ap4511-63DFFC %DATAPLANE-4-IPMACCONFLICT: IP-MAC CONFLICT: Conflict in ip-mac binding between packet and snoop table data : Vlan = 1, Pkt Src Mac: C0-BD-D1-26-56-29, Pkt Dst Mac: 00-04-96-52-36-EF, Pkt Dst IP : 192.168.10.3, Snoop Table Mac: 4C-EB-42-82-2C-CE, Snoop Table IP: 192.168.10.3 .

192.168.10.3 is our DNS server

The snoop table MAC is one of our laptops. That laptops network settings all check out. It still appears in the logs when I disable that NIC too. We have a master AP as a dhcp server.

What could be causing this? This one laptop seems to be the culprit, but it looks like it is preventing other machines from getting to the DNS.

1 reply

Userlevel 4
Where ever a static ip address is located, it has to be configured as a trusted port.
I always recommend configuring the ports of any AP into a trusted state.
All it takes is for someone to assign a static IP to a wireless NIC and the port is locked down
Been there, seen that
Jason Parker

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