Cisco SG300-20 Duplicate IP Address
Posted on 2014-04-22
I have a SG300-20 Switch in Layer 3 mode.
The switch IP, which is the gateway for VLAN 5 is 192.168.5.1
On Gi 3, a server on VLAN 5 is present. It has an IP of 192.168.5.241
On the switch, I receive the log entries of:
%IPADTBL-N-IPDUPLICATE: Duplicate IP address 192.168.5.1 from MAC a0:b3:cc:eb:f2:2d was detected on VLAN 5, port gi3
On Gi3 is a HP ML150 server. Only one of the two nic's connected. The MAC address of the NIC is A0-B3-CC-EB-F2-2A
It almost suggests to me that a sub address of the nic has the same ip as the default gateway. (MAC 2A instead of 2D)
I cannot find anywhere on the server to change or remove an ip configured for that MAC address. This is what I have done to troubleshoot:
I moved the connection to a different port on the switch, the dup went with the port change
I switched the physical connection from LAN 1 to LAN 2 on the server. Gave the second NIC the same IP Settings as the first (it is a production server after all so an IP change isn't so easy). Even changing the NIC didn't get rid of the duplicate message, the MAC did however change in the log on the duplicate to be the same as the new physical NIC, except once again changing the final character by a few.
So, i am at a loss. I have absolutely no issues on the network, everything works great. Everything finds the gateway properly. I just have a concern with this duplicate IP error message. It doesn't seem right to just accept such a logged note.
Anyone have any ideas how I can get rid of this message?