Duplicate address issue ...

[InternetB]

Hi,

I am getting this error message on a switch ...

Jul 24 01:07:02 CST: %IP-4-DUPADDR: Duplicate address 192.100.0.1 on Vlan10, sourced by 001a.6409.b212

Jul 24 01:08:07 CST: %IP-4-DUPADDR: Duplicate address 192.100.0.1 on Vlan10, sourced by 001a.6409.b210

Jul 24 01:09:10 CST: %IP-4-DUPADDR: Duplicate address 192.100.0.1 on Vlan10, sourced by 001a.6423.a7b4

This IP is the SVI of the switch. The issue I am facing that the mac address keeps on changing and therefore I am not able to solve this issue.

How would I be able to solve this duplicate IP address issue ....

Pls advice,

Cheers,

- InternetB -

[dhananjoy chowdhury]

From the MAC addresses it shows that these are some IBM devices.

The below command will show from which port it is coming.

"show show mac-address-table dynamic vlan 10"

[Goutam Sanyal]

Hi, As per cisco: Another system is using your IP address and Recommended Action: Change the IP address of one of the two systems. Additionally we found the same log at our LAN Network when switching loops had occurred. Conform that your network is loop free. Also if you have configured "HSRP", please check the entire configuration. Thanks Goutam. [pls rate if it helps]

[ahmed.yacoob]

The issue here is some user in the network made a mistake and write his IP address as the gateway.

To solve this issue you must know who's this user by show arp | inc (the mac address that is shown) then the ip will appear.

show mac-address-table add (the mac address that is shown) and you will find the port that which user assigned his IP as the gateway(interface vlan ip)

Regards