I have a 3550 Catalyst Switch. 2 computers connected to the switch have the same IP address configured and there is an IP address conflict. How do i zero in on these computers with just the CLI of the switch?
Generally an IP address conflict is logged. Do "show log". You will see something like
Duplicate address 10.25.32.15 on Vlan25 sourced by 0011.2233.4455 and there will be another message with the other mac address.
Then you show the mac address-table to see what port that mac address is connected to. (
show mac-address-table address 0011.2233.4455 )
As far as I know there is no straight solution for this. In your case you can create a MAC address based ACL and bind it to the VLAN in which those SwitchPort exist. Of the two MAC address block one. Detection of the problem this way will be quick with a little obstruction in network service. You can refer to this configuration from Cisco doc.
There are a few ways to do this. Is your switch running layer-3? If it is, then you can review the arp table on the switch for duplicate entries. You can also turn on ip tracking on the switch and then go through that data.
You will need to enable ip tracking first: ip device tracking You can then use: show ip device tracking all. Instead of using all you can enter an interface or an ip address to show these commands.
ravi babu .. the best way to clear the ip conflict ,if DHCP is enabled in your network just give ipconfig /release and ipconfig/renew in both the pcs . If you gave static ip in your both the pcs .. then go to network settings and change the ip on both pcs. I don't think in the switch you can achieve this ,unless you have to shutdown any one of the switch port.