Tracing the Public IP from Cisco switch?

[Talha]

Good day all,

I have a scenario where we have a pool of 32 public IP which we allocated to few clients and they are using them on there network devices. All clients are connected using our 3750 switch. My issue is one client was assigned an IP and everything was working fine until someone within our network used one of the existing allocated IP and it has started connectivity continuity issues. Well we end up assigning another IP for moment to the effected client. Although I blocked that IP to send traffic from our network but I can still ping the IP. Is there any way I can trace our switch port where this network device with that particular ip is connected?

Thanks!

[chrihussey · Accepted solution]

Find the mac address of the device by checking the ARP table on the gateway router (show ip arp | i xxx.xxx.xxx.xxx (ip address), then identify the port on the switch by using the "show mac address-table | i xxxx.xxxx.xxxx" where xxxx.xxxx.xxxx is the MAC.

Hope this helps

[Talha]

Hi Chrihussey,

Thanks for the response. 

Sorry ignore my first reply as I was doing it wrong on my end, I found the port from your suggestion thanks