How can I find a particular IP address ?

[coupleojars]

I have a network made up of a 6506 core and a number of 3548 XL switches. I have reserved a number of IP addresses for a special project but have found that one of the addresses is being used. Is there a command to look up what port on what switch this device is connected to ??? I have established that it is not a server ( as it doesn't have a hostname) , an HP device ( as it doesn't come up via HPJetdirect ) or a cisco device.
Any contributions much appreciated,

MM

 

[bobthecat]

HI M, telnet to the router and get the mac address of the device eg. sh ip arp 140.4.?.? whatever the ip is.
The router will give you the a mac address associated with that IP, something like 0050.8bd7.a8e4.
then telnet to your switch and enter, sh cam 00-50-8b-d7-a8-e4 this will show you the port the device is connected to.
If you have many switches that are trunked together it may show you the trunk where that mac will be found, if telnet to the next switch on that trunk.
sorry for the rushed reply

Bob^^

 

[sobak]

If you are working from a Windows NT(2000) workstation ping the address. Once the reply's are completed type in arp -a This will give you the MAC address of the IP Address (you will need to pick it out of the list). Then log into one of your switches and then type in. sho mac-address-table this will give you all the MAC addresses known to the switch and what port they are on. I used this to track down a windows workstation that was unauthroized on my network, once I found the port number I shut it down. Hope this helps, of course there may be an easier way but this is the only way I know.

david e
*end users are just like computers, some you can work with...others just need a simple reBOOTing to fix their problems.*

 

[RouterGod]

Following with the idea sobak used, alternatively you could type SHOW CAM MAC-ADDRESS (where MAC-ADDRESS is the MAC of the station seperated by hypens). This will show you all the details of the MAC including the blade and port (interface) it's connected to. Regards,

Don