View Current IP's address in Use?

[youngoz2002]

hey Guys

What commmand would I use to view the current IP addresses being use. I'm having a problem with IP address conflicting.Please note this is the fist time I'm working with a Cisco router. I have the proper access to get to the router. Thank You in Advnace

[gpulos]

there are a few ways to see what IP addresses a cisco router is aware of:

1) do a 'show arp' at the router prompt. (to view all arp entries the router has)

2) check the DHCP server if the router is running one with 'show dhcp server | lease | pool (to view any DHCP pools/leases the router is handling)

3) do a 'show ip interface' to get a list of interfaces running IP. (to view all interfaces, and their addresses, configured for IP)

[jackyoung]

You may also try to use some scan tool (not from Cisco) to scan the active IP in the network. Or write a script to ping the range.

[EugeneL]

If you are looking for ip addresses used for the router itself you can do

show ip interface brief

if you are looking for what addresses router sees you should look at arp table

show arp

Also consider looking at the logs , if you have logging configured. You may see something of value there