MAC addressing

geezer

Hi

Just want to clear a point up. On a switched network with multiple switches what steps/commands would efficiently obtain MAC to IP mappings especially if the host is on a remote switch? I know of the show arp to display local arp table but anything else I could use?

TIA

dtlokee

Show arp will give you the mac to ip address mappings, along with that you have show mac-address-table to see what interface has learned what mac addresses.

geezer

Thanks for that. I used the sh mac-address-table address xxxx.xxxx.xxxx mac address which showed the Vlan, MAC and Type as Dynamic. Would there be no way to show the IP address associated with this MAC or am I missing a point here?

Thanks again.

dtlokee

The mac-address-table doesn't keep track of the L3 information, only the L2 information, VLAN and MAC address mostly.

geezer

Thanks. Would there be anyway of knowing a remote MAC address say if pinging an address?

dtlokee

What I use sometimes is a ping sweep of a subnet on my PC then use a "arp -a" on Windows to find what entries are in the arp table, then compare them to the output of a "show mac-address-table". There are better tools for this but this is a low tech method.