Layer 3 switch... find mac given IP
mikearama
Member Posts: 749
in CCNA & CCENT
Hey techies... I'm drawing a blank here.
I know an IP of a remote PC, and I'd like to determine the port it's connected to. The remote switch is layer 2, while my core is layer 3 4506's.
What's the command on my Cat's to find the mac addy, since I know the IP?
Much obliged,
Mike
I know an IP of a remote PC, and I'd like to determine the port it's connected to. The remote switch is layer 2, while my core is layer 3 4506's.
What's the command on my Cat's to find the mac addy, since I know the IP?
Much obliged,
Mike
There are only 10 kinds of people... those who understand binary, and those that don't.
CCIE Studies: Written passed: Jan 21/12 Lab Prep: Hours reading: 385. Hours labbing: 110
Taking a time-out to add the CCVP. Capitalizing on a current IPT pilot project.
CCIE Studies: Written passed: Jan 21/12 Lab Prep: Hours reading: 385. Hours labbing: 110
Taking a time-out to add the CCVP. Capitalizing on a current IPT pilot project.
Comments
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keenon
Member Posts: 1,922 ■■■■□□□□□□
sh ip arp
then you can track the device to the switch, then port its connected toBecome the stainless steel sharp knife in a drawer full of rusty spoons -
mikearama
Member Posts: 749
Brilliant... thanks.There are only 10 kinds of people... those who understand binary, and those that don't.
CCIE Studies: Written passed: Jan 21/12 Lab Prep: Hours reading: 385. Hours labbing: 110
Taking a time-out to add the CCVP. Capitalizing on a current IPT pilot project. -
Rearden
Member Posts: 222
Just for reference for people that want specific steps. . .
first ping the device from a router with an interface in that subnet, then do
show arp | include <ip address>
to get the mac address. then do
show mac-address-table | include <mac address>
to find out what port on your router or core switch it is out of. You need to do this until you track it down to which access layer switch it's on and then finally which port on the access switch. After you get past the layer 3 devices, just start with 'show mac-address-table'. Also, remember Cisco mac format aaaa.bbbb.cccc is different than 3Com and other vendors (aa-bb-cc-dd-ee-ff)More systems have been wiped out by admins than any cracker could do in a lifetime.