switch CPU MAC addresses

just wanted some clarification on this one.

Are all the CPU MAC addresses that are show as CPU in the 'show mac-address-table' command unique to the switch?

when I do this command on my 3550 it has 48 CPU mac addresses and when I do it on the 2950 it has none but under 'show int vlan 1' it has a MAC address, is this it's sole address?

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Comments

Netwurk

Command varies from one model to another and of course your IOS version has an effect too.

Your 48 addresses from your 3550 are one for each port. They are shown as STATIC on most models. You might also see a reference to BIA (burnt in address) on other commands. This also refers to these MACs.

aueddonline

Netwurk wrote:

Command varies from one model to another and of course your IOS version has an effect too.

Your 48 addresses from your 3550 are one for each port. They are shown as STATIC on most models. You might also see a reference to BIA (burnt in address) on other commands. This also refers to these MACs.

my 3550 only has 24 ports, so is that 2 for each

Netwurk

aueddonline wrote:

my 3550 only has 24 ports, so is that 2 for each

Good point. There's also some 0100 and 0180 STATIC entries, they're reserved. Don't ask me for what.

Let's see. 24 ports.

Your first STATIC should be the master one for the switch. Do a show int VLAN 1 to confirm this. The next 24 should be your ports. And you may have two more if you have the two GBIC slots.

aueddonline

Netwurk wrote:

aueddonline wrote:

my 3550 only has 24 ports, so is that 2 for each

Good point. There's also some 0100 and 0180 STATIC entries, they're reserved. Don't ask me for what.

Let's see. 24 ports.

Your first STATIC should be the master one for the switch. Do a show int VLAN 1 to confirm this. The next 24 should be your ports. And you may have two more if you have the two GBIC slots.

yeah got a couple of GBIC slots, yeah the first is the primary, the next 24 are ports f0/1-24, next two are the 2 GBIC and then they start on the 0100's

cool, all those make sense now.