Interface details

RUN-DMC

Hardware is MCI Ethernet, address is aa00.0400.0134 (via 0000.0c00.4369)

Is the statement via 0000.0c00.4369 the base MAC of the router?

thanks for your inputs!

lwwarner

Check your output again. I think you'll find that it says (bia 0000.0c00.4369) not (via 0000.0c00.4369). As in "Burned In Address". Normally this matches the current MAC address. Have you used the mac-address command to manually change the MAC address?

R1(config)#int fa0/0
R1(config-if)#mac-address 11.22.33
R1(config-if)#^Z
R1#
*Mar  2 08:39:22.899: %SYS-5-CONFIG_I: Configured from console by console  
R1#sh int fa0/0
FastEthernet0/0 is up, line protocol is down 
  Hardware is AmdFE, address is 0011.0022.0033 (bia 0008.a3c0.5140)

jelexy

ardware is MCI Ethernet, address is aa00.0400.0134 (via 0000.0c00.4369)

your mac address is : aa00.0400.0134 not the one in bracket

RUN-DMC

lw- that was copied and pasted from cisco. check it here about 3/4 down.

http://www.cisco.com/univercd/cc/td/doc/cisintwk/itg_v1/tr1904.htm

i haven;t check on my devices but will do.


thanks guys

lwwarner

Ah, I thought you were asking about a real config. Well, that just goes to show that you can't believe everything you read, even at cisco.com.

Anyway, as you can see above the first address is the current working MAC address of the interface which can be manually changed with the mac-address command, but is normally the same as the permanent BIA shown in parentheses.