How assign new mac address of SVI Interface

[ambivert skill]

Hi ,

How can we assign a new MAC address of SVI Interface and from what range we have to choose from when we have the following output

Router(config-if)#mac-address ?

  H.H.H  MAC address

Thank you

Ambivert Skill

[cadet alain · Accepted solution]

Hi,

you can choose whatever MAC you want as long as:

-you don't put all zeroes

-it is not the same as another interface on this device or another

-it is not a group address, that is, the I/G bit must be zero

-it is better for administration and troubleshooting to flip the U/L bit to 1( meaning it is not a burned-in address)

here are the interesting bits:

xxxx.xxxx.xxxx  each x is a hexadecimal character so it is 4 bits: bbbb

so the first octet( beginning from left) is bbbbbbbb  this is the U/L bit, bbbbbbbb  this is the I/G bit.

let's take some example:

-0011.1111.1111  0011= 00000000  so U/L=0 and I/G=0  so valid

-0100.1111.1111 0100= 00000001 so U/L=0 and I/G=1( multicast address), so it is not valid

-0200.1111.1111 0200= 00000010 so U/L=1(spoffed address) and I/G=0(unicast) so valid

Regards

Alain

Don't forget to rate helpful posts.

[ambivert skill]

Thanks Cadet for clearing the concept.

Regards

Ambivert Skill