Hi there, i had to modify MAC Adress on a VRF SVI in order to bridge my vlan to another one in the global router (bridge with FWSM). It resolved the issue i had (thanks to people here). On another setup, i also had to modify mac adress in two pair of Cisco ASA 5550 running each multiple context in failover.
On th VRF mapped svi, i only modify a digit of the mac adress (replacing the first 0 with a 1....) In the ASA, we made an internal definition mac Structure (relative to context id, context vlan etc etc).
My question is : Is there a range of usable MAC adress we can use for this kind of purpose ? Or a convention for modifying it relative to the kind of equipment ?
Have a look at :-
Be careful about the least significant bit of the most significant byte though. If it is set to 1 the MAC address will be treated as a Multicast. Make sure it is zero so that the MAC address will be treated as a Unicast.
The link suggests that the second least significant bit should be set to 1 for a Locally Administered Address as it is always zero for a Universally Administered Address.
The link explains it all.