Because the RFC says so: http://tools.ietf.org/html/rfc3768#section-7.3
:-) Actually I'd say it's because it's not *really* a multicast MAC address. It's closer to an Anycast address in concept. Intentional collision in order to provide a redundant service. And Anycast addresses (to continue the metaphor) are actually unicast addresses, not multicast ones. Among other things, Cisco switches get rather upset at the idea of binding a unicast IP address to a multicast MAC address (in that, they won't do it -- it's one reason Microsoft NLB is such a pain). Perhaps the protocol designers decided to make sure such conflicts weren't a problem. On Sat, Oct 20, 2012 at 4:13 PM, Mark Beynon <[email protected]> wrote: > Hopefully a simple question, but I can't find the answer and i'm hoping the > wider collective can... > > Multicast IP addresses derive multicast MAC addresses, which start 0100.5e. > > So why is the vrrp MAC 0000.5e00.01xx?? (not 0100.5e etc) > > ? > > Thanks > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com > > http://onlinestudylist.com/mailman/listinfo/ccie_rs > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com http://onlinestudylist.com/mailman/listinfo/ccie_rs
