Lenovo ThinkSystem NE2552E Application Manual page 552

VRID
VRRP
552
NE2552E Application Guide for ENOS 8.4
Virtual Router Identifier. In VRRP, a numeric ID is used by each virtual router
to create its MAC address and identify its peer for which it is sharing this
VRRP address. The VRRP MAC address as defined in the RFC is
00‐00‐5E‐00‐01‐<VRID>.
If you have a VRRP address that two switches are sharing, then the VRID
number needs to be identical on both switches so each virtual router on each
switch knows with whom to share.
Virtual Router Redundancy Protocol. A protocol that acts very similarly to
Ciscoʹs proprietary HSRP address sharing protocol. The reason for both of
these protocols is so devices have a next hop or default gateway that is always
available. Two or more devices sharing an IP interface are either advertising or
listening for advertisements. These advertisements are sent via a broadcast
message to an address such as 224.0.0.18.
With VRRP, one switch is considered the master and the other the backup. The
master is always advertising via the broadcasts. The backup switch is always
listening for the broadcasts. Should the master stop advertising, the backup
will take over ownership of the VRRP IP and MAC addresses as defined by
the specification. The switch announces this change in ownership to the
devices around it by way of a Gratuitous ARP, and advertisements. If the
backup switch didnʹt do the Gratuitous ARP the Layer 2 devices attached to
the switch would not know that the MAC address had moved in the network.
For a more detailed description, refer to RFC 2338.