Virtual Router Redundancy Protocol - NETGEAR ProSafe GSM7328 Administration Manual

Chapter 6

Virtual Router Redundancy Protocol

When an end station is statically configured with the address of the router that will handle its
routed traffic, a single point of failure is introduced into the network. If the router goes down, the
end station is unable to communicate. Since static configuration is a convenient way to assign
router addresses, Virtual Router Redundancy Protocol (VRRP) was developed to provide a backup
mechanism.
VRRP eliminates the single point of failure associated with static default routes by enabling a
backup router to take over from a "master" router without affecting the end stations using the
route. The end stations will use a "virtual" IP address that will be recognized by the backup router
if the master router fails. Participating routers use an election protocol to determine which router is
the master router at any given time. A given port may appear as more than one virtual router to the
network, also, more than one port on a 7000 Series Managed Switch may be configured as a virtual
router. Either a physical port or a routed VLAN may participate.
6-1
v1.1, May 2006