This chapter describes how to configure Virtual Routing Redundancy
Protocol (VRRP) on the switch. VRRP can help create redundancy on
networks in which end-stations are statically configured with the default
gateway IP address.
The topics covered in this chapter include:
Default VRRP Values
Configuring VRRP Features (Web)
Configuring VRRP Features (CLI)
VRRP Configuration Example
The Virtual Router Redundancy (VRRP) protocol is designed to handle
default router (L3 switch) failures by providing a scheme to dynamically elect
a backup router. VRRP can help minimize black hole periods due to the
failure of the default gateway router during which all traffic directed towards
it is lost until the failure is detected.
How Does VRRP Work?
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 switch may be
configured as a virtual router. Either a physical port or a routed VLAN may