VRRP: Increasing Reliability and Failover with the Virtual Router Redundance Protocol

2.8. Virtual Routers with Multiple IP Addresses

VRRP Internet Draft hints at the possibility of protecting multiple IP addresses with a single virtual router by using the expression IP address(es) without explicitly going into the details of this characteristic. As a matter of fact, a physical interface may have multiple IP addresses that can be on the same (usually rare) or different subnets, the latter being referred to as multinetting. Network administrators commonly use multinetting when they need to renumber a network, that is, assign new addresses with a different subnet definition. In such cases, to ease the transition both subnets are maintained for a brief period.

When a VRRP router has more than one address associated with its interface, ...