Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 598)

The virtual router shown in the figure above is identified as Group 1. A physical router forwards
packets for the virtual router. This physical router is called the master router.
The following are some common VRRP-related terms and concepts:
• Virtual router — A collection of physical routers that can use either the VRRP or VRRP Extended
(VRRP-E) protocol to provide redundancy to routers within a LAN.
NOTE
Most of the information presented here applies to both VRRP and VRRP-E, and, therefore, the term
"VRRP" is often used to mean either VRRP or VRRP-E. Where there are differences between the two
protocols, these differences are explicitly described.
• Virtual router group — A group of physical routers that are assigned to the same virtual router.
• Virtual router address — The address you are backing up:
‐ For VRRP: The virtual router IP address must belong to the same subnet as a real IP
address configured on the VRRP interface, and can be the same as a real IP addresses
configured on the VRRP interface. The virtual router whose virtual IP address is the same
as a real IP address is the IP address owner and the default master.
‐ For VRRP-E: The virtual router IP address must belong to the same subnet as a real IP
address configured on the VRRP-E interface, but cannot be the same as a real IP address
configured on the VRRP-E interface.
• Owner — This term applies only to the VRRP protocol, not to VRRP-E. The owner is the physical
router whose real interface IP address is the IP address that you assign to the virtual router. The
owner responds to packets addressed to any of the IP addresses in the corresponding virtual
router. The owner, by default, is the master and has the highest priority (255).
• Master — The physical router that responds to packets addressed to any of the IP addresses in the
corresponding virtual router. For VRRP, if the physical router whose real interface IP address is the
IP address of the virtual router, then this physical router is always the master. For VRRP-E, the
router with the highest priority becomes the master. The priority command is used to set priority for
a physical router.
• Backup — Routers that belong to a virtual router but are not the master. Then, if the master
becomes unavailable, the backup router with the highest priority (a configurable value) becomes the
new master. By default, routers are given a priority of 100.
NOTE
VRRP operation is independent of the Open Shortest Path First (OSPF) protocol or the Border
Gateway Protocol (BGP).and is unaffected when enabled on interfaces running those protocols.
VRRP multigroup clusters
The figure below depicts a commonly employed virtual router topology. This topology introduces
redundancy by configuring two virtual router groups — the first group has Router 1 as the master and
Router 2 as the backup, and the second group has Router 2 as the master and Router 1 as the
backup. This type of configuration is sometimes called Multigroup VRRP.
VRRP multigroup clusters
598 Network OS Administrator’s Guide
53-1003225-04