Owner router: The Owner router is automatically configured with the highest VRRP router priority in the VR (255). It operates as the Master router for the VR unless it becomes unavailable to the network. All Virtual Router members can be configured so virtual IP is not the same as physical (or real) IP. Such virtual address can be called pure virtual IP address.

Master router: The Owner or Backup router that is the physical forwarding agent for routed traffic using the VR as a gateway. There can be only one router operating as the Master for a network. If the router configured as the Owner for a VR is available to the network, it will also be the Master. If the Owner fails or loses availability to the network, the highest-priority Backup becomes the Master.

Backup: A router configured in a VR as a Backup to the Owner/Master for the same VR. There must be a minimum of one Backup in a VR to support VRRP operation if the Owner/Master fails. Every backup is created with a configurable priority (default: 100). This priority determines the precedence for becoming the Master of the VR if the Owner or another Backup operating as Master becomes unavailable.

When the current Master router is no longer available, the Backup router with highest priority will become current master. When a router with higher priority becomes available, it is switched to master. The user can override this behavior by disabling preemption mode.

Virtual Router (VR): Consists of one Owner/Master router and one or more Backup routers that belong to the same network. The Owner is the router that owns any IP addresses associated with the VR. The VR has one virtual IP address (multiple virtual IP addresses for multinetted interfaces) that correspond to a real IP address on the Owner. A VR includes the following:
  • A VR identification (VRID) configured on all VRRP routers in the same network. For a multinetted interface, the VRID is configured on all routers in the same subnet.

  • The same VIP configured on each instance of the same VR.

  • The status of either Owner or Backup configured on each instance of the same VR. There can be one Owner and one or more Backups configured on each VR.

  • The priority level configured on each instance of the VR. On the Owner router, the highest priority setting of 255 is automatically fixed. On Backups, the default priority setting is 100 and configurable.

  • A VR MAC address that is not configurable.

Virtual IP address (VIP): The VIP associated with a VR must be a real IP address already configured in the associated interface on the Owner router.
  • If the VIP is an IPv6 address, a link-local address must be configured before adding a global IPv6 address.

  • The Owner and all Backup routers belonging to the VR have this IP address configured in their VRID contexts as the VIP.

  • A subnetted interface allows multiple VIPs. If there are fewer IP addresses in an interface and a user wants VRRP support on multiple subnets, configure a separate VR instance for each IP address in the interface.

VRID: The identifier for a VR configured on an interface. A VRID can be used for only one VR in any interface on a router. It can be used again for a different VR in a different interface.