SMC Networks SMC8612XL3 F 1.0.1.3 manual 227, Configuring Vrrp Groups, Address Assignment

CONFIGURING ROUTER REDUNDANCY

Configuring VRRP Groups

To configure VRRP, select an interface on one router in the group to serve as the master virtual router. This physical interface is used as the virtual address for the router group. Now set the same virtual address and a priority on the backup routers, and configure an authentication string. You can also enable the preempt feature which allows a router to take over as the master router when it comes on line.

Command Usage

Address Assignment –

•The IP address assigned to the virtual router must already be configured on the router that will be the Owner. In other words, the IP address for the virtual router exists on one, and only one, router in the virtual router group, and the network mask for the virtual router address is derived from the Owner. The Owner will also assume the role of the Master virtual router in the group.

•If you have multiple secondary addresses configured on the current VLAN interface, you can add any of these addresses to the virtual router group.

•The interfaces of all routers participating in a virtual router group must be within the same IP subnet.

•VRRP creates a virtual MAC address for the master router based on a standard prefix, with the last octet equal to the group ID. When a backup router takes over as the master, it continues to forward traffic addressed to this virtual MAC address. However, the backup router cannot reply to ICMP pings sent to addresses associated with the virtual group because the IP address owner is off line.

Virtual Router Priority –

•The Owner of the virtual IP address is automatically assigned the highest possible virtual router priority of 255. The backup router with the highest priority will become the master router if the current master

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