Nokia Network Voyager, Reference Manual

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8
Configuring Router Services
460 Voyager Reference Guide
Priority
Priority provides a way to prefer one router in favor of another during
contention for a failed router's addresses. If more than one backup router is
configured for a Virtual Router, only one of them will assume forwarding
responsibility for the failed default router. The routers' relative priorities are
used by VRRP to determine which router that will be.
! Priority is a numeric value; the higher the value, the higher the priority. If
the configured priorities of two backup routers is equal, and the backup
routers become masters at the same time, their IP addresses are used as a
tiebreaker.
! The router that owns the IP addresses configured in the Virtual Router
always has the highest priority. Once a failed router recovers, it will
always reclaim responsibility for forwarding traffic sent to its own
addresses. But the failed router would assume responsibility for traffic
sent to virtual addresses that are not its real interface addresses only if its
priority is higher than the priority of the current master.
You specify priority when configuring a router to back up another.
Note
The range of priority values you can specify is 1-254. When you specify
priority values for backup routers, it is better to specify high priority
values, for example 254, 253, etc. The higher values can decrease the
time it takes for a backup router to take over for a failed router by up to
one second.
Hello Interval
The Hello Interval is the time interval (in seconds) between VRRP
Advertisements. It also determines the fail-over interval; that is, how long it
takes a backup router to take over from a failed default router.
VRRP Advertisements are broadcast on the LAN by the current master of
each Virtual Router. Backup routers listen for these Advertisements and