The value of tmnxBsxAarpInstPriority specifies the priority of this
AARP instance advertised to the AARP peer. It is compared to
the peer's priority, and the AARP instance with the
higher priority enters the master state and the one with the lower
priority enters the backup state. If the priorities are
identical, the instance peer IP addresses are used as a tie-breaker
with the peer with the higher address entering the master state and
the other the backup.