Vrid; Priority - Alcatel-Lucent 7705 Configuration Manual

VRRP Components

VRID

The VRID must be configured with the same value on each virtual router associated with the
virtual IP address or IP addresses. The VRID is placed in all VRRP advertisement messages
sent by each virtual router.

Priority

The priority value affects the interaction between all virtual routers with the same VRID
participating on the same LAN. The priority value is used during the election process to
determine which backup router (or non-owner) will assume the role of Master. The priority
value can only be configured if the defined IP address on the IP interface is different from the
virtual router IP address meaning that the virtual router is a non-owner.
If the IP address on the IP interface matches the virtual router IP address (owner mode), the
priority value is fixed at 255, the highest value possible. This virtual router member is
considered the owner of the virtual router IP address. There can only be one owner of the
virtual router IP address for all virtual router members.
The priority value 0 is reserved for VRRP advertisement message purposes. It is used to tell
other virtual routers with the same VRID that this virtual router is no longer acting as master,
triggering a new election process. If this happens, each virtual router backup sets its master
down timer equal to the skew time value. This shortens the time before one of the virtual
router backups becomes master.
The current virtual router master must transmit a VRRP advertisement message immediately
upon receipt of a VRRP message with priority set to 0. This prevents another virtual router
backup from becoming master for a short period of time.
Non-owner virtual routers can be configured with a priority of 254 through 1. The default
value is 100. Multiple non-owners can share the same priority value. If during an election, a
tie is encountered, then the router with the highest IP address will win the election. In other
words, the IP addresses of the non-owners that make the tie, are used to break the tie.
The priority is also used to determine when to preempt the existing master. If the preempt
mode value is true, VRRP advertisement messages from inferior (lower-priority) masters are
discarded, causing the master down timer to expire and the higher-priority backup router to
transition to the master state.
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• VRRP Advertisement Message IP Address List Verification
• Policies
7705 SAR OS Router Configuration Guide