R0106-HP MSR Router Series High Availability Command Reference(V7)

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In preemptive mode, a backup takes over as the master and sends VRRP advertisements when it detects
that it has a higher priority than the master. The previous master then becomes a backup. This mechanism
makes sure the master is always the device with the highest priority.
To avoid frequent state changes among members in a VRRP group and to provide the backups enough
time to collect information (such as routing information), a backup does not immediately become the
master after it receives an advertisement with lower priority than the local priority. Instead, it waits for a
period of time before taking over as the master.
Examples
# Enable the preemptive mode for GigabitEthernet 2/0/1, and set the preemption delay to 5 seconds.
<Sysname> system-view
[Sysname] interface gigabitethernet 2/0/1
[Sysname-GigabitEthernet2/0/1] vrrp vrid 1 preempt-mode delay 5
Related commands
display vrrp
vrrp vrid priority
Use vrrp vrid priority to configure the priority of the device in an IPv4 VRRP group.
Use undo vrrp vrid priority to restore the default.
Syntax
vrrp vrid virtual-router-id priority priority-value
undo vrrp vrid virtual-router-id priority
Default
The priority of a device in an IPv4 VRRP group is 100.
Views
Interface view
Predefined user roles
network-admin
Parameters
virtual-router-id: Specifies an IPv4 VRRP group by its virtual router ID in the range of 1 to 255.
priority-value: Specifies a priority value in the range of 1 to 254. A higher number indicates a higher
priority.
Usage guidelines
VRRP determines the role (master or backup) of each device in a VRRP group by priority. A device with
a higher priority is more likely to become the master.
VRRP priority is in the range of 0 to 255, and a greater number represents a higher priority. Priorities 1
to 254 are configurable. Priority 0 is reserved for special uses, and priority 255 is for the IP address
owner. The device acting as the IP address owner in a VRRP group always has a running priority of 255
and acts as the master as long as it works correctly.
Examples
# Configure the priority of the router in VRRP group 1 on GigabitEthernet 2/0/1 to 150.