H3C S3600 Series Command Manual

1-9
vrrp vrid preempt-mode
Syntax
vrrp vrid virtual-router-id preempt-mode [ timer delay delay-value ]
undo vrrp vrid virtual-router-id preempt-mode
View
VLAN interface view
Parameters
virtual-router-id: VRRP group ID, ranging from 1 to 255.
delay-value: Preemption delay period (in seconds), ranging from 0 to 255.
Description
Use the vrrp vrid preempt-mode command to configure a switch to operate in the preemptive mode
and set the preemption delay period.
Use the undo vrrp vrid preempt-mode command to cancel the configuration, that is, configure the
switch to work in the non-preemptive mode.
By default, switches in a VRRP group operate in the preemptive mode, with the preemption delay
period set to 0 seconds.
If you want a switch with high priority to preempt the master, configure the switch to operate in the
preemptive mode. You can also set the delay period for preemption as needed.
For S3600 series, you can enable the preemptive mode for switches in a VRRP group:
z In a VRRP group where the preemptive mode is not enabled, once a switch in the VRRP group
becomes the master, other switches, even if they are with a higher priority later, do not preempt the
master as long as the master is not down.
z In a VRRP group where switches are enabled with the preemptive mode, a backup sends out
VRRP advertisements to trigger a new master election if it finds its priority is higher than that of the
current master, and finally becomes the new master. The former master becomes a backup
accordingly.
You can also set the preemptive delay for the switches in a VRRP group. Setting a preemption delay
period aims at:
z In an unstable network, backups in a VRRP group possibly cannot receive VRRP advertisements
from the master in time due to network congestions. This causes the master of the VRRP group to
be determined frequently. In this case, the backup considers itself as the master and sends out
VRRP advertisements to elect the master. This causes the master of the VRRP group to be
determined frequently.
z With the configuration of preemption delay, if a backup does not receive VRRP advertisements
from the master in time, it waits for a while before switching to a new master. The backup does not
send VRRP advertisements if it receives VRRP advertisements from the master during the
specified delay period.
Examples
# Configure the switch to operate in the preemptive mode.
<Sysname> system-view

H3C S3600 Series Specifications

General

Brand	H3C
Model	S3600 Series
Category	Switch
Language	English