Vrrp Vrid Preempt-Mode - H3C S7500E Series Command Manual

Command Manual – HA
H3C S7500E Series Ethernet Switches
By default, TTL check on VRRP packets is enabled.
Examples
# Disable TTL check on VRRP packets.
<Sysname> system-view
[Sysname] interface vlan-interface 2
[Sysname-Vlan-interface2] vrrp un-check ttl

1.1.8 vrrp vrid preempt-mode

Syntax
vrrp vrid virtual-router-id preempt-mode [ timer delay delay-value ]
undo vrrp vrid virtual-router-id preempt-mode [ timer delay ]
View
Interface view
Parameters
virtual-router-id: Virtual router ID or VRRP standby group number, in the range 1 to 255.
timer delay delay-value: Sets preemption delay. The delay-value argument is in the
range of 0 to 255 seconds and defaults to 0 seconds.
Description
Use the vrrp vrid preempt-mode command to enable preemption on the switch and
configure its preemption delay in the specified standby group.
Use the undo vrrp vrid preempt-mode command to disable preemption on the switch
in the specified standby group.
Use the undo vrrp vrid preempt-mode timer delay command to restore the default
preemption delay, that is, zero seconds.
The default mode is immediate preemption without delay.
On an instable network, the standby group member in the backup state may not
normally receive the packets from the master due to network congestion, resulting in
frequent master/backup state transition of the standby group members. Preemption
delay is introduced to solve this problem. With a preemption delay set, if the backup
does not receive the packet from the master duly, it waits for a period to see whether it
can receive any packet from the master. If the specified period elapses but it still
receives no packet from the master, it becomes the master.
Note that before executing the command, you need to create a standby group on an
interface and configure the virtual IP address of the standby group.
Chapter 1 VRRP Configuration Commands
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