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4.8.6 (Optional) Configuring Smooth VRRP IPv6 Switching
After smooth VRRP IPv6 switching is enabled, the backup Routers learn about the smooth
switching time, and retain their status within the smooth switching time, preventing service
traffic loss resulted from a master/backup VRRP switchover.
Context
If the master Router in a VRRP IPv6 backup group performs an AMB/SMB switchover, the
master and backup Routers may fail to communicate with each other during the switchover.
During this period of time, the backup Router with the highest priority becomes the new master
device if backup Routers receive no VRRP Advertisement packet after the interval at which
VRRP IPv6 Advertisement packets are sent expires. In this situation, two master Routers coexist.
After the original master Router completes the AMB/SMB switchover, it detects that it has a
higher priority than the other master Router, and therefore retains the Master state. The other
master Router switches back to the Backup state. During this process, the links between the
VRRP IPv6 backup group and user device are switched twice, causing unstable service
transmission.
After the Router is enabled with smooth switching, the master Router sends VRRP IPv6
Advertisement packets at the originally configured interval. The packets carry the smooth
switching time. After receiving the packets, backup Routers learn the smooth switching time
and prolongs the timeout period for receiving VRRP Advertisement packets based on the learned
time, ensuring the stability of the VRRP backup group status.
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run:
vrrp timer-advertise learning enable
The function to learn the interval at which VRRP IPv6 Advertisement packets are sent is enabled.
By default, the Router is enabled to learn the interval at which VRRP IPv6 Advertisement packets
are sent.
Step 3
Run:
vrrp smooth-switching timer
timer-value
Smooth VRRP IPv6 switching is enabled, and the interval carried in VRRP IPv6 Advertisement
packets during smooth switching is configured.
By default, smooth VRRP switching is enabled, and the interval carried in VRRP IPv6
Advertisement packets is 100 seconds.
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
4 VRRP Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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