Huawei NetEngine80E Configuration Manual - Reliability page 158

HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
Context
If a link between devices in a VRRP IPv4 backup group fails, VRRP IPv4 Advertisement packets
cannot be sent to negotiate states. Backup devices will attempt to preempt the Master state after
a period three times the interval at which VRRP IPv4 Advertisement packets are broadcast.
During this period of time, service data is lost. To prevent this problem, the VRRP IPv4 backup
group can be associated with BFD sessions. The BFD sessions are established between the master
and backup devices to rapidly detect faults. If a fault occurs, the BFD module rapidly notifies
the VRRP IPv4 backup group of the fault and triggers a master/backup VRRP switchover. VRRP
IPv4 association involves the following functions:
l
l
A VRRP IPv4 backup group can track a maximum of eight BFD sessions and a maximum of
eight interfaces.
Perform the following steps on the device that needs to implement a rapid master/backup VRRP
switchover:
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
interface interface-type interface-number [.subinterface-number ]
The view of the interface where the VRRP IPv4 backup group is configured is displayed.
Step 3 Run either of the following commands:
l
Issue 02 (2014-09-30)
Association with a common BFD session: The association allows a master/backup VRRP
switchover to be performed after VRRP priorities change.
Association with a link or peer BFD session: The association allows a master/backup VRRP
switchover to be performed within milliseconds after the link or peer BFD session detects
a fault.
NOTE
When configuring a VRRP IPv4 backup group to track a BFD session, use either of the following parameters
as needed:
l session-name bfd-configure-name: allows only a static BFD session with automatically negotiated
discriminators to be bound to the VRRP IPv4 backup group.
l session-id: allows only a static BFD session to be bound to the VRRP IPv4 backup group.
vrrp vrid virtual-router-id track bfd-session { bfd-session-id | session-name
bfd-configure-name } [ increased value-increased | reduced value-reduced ]
The VRRP IPv4 backup group is configured to track a common BFD session. During the
configuration, use either of the following parameters as needed:
increased value-increased: specifies the value by which the VRRP priority increases if the
tracked BFD session becomes Failed. The value ranges from 1 to 255. Only the IP address
owner has priority value 255, and the largest priority value can be set to 254. This parameter
takes effect only on backup devices.
reduced value-reduced: specifies the value by which the VRRP priority reduces if the tracked
BFD session becomes Failed. The value ranges from 1 to 255. The smallest priority value
can be set to 1. Priority value 0 is reserved for special use. If a backup device receives a
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
4 VRRP Configuration
141