R21xx-HP FlexFabric 11900 High Availability Configuration Guide

Configuring BFD for a VRRP backup to monitor the master

Network requirements

• As shown in Figure 22, Switch A and Switch B belong to VRRP group 1, whose virtual IP address is

192.168.0.10.

• The default gateway of the hosts in the LAN is 192.168.0.10. When Switch A works properly, the

hosts in the LAN access the external network through Switch A. When Switch A fails, the hosts in the

LAN access the external network through Switch B.

• If the master in a VRRP group fails and BFD is not configured, the backup cannot become the master

until the configured timeout timer expires. The timeout is usually 3 to 4 seconds, a long delay for

most applications. To solve this problem, VRRP uses BFD to probe the state of the master. Once the

master fails, the backup can become the new master in milliseconds.

Figure 22 Network diagram

Configuration procedure

1. Create VLANs and assign corresponding ports to them. Configure the IP address of each VLAN

interface as shown in Figure 22. (Details not shown.)

2. Configure VRRP on Switch A:

<SwitchA> system-view

[SwitchA] interface vlan-interface 2

# Create VRRP group 1, and configure the virtual IP address 192.168.0.10 for the group. Set the

priority of Switch A in VRRP group 1 to 110.

[SwitchA-Vlan-interface2] vrrp vrid 1 virtual-ip 192.168.0.10

[SwitchA-Vlan-interface2] vrrp vrid 1 priority 110

[SwitchA-Vlan-interface2] return

Internet

Virtual router

Virtual IP address:

192.168.0.10

Vlan-int2

192.168.0.101/24

Vlan-int2

192.168.0.102/24

Switch A

Master

Switch B

Backup

L2 switch

VRRP packets

BFD probe packets