3com S7906E Instruccion De Instalación

 

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The above output indicates that when BFD detects that Switch A fails, it notifies VRRP through the track 

module to change the status of Switch B to master, without waiting for a period three times the 

advertisement interval, so that a backup can quickly preempt as the master. 

z 

As shown in 

, Switch A and Switch B belong to VRRP group 1, whose virtual IP address 

is 192.168.0.10. 

z 

The default gateway of the hosts in the LAN is 192.168.0.10. 

z 

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

When Switch A detects that the uplink is down through BFD, it decreases its priority so that Switch 

B can preempt as the master, thus ensuring that the hosts in the LAN can access the external 

network through Switch B. 

Figure 1-4 Network diagram for monitoring uplinks using BFD 

Internet

Master

uplink device

Backup

uplink device

Uplink

Virtual IP address:

192.168.0.10

Vlan-int2

192.168.0.101/24

Vlan-int2
192.168.0.102/24

Switch A

Switch B

Vlan-int3

1.1.1.1/24

Vlan-int3

1.1.1.2/24

L2 switch

Uplink

VRRP packets

BFD probe packets

 

 

1)  Configure BFD on Switch A. 

# Configure the source address of BFD echo packets as 10.10.10.10. 

<SwitchA> system-view 

[SwitchA] bfd echo-source-ip 10.10.10.10 

2)  Create a track entry to be associated with the BFD session on Switch A. 

# Create track entry 1 to be associated with the BFD session to check whether the uplink device with the 

IP address 1.1.1.2 is reachable. 

[SwitchA] track 1 bfd echo interface vlan-interface 3 remote ip 1.1.1.2 local ip 1.1.1.1 

3)  Configure VRRP on Switch A