80
The output shows the BFD detection result: if the next hop 10.2.1.2 is unreachable (the status of the track
entry is Negative), the backup static route takes effect, and Router A forwards packets to 30.1.1.0/24
through Router C and Router B.
# When the master route fails, the hosts in 20.1.1.0/24 can still communicate with the hosts in
3 0 .1.1. 0 / 2 4 .
[RouterA] ping -a 20.1.1.1 30.1.1.1
Ping 30.1.1.1: 56 data bytes, press CTRL_C to break
Reply from 30.1.1.1: bytes=56 Sequence=1 ttl=254 time=2 ms
Reply from 30.1.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms
Reply from 30.1.1.1: bytes=56 Sequence=3 ttl=254 time=1 ms
Reply from 30.1.1.1: bytes=56 Sequence=4 ttl=254 time=2 ms
Reply from 30.1.1.1: bytes=56 Sequence=5 ttl=254 time=1 ms
--- Ping statistics for 30.1.1.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.00% packet loss
round-trip min/avg/max/std-dev = 1/1/2/1 ms
# The output on Router B is similar to that on Router A. When the master route fails, the hosts in
30.1.1.0/24 can still communicate with the hosts in 20.1.1.0/24.
[RouterB] ping -a 30.1.1.1 20.1.1.1
Ping 20.1.1.1: 56 data bytes, press CTRL_C to break
Reply from 20.1.1.1: bytes=56 Sequence=1 ttl=254 time=2 ms
Reply from 20.1.1.1: bytes=56 Sequence=2 ttl=254 time=1 ms
Reply from 20.1.1.1: bytes=56 Sequence=3 ttl=254 time=1 ms
Reply from 20.1.1.1: bytes=56 Sequence=4 ttl=254 time=1 ms
Reply from 20.1.1.1: bytes=56 Sequence=5 ttl=254 time=1 ms
--- Ping statistics for 20.1.1.1 ---
5 packet(s) transmitted, 5 packet(s) received, 0.00% packet loss
round-trip min/avg/max/std-dev = 1/1/2/1 ms
VRRP-Track-interface management collaboration configuration
example
In this example, the master monitors the uplink interface.
Network requirements
• As shown in Figure 21, Host A needs to access Host B on the Internet. The default gateway of Host
A i s 10 .1.1.10 / 2 4 .
• Router A and Router B belong to VRRP group 1, whose virtual IP address is 10.1.1.10.
• When Router A works correctly, packets from Host A to Host B are forwarded through Router A.
When VRRP detects that a fault is on the uplink interface of Router A through the interface
management module, packets from Host A to Host B are forwarded through Router B.