Single VRRP group configuration example

As shown in Figure 23, Router A and Router B form a VRRP group. They use the virtual IP address 10.1.1.111/24 to provide gateway service for the subnet where Host A resides.

Router A operates as the master to forward packets from Host A to Host B. When Router A fails, Router B takes over to forward packets for Host A.

Configure Router A to operate in preempt mode so Router A can forward traffic as long as Router A operates correctly. Set the preemption delay to 5000 centiseconds to avoid frequent status change.

1. Configure Router A:

   # Specify an IP address for Router A.

   <RouterA> system-view
   [RouterA] interface gigabitethernet 1/0/1
   [RouterA-GigabitEthernet1/0/1] ip address 10.1.1.1 255.255.255.0
   

   # Create VRRP group 1 on GigabitEthernet 1/0/1 and set its virtual IP address to 10.1.1.111.

   [RouterA-GigabitEthernet1/0/1] vrrp vrid 1 virtual-ip 10.1.1.111
   

   # Assign Router A a higher priority than Router B in VRRP group 1, so Router A can become the master.

   [RouterA-GigabitEthernet1/0/1] vrrp vrid 1 priority 110
   

   # Configure Router A to operate in preemptive mode, so it can become the master whenever it operates correctly. Set the preemption delay to 5000 centiseconds to avoid frequent status switchover.

   [RouterA-GigabitEthernet1/0/1] vrrp vrid 1 preempt-mode delay 5000
   

2. Configure Router B:

   # Specify an IP address for Router A.

   <RouterB> system-view
   [RouterB] interface gigabitethernet 1/0/1
   [RouterB-GigabitEthernet1/0/1] ip address 10.1.1.2 255.255.255.0
   

   # Create VRRP group 1 on GigabitEthernet 1/0/1 and set its virtual IP address to 10.1.1.111.

   [RouterB-GigabitEthernet1/0/1] vrrp vrid 1 virtual-ip 10.1.1.111
   

   # Set the priority of Router B to 100 in VRRP group 1.

   [RouterB-GigabitEthernet1/0/1] vrrp vrid 1 priority 100
   

   # Configure Router B to operate in preemptive mode, and set the preemption delay to 5000 centiseconds.

   [RouterB-GigabitEthernet1/0/1] vrrp vrid 1 preempt-mode delay 5000
   

# Ping Host B from Host A. (Details not shown.)

# Display detailed information about VRRP group 1 on Router A.

[RouterA-GigabitEthernet1/0/1] display vrrp verbose
IPv4 Virtual Router Information:
 Running Mode      : Standard
 Total number of virtual routers : 1
   Interface GigabitEthernet1/0/1
     VRID           : 1                    Adver Timer  : 100
     Admin Status   : Up                   State        : Master
     Config Pri     : 110                  Running Pri  : 110
     Preempt Mode   : Yes                  Delay Time   : 5000
     Auth Type      : None
     Virtual IP     : 10.1.1.111
     Virtual MAC    : 0000-5e00-0101
     Master IP      : 10.1.1.1

# Display detailed information about VRRP group 1 on Router B.

[RouterB-GigabitEthernet1/0/1] display vrrp verbose
IPv4 Virtual Router Information:
 Running Mode      : Standard
 Total number of virtual routers : 1
   Interface GigabitEthernet1/0/1
     VRID           : 1                    Adver Timer  : 100
     Admin Status   : Up                   State        : Backup
     Config Pri     : 100                  Running Pri  : 100
     Preempt Mode   : Yes                  Delay Time   : 5000
     Become Master  : 412ms left
     Auth Type      : None
     Virtual IP     : 10.1.1.111
     Master IP      : 10.1.1.1

The output shows that Router A is operating as the master in VRRP group 1 to forward packets from Host A to Host B.

# Disconnect the link between Host A and Router A, and verify that Host A can still ping Host B. (Details not shown.)

# Display detailed information about VRRP group 1 on Router B.

[RouterB-GigabitEthernet1/0/1] display vrrp verbose
IPv4 Virtual Router Information:
 Running Mode      : Standard
 Total number of virtual routers : 1
   Interface GigabitEthernet1/0/1
     VRID           : 1                    Adver Timer  : 100
     Admin Status   : Up                   State        : Master
     Config Pri     : 100                  Running Pri  : 100
     Preempt Mode   : Yes                  Delay Time   : 5000
     Auth Type      : None
     Virtual IP     : 10.1.1.111
     Virtual MAC    : 0000-5e00-0101
     Master IP      : 10.1.1.2

The output shows that when Router A fails, Router B takes over to forward packets from Host A to Host B.

# Recover the link between Host A and Router A, and display detailed information about VRRP group 1 on Router A.

[RouterA-GigabitEthernet1/0/1] display vrrp verbose
IPv4 Virtual Router Information:
 Running Mode      : Standard
 Total number of virtual routers : 1
   Interface GigabitEthernet1/0/1
     VRID           : 1                    Adver Timer  : 100
     Admin Status   : Up                   State        : Master
     Config Pri     : 110                  Running Pri  : 110
     Preempt Mode   : Yes                  Delay Time   : 5000
     Auth Type      : None
     Virtual IP     : 10.1.1.111
     Virtual MAC    : 0000-5e00-0101
     Master IP      : 10.1.1.1

The output shows that after Router A resumes normal operation, it becomes the master to forward packets from Host A to Host B.