Example for Configuring a VRRP Group in Redundancy Mode

Networking Requirements

In Figure 1, HostA is dual-homed to SwitchA and SwitchB through the switch. To ensure nonstop service transmission, a VRRP group in redundancy mode needs to be configured on SwitchA and SwitchB.

The host uses SwitchA as the default gateway to connect to the Internet. When SwitchA becomes faulty, SwitchB functions as the gateway. This implements gateway backup.
After SwitchA recovers, it becomes the master again to transmit data after a preemption delay of 20s.

In this scenario, to avoid loops, ensure that all connected interfaces have STP disabled and connected interfaces are removed from VLAN 1. If STP is enabled and VLANIF interfaces of switches are used to construct a Layer 3 ring network, an interface on the network will be blocked. As a result, Layer 3 services on the network cannot run normally.

Figure 1 Networking diagram for configuring a VRRP group

Device	Interface	VLANIF Interface	IP Address
SwitchA	GE0/0/1	VLANIF 300	192.168.1.1/24
SwitchA	GE0/0/2	VLANIF 100	10.1.1.1/24
SwitchB	GE0/0/1	VLANIF 200	192.168.2.1/24
SwitchB	GE0/0/2	VLANIF 100	10.1.1.2/24
SwitchC	GE0/0/1	VLANIF 300	192.168.1.2/24
	GE0/0/2	VLANIF 200	192.168.2.2/24
	GE0/0/3	VLANIF 400	172.16.1.1/24

Configuration Roadmap

The configuration roadmap is as follows:

Assign an IP address to each interface and configure a routing protocol to ensure network connectivity.
Configure a VRRP group on SwitchA and SwitchB and set a higher priority for SwitchA so that SwitchA functions as the master to forward traffic. Then, set the preemption delay to 20s on SwitchA, and set a lower priority for SwitchB so that SwitchB functions as the backup.

Procedure

Configure devices to ensure network connectivity.

# Assign an IP address to each interface. SwitchA is used as an example. The configurations of SwitchB and SwitchC are similar to the configuration of SwitchA. For details, see the configuration files.

<HUAWEI> system-view
[HUAWEI] sysname SwitchA
[SwitchA] vlan batch 100 300
[SwitchA] interface gigabitethernet 0/0/1
[SwitchA-GigabitEthernet0/0/1] port link-type hybrid
[SwitchA-GigabitEthernet0/0/1] port hybrid pvid vlan 300
[SwitchA-GigabitEthernet0/0/1] port hybrid untagged vlan 300
[SwitchA-GigabitEthernet0/0/1] quit
[SwitchA] interface gigabitethernet 0/0/2
[SwitchA-GigabitEthernet0/0/2] port link-type hybrid
[SwitchA-GigabitEthernet0/0/2] port hybrid pvid vlan 100
[SwitchA-GigabitEthernet0/0/2] port hybrid untagged vlan 100
[SwitchA-GigabitEthernet0/0/2] quit
[SwitchA] interface vlanif 100
[SwitchA-Vlanif100] ip address 10.1.1.1 24
[SwitchA-Vlanif100] quit
[SwitchA] interface vlanif 300
[SwitchA-Vlanif300] ip address 192.168.1.1 24
[SwitchA-Vlanif300] quit

# Configure Layer 2 transmission on the switch.

<HUAWEI> system-view
[HUAWEI] sysname Switch
[Switch] vlan 100
[Switch-vlan100] quit
[Switch] interface gigabitethernet 0/0/1
[Switch-GigabitEthernet0/0/1] port link-type hybrid
[Switch-GigabitEthernet0/0/1] port hybrid pvid vlan 100
[Switch-GigabitEthernet0/0/1] port hybrid untagged vlan 100
[Switch-GigabitEthernet0/0/1] quit
[Switch] interface gigabitethernet 0/0/2
[Switch-GigabitEthernet0/0/2] port link-type hybrid
[Switch-GigabitEthernet0/0/2] port hybrid pvid vlan 100
[Switch-GigabitEthernet0/0/2] port hybrid untagged vlan 100
[Switch-GigabitEthernet0/0/2] quit

# Configure OSPF between SwitchA, SwitchB, and SwitchC. SwitchA is used as an example. The configurations of SwitchB and SwitchC are similar to the configuration of SwitchA. For details, see the configuration files.

[SwitchA] ospf 1
[SwitchA-ospf-1] area 0
[SwitchA-ospf-1-area-0.0.0.0] network 10.1.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] network 192.168.1.0 0.0.0.255
[SwitchA-ospf-1-area-0.0.0.0] quit
[SwitchA-ospf-1] quit

Configure VRRP groups.

# Configure VRRP group 1 on SwitchA, and set the priority of SwitchA to 120 and the preemption delay to 20s.

[SwitchA] interface vlanif 100
[SwitchA-Vlanif100] vrrp vrid 1 virtual-ip 10.1.1.111
[SwitchA-Vlanif100] vrrp vrid 1 priority 120
[SwitchA-Vlanif100] vrrp vrid 1 preempt-mode timer delay 20
[SwitchA-Vlanif100] quit

# Configure VRRP group 1 on SwitchB. SwitchB uses default value 100.

[SwitchB] interface vlanif 100
[SwitchB-Vlanif100] vrrp vrid 1 virtual-ip 10.1.1.111
[SwitchB-Vlanif100] quit

Verify the configuration.

# After the configuration is complete, run the display vrrp command on SwitchA and SwitchB. You can see that SwitchA is in Master state and SwitchB is in Backup state.

[SwitchA] display vrrp
  Vlanif100 | Virtual Router 1
    State : Master
    Virtual IP : 10.1.1.111
    Master IP : 10.1.1.1
    PriorityRun : 120
    PriorityConfig : 120                                                        
    MasterPriority : 120                                                        
    Preempt : YES   Delay Time : 20 s
    TimerRun : 1 s
    TimerConfig : 1 s
    Auth type : NONE                                                            
    Virtual MAC : 0000-5e00-0101                                                
    Check TTL : YES                                                             
    Config type : normal-vrrp                                                   
    Backup-forward : disabled
    Create time : 2012-01-12 20:15:46
    Last change time : 2012-01-12 20:15:46

[SwitchB] display vrrp
  Vlanif100 | Virtual Router 1
    State : Backup
    Virtual IP : 10.1.1.111
    Master IP : 10.1.1.1
    PriorityRun : 100
    PriorityConfig : 100                                                        
    MasterPriority : 120                                                        
    Preempt : YES   Delay Time : 0 s
    TimerRun : 1 s
    TimerConfig : 1 s
    Auth type : NONE                                                            
    Virtual MAC : 0000-5e00-0101                                                
    Check TTL : YES                                                             
    Config type : normal-vrrp                                                   
    Backup-forward : disabled
    Create time : 2012-01-12 20:15:46
    Last change time : 2012-01-12 20:15:46

# Run the display ip routing-table command on SwitchA and SwitchB. The command output shows that a direct route to the virtual IP address exists in the routing table of SwitchA and an OSPF route to the virtual IP address exists in the routing table of SwitchB. The command output on SwitchA and SwitchB is as follows:

[SwitchA] display ip routing-table
Route Flags: R - relay, D - download to fib, T - to vpn-instance
------------------------------------------------------------------------------  
Routing Tables: Public                                                          
         Destinations : 9       Routes : 10                                    
                                                                                
Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface      
                                                                                
     10.1.1.0/24    Direct   0     0         D      10.1.1.1        Vlanif100
     10.1.1.1/32    Direct   0     0         D      127.0.0.1       Vlanif100
 10.1.1.111/32    Direct  0     0         D      127.0.0.1      Vlanif100
     127.0.0.0/8    Direct   0    0          D      127.0.0.1       InLoopBack0
    127.0.0.1/32    Direct   0    0          D      127.0.0.1       InLoopBack0
   172.16.1.0/24    OSPF     10   2          D      192.168.1.2     Vlanif300
  192.168.1.0/24    Direct   0    0          D      192.168.1.1     Vlanif300
  192.168.1.1/32    Direct   0    0          D      127.0.0.1       Vlanif300
  192.168.2.0/24    OSPF     10   2          D      10.1.1.2        Vlanif100
                    OSPF     10   2          D      192.168.1.2     Vlanif300

[SwitchB] display ip routing-table
Route Flags: R - relay, D - download to fib, T - to vpn-instance
------------------------------------------------------------------------------  
Routing Tables: Public                                                          
         Destinations : 9       Routes : 10                                    
                                                                                
Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface      
                                                                                
     10.1.1.0/24    Direct   0     0         D     10.1.1.2        Vlanif100
     10.1.1.2/32    Direct   0     0         D     127.0.0.1       Vlanif100
 10.1.1.111/32    OSPF    10    2         D     10.1.1.1      Vlanif100
     127.0.0.0/8    Direct   0     0         D     127.0.0.1       InLoopBack0
    127.0.0.1/32    Direct   0     0         D     127.0.0.1       InLoopBack0
   172.16.1.0/24    OSPF     10    2         D     192.168.2.2     Vlanif200
  192.168.1.0/24    OSPF     10    2         D     10.1.1.1        Vlanif100
                    OSPF     10    2         D     192.168.2.2     Vlanif200
  192.168.2.0/24    Direct   0     0         D     192.168.2.1     Vlanif200
  192.168.2.1/32    Direct   0     0         D     127.0.0.1       Vlanif200

# Run the shutdown command on GE0/0/2 of SwitchA to simulate a link fault.

[SwitchA] interface gigabitethernet 0/0/2
[SwitchA-GigabitEthernet0/0/2] shutdown
[SwitchA-GigabitEthernet0/0/2] quit

# Run the display vrrp command on SwitchB to view the VRRP status. The command output shows that SwitchB is in Master state.

[SwitchB] display vrrp
  Vlanif100 | Virtual Router 1
    State : Master
    Virtual IP : 10.1.1.111
    Master IP : 10.1.1.2
    PriorityRun : 100
    PriorityConfig : 100                                                        
    MasterPriority : 100                                                        
    Preempt : YES   Delay Time : 0 s
    TimerRun : 1 s
    TimerConfig : 1 s
    Auth type : NONE                                                            
    Virtual MAC : 0000-5e00-0101                                                
    Check TTL : YES                                                             
    Config type : normal-vrrp                                                   
    Backup-forward : disabled
    Create time : 2012-01-12 20:15:46
    Last change time : 2012-01-12 20:18:40

# Run the undo shutdown command on GE0/0/2 of SwitchA.

[SwitchA] interface gigabitethernet 0/0/2
[SwitchA-GigabitEthernet0/0/2] undo shutdown
[SwitchA-GigabitEthernet0/0/2] quit

# After 20s, run the display vrrp command on SwitchA to view the VRRP status. SwitchA restores the Master state.

[SwitchA] display vrrp
  Vlanif100 | Virtual Router 1
    State : Master
    Virtual IP : 10.1.1.111
    Master IP : 10.1.1.1
    PriorityRun : 120
    PriorityConfig : 120                                                        
    MasterPriority : 120                                                        
    Preempt : YES   Delay Time : 20 s
    TimerRun : 1 s
    TimerConfig : 1 s
    Auth type : NONE                                                            
    Virtual MAC : 0000-5e00-0101                                                
    Check TTL : YES                                                             
    Config type : normal-vrrp                                                   
    Backup-forward : disabled
    Create time : 2012-01-12 20:15:46
    Last change time : 2012-01-12 20:20:56

Configuration Files

SwitchA configuration file

#
sysname SwitchA
#
vlan batch 100 300
#
interface Vlanif100
 ip address 10.1.1.1 255.255.255.0
 vrrp vrid 1 virtual-ip 10.1.1.111
 vrrp vrid 1 priority 120
 vrrp vrid 1 preempt-mode timer delay 20
#
interface Vlanif300
 ip address 192.168.1.1 255.255.255.0
#
interface GigabitEthernet0/0/1
 port link-type hybrid
 port hybrid pvid vlan 300
 port hybrid untagged vlan 300
#
interface GigabitEthernet0/0/2
 port link-type hybrid
 port hybrid pvid vlan 100
 port hybrid untagged vlan 100
#
ospf 1
 area 0.0.0.0
  network 10.1.1.0 0.0.0.255
  network 192.168.1.0 0.0.0.255
#
return

SwitchB configuration file

#
sysname SwitchB
#
vlan batch 100 200
#
interface Vlanif100
 ip address 10.1.1.2 255.255.255.0
 vrrp vrid 1 virtual-ip 10.1.1.111
#
interface Vlanif200
 ip address 192.168.2.1 255.255.255.0
#
interface GigabitEthernet0/0/1
 port link-type hybrid
 port hybrid pvid vlan 200
 port hybrid untagged vlan 200
#
interface GigabitEthernet0/0/2
 port link-type hybrid
 port hybrid pvid vlan 100
 port hybrid untagged vlan 100
#
ospf 1
 area 0.0.0.0
  network 10.1.1.0 0.0.0.255
  network 192.168.2.0 0.0.0.255
#
return

SwitchC configuration file

#
sysname SwitchC
#
vlan batch 200 300 400
#
interface Vlanif200
 ip address 192.168.2.2 255.255.255.0
#
interface Vlanif300
 ip address 192.168.1.2 255.255.255.0
#
interface Vlanif400
 ip address 172.16.1.1 255.255.255.0
#
interface GigabitEthernet0/0/1
 port link-type hybrid
 port hybrid pvid vlan 300
 port hybrid untagged vlan 300
#
interface GigabitEthernet0/0/2
 port link-type hybrid
 port hybrid pvid vlan 200
 port hybrid untagged vlan 200
#
interface GigabitEthernet0/0/3
 port link-type hybrid
 port hybrid pvid vlan 400
 port hybrid untagged vlan 400
#
ospf 1
 area 0.0.0.0
  network 172.16.1.0 0.0.0.255
  network 192.168.1.0 0.0.0.255
  network 192.168.2.0 0.0.0.255
#
return

Switch configuration file

#
sysname Switch
#
vlan batch 100
#
interface GigabitEthernet0/0/1
 port link-type hybrid
 port hybrid pvid vlan 100
 port hybrid untagged vlan 100
#
interface GigabitEthernet0/0/2
 port link-type hybrid
 port hybrid pvid vlan 100
 port hybrid untagged vlan 100
#
return

Relevant Information

Video

Configuring VRRP