Example for Configuring Dynamic BFD for RIP

Procedure

1. Configure a VLAN for each interface.

   <HUAWEI> system-view
   [~HUAWEI] sysname SwitchA
   [*HUAWEI] commit
   [~SwitchA] vlan batch 10 20
   [*SwitchA] interface 10GE 1/0/1
   [*SwitchA-10GE1/0/1] port link-type trunk
   [*SwitchA-10GE1/0/1] port trunk allow-pass vlan 10
   [*SwitchA-10GE1/0/1] quit
   [*SwitchA] interface 10GE 1/0/2
   [*SwitchA-10GE1/0/2] port link-type trunk
   [*SwitchA-10GE1/0/2] port trunk allow-pass vlan 20
   [*SwitchA-10GE1/0/2] quit
   [*SwitchA] commit

   The configurations of Switch B, Switch C and Switch D are similar to the configuration of Switch A, and are not provided here.

2. Configure IP address for each VLANIF interface.

   [~SwitchA] interface vlanif 10
   [*SwitchA-Vlanif10] ip address 192.168.2.1 24
   [*SwitchA-Vlanif10] quit
   [*SwitchA] interface vlanif 20
   [*SwitchA-Vlanif20] ip address 192.168.3.1 24
   [*SwitchA-Vlanif20] quit
   [*SwitchA] commit

   The configurations of Switch B, Switch C and Switch D are similar to the configuration of Switch A, and are not provided here.

3. Configure basic RIP functions.

   # Configure Switch A.

   <SwitchA> system-view

   [~SwitchA] rip 1

   [*SwitchA-rip-1] version 2

   [*SwitchA-rip-1] network 192.168.4.0

   [*SwitchA-rip-1] network 192.168.3.0

   [*SwitchA-rip-1] quit

   [*SwitchA] commit

   # Configure Switch B.

   <SwitchB> system-view

   [~SwitchB] rip 1

   [*SwitchB-rip-1] version 2

   [*SwitchB-rip-1] network 192.168.4.0

   [*SwitchB-rip-1] network 192.168.4.0

   [*SwitchB-rip-1] network 172.16.0.0

   [*SwitchB-rip-1] quit

   [*SwitchB] commit

   # Configure Switch C.

   <SwitchC> system-view

   [~SwitchC] rip 1

   [*SwitchC-rip-1] version 2

   [*SwitchC-rip-1] network 192.168.3.0

   [*SwitchC-rip-1] network 192.168.4.0

   [*SwitchC-rip-1] quit

   [*SwitchC] commit

   # Configure Switch D.

   <SwitchD> system-view

   [~SwitchD] rip 1

   [*SwitchD-rip-1] version 2

   [*SwitchD-rip-1] network 172.16.0.0

   [*SwitchD-rip-1] quit

   [*SwitchD] commit

   # After completing the preceding operations, run the display rip neighbor command. The command output shows that Switch A, Switch B, and Switch C have established neighbor relationships with each other. In the following example, the display on Switch A is used.

   [~SwitchA] display rip 1 neighbor

   ---------------------------------------------------------------------           
    IP Address      Interface                   Type   Last-Heard   Routes         
   ---------------------------------------------------------------------           
    192.168.2.2     Vlanif10                    RIP    0:0:14            2         
    192.168.3.2     Vlanif20                    RIP    0:0:19            1         
   

   # Run the display ip routing-table command. The command output shows that the switches have imported routes from each other. In the following example, the display on Switch A is used.

   [~SwitchA] display ip routing-table

   Proto: Protocol        Pre: Preference
   Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
   ------------------------------------------------------------------------------  
   Routing Table: _public_                                                          
            Destinations : 12       Routes : 13                                    
                                                                                   
   Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface      
                                                                                   
         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    
       127.0.0.255/32  Direct  0    0           D   127.0.0.1       InLoopBack0    
        172.16.1.0/24  RIP     100  1           D   192.168.2.2     Vlanif10       
       192.168.2.0/24  Direct  0    0           D   192.168.2.1     Vlanif10       
       192.168.2.1/32  Direct  0    0           D   127.0.0.1       Vlanif10       
     192.168.2.255/32  Direct  0    0           D   127.0.0.1       Vlanif10       
       192.168.3.0/24  Direct  0    0           D   192.168.3.1     Vlanif20       
       192.168.3.1/32  Direct  0    0           D   127.0.0.1       Vlanif20       
     192.168.3.255/32  Direct  0    0           D   127.0.0.1       Vlanif20       
       192.168.4.0/24  RIP     100  1           D   192.168.3.2     Vlanif20       
                       RIP     100  1           D   192.168.2.2     Vlanif10       
   255.255.255.255/32  Direct  0    0           D   127.0.0.1       InLoopBack0

   The preceding command output shows that the next-hop address and outbound interface of the route to destination 172.16.1.0/16 are 192.168.2.2 and VLANIF10 respectively, and traffic is transmitted over the active link Switch A->Switch B.

4. Configure BFD in RIP processes.

   # Configure BFD on all interfaces of Switch A.

   [~SwitchA] bfd

   [*SwitchA-bfd] quit

   [*SwitchA] rip 1

   [*SwitchA-rip-1] bfd all-interfaces enable

   [*SwitchA-rip-1] bfd all-interfaces min-rx-interval 300 min-tx-interval 300 detect-multiplier 5

   [*SwitchA-rip-1] quit

   [*SwitchA] commit

   The configuration of Switch B is similar to that of Switch A, and is not provided here.

   # After completing the preceding operations, run the display rip bfd session command on Switch A. The command output shows that Switch A and Switch B have established a BFD session and the BFDState field value is displayed as Up. In the following example, the display on Switch A is used.

   [~SwitchA] display rip 1 bfd session all

    Interface :Vlanif10
    LocalIp       :192.168.2.1   RemoteIp  :192.168.2.2   BFDState  :Up
   
    Interface :Vlanif20
    LocalIp       :192.168.3.1   RemoteIp  :192.168.3.2   BFDState  :Down

5. Verify the configuration.

   # Run the shutdown command on 10GE1/0/0 of Switch B to simulate a fault in the active link.

   The link fault is simulated to verify the configuration. In actual situations, the operation is not required.

   [~SwitchB] interface 10GE 1/0/1

   [~SwitchB-10GE1/0/1] shutdown

   [*SwitchB-10GE1/0/1] commit

   # Check the routing table of Switch A.

   [~SwitchA] display ip routing-table

   Proto: Protocol        Pre: Preference
   Route Flags: R - relay, D - download to fib, T - to vpn-instance, B - black hole route
   ------------------------------------------------------------------------------  
   Routing Table: _public_                                                          
            Destinations : 9       Routes : 9                                    
                                                                                   
   Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface      
                                                                                   
         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    
       127.0.0.255/32  Direct  0    0           D   127.0.0.1       InLoopBack0    
        172.16.1.0/24  RIP     100  2           D   192.168.3.2     Vlanif20       
       192.168.3.0/24  Direct  0    0           D   192.168.3.1     Vlanif20       
       192.168.3.1/32  Direct  0    0           D   127.0.0.1       Vlanif20       
     192.168.3.255/32  Direct  0    0           D   127.0.0.1       Vlanif20       
       192.168.4.0/24  RIP     100  1           D   192.168.3.2     Vlanif20       
   255.255.255.255/32  Direct  0    0           D   127.0.0.1       InLoopBack0    

   The preceding command output shows that the standby link Switch A->Switch C->Switch B is used after the active link fails, and the next-hop address and outbound interface of the route to destination 172.16.1.0/16 are 192.168.3.2 and VLANIF20 respectively.