Example for Configuring OSPF GTSM

Procedure

1. Configure an IP address for each interface.

   # Configure IP addresses for all interfaces of RouterA.

   <Huawei> system-view
   [Huawei] sysname RouterA
   [RouterA] interface gigabitethernet 1/0/0
   [RouterA-GigabitEthernet1/0/0] ip address 192.168.1.1 255.255.255.0
   [RouterA-GigabitEthernet1/0/0] quit
   [RouterA] interface gigabitethernet 2/0/0
   [RouterA-GigabitEthernet2/0/0] ip address 192.168.2.1 255.255.255.0
   [RouterA-GigabitEthernet2/0/0] quit
   [RouterA] interface gigabitethernet 3/0/0
   [RouterA-GigabitEthernet3/0/0] ip address 10.1.1.1 255.0.0.0.0
   [RouterA-GigabitEthernet3/0/0] quit

   The configurations of RouterB, RouterC and RouterD are similar to the configuration of RouterA, and are not mentioned here.

2. Configure basic OSPF functions (see Example for Configuring Basic OSPF Functions).
3. Configure OSPF GTSM.

   # On RouterA, set the maximum valid TTL range for packets from RouterA to other routers is 255 to 255.

   [RouterA] ospf valid-ttl-hops 1

   # On RouterB, set the maximum valid TTL range for packets from RouterB to other routers is 254 to 255.

   [RouterB] ospf valid-ttl-hops 2

   # On RouterC, set the maximum valid TTL range for packets from RouterC to other routers is 254 to 255.

   [RouterC] ospf valid-ttl-hops 2

4. Verify the configuration.

   # Check whether OSPF neighbor relationships between routers are successfully established. Take the display of RouterC as an example. The neighbor relationship is Full, indicating that the neighbor relationship is successfully established.

   [RouterC] display ospf peer

             OSPF Process 1 with Router ID 3.3.3.3

                     Neighbors

    Area 0.0.0.0 interface 192.168.2.2(GigabitEthernet2/0/0)'s neighbors

   Router ID: 1.1.1.1      Address: 192.168.2.1

   State: Full  Mode:Nbr is  Master  Priority: 1

      DR: 192.168.2.2   BDR: 192.168.2.1   MTU: 0

      Dead timer due in 36  sec

      Retrans timer interval: 5

      Neighbor is up for 00:15:04

      Authentication Sequence: [ 0 ]

   # On Router C, run the display gtsm statistics all command. You can view GTSM statistics on RouterC. The default behavior is pass, no illegal packets exist, and the number of discarded packets is 0.

   <RouterC> display gtsm statistics all

   GTSM Statistics Table

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   SlotId  Protocol  Total Counters  Drop Counters  Pass Counters

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    0      BGP       0               0              0
    0      BGPv6     0               0              0
    0      OSPF      0               0              0
    0      LDP       0               0              0
    1      BGP       0               0              0
    1      BGPv6     0               0              0
    1      OSPF      0               0              0
    1      LDP       0               0              0
    2      BGP       0               0              0
    2      BGPv6     0               0              0
    2      OSPF      0               0              0
    2      LDP       0               0              0
    3      BGP       0               0              0
    3      BGPv6     0               0              0
    3      OSPF      0               0              0
    3      LDP       0               0              0
   

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