How does a Huawei router establish an OSPF network?

OSPF is also known as the interface status routing protocol. It establishes a link status database by notifying the status of network interfaces between routers to generate a shortest path tree. Each OSPF router uses these Shortest Paths to construct a route table, OSPF will send a HELLO packet on the network. If there are three matching items in the HELLO packet, a neighbor relationship will be established. First, the HELLO packet's death and update time, Region ID, there is also an authentication field.

In a point-to-point network, an adjacent router establishes a neighbor by sending a HELLO packet. After a neighbor is established, it can send update data packets such as LSA and lsr lsu dbd, in a multi-channel access network, the DR and BDR are established through the HELLO packet. The router only establishes a neighbor relationship with the DR and BDR, sends and updates the LSA, and maintains the detected two-away state with other routers.

1. Configure OSPF in the network set up by the Huawei router. The two routers, Huawei A and Huawei B, are in the same region. The IP address of Huawei A is 13.15.32.25/16, the router-id is 1.1.1.1, the IP address of Huawei B is 13.15.32.35/24, and the router-id is 2.2.2.2. It is in the same network segment as Huawei A, and the OSPF process of both ports is 1, after the configuration is complete, it is found that OSPF neighbors cannot reach the FULL state.

Ii. Analyze the faults below

1. Configure the ports of Huawei A and Huawei B respectively. Huawei A and Huawei B adopt the same configuration, except that the router-id is changed to 2.2.2.2.

2. Execute the display ospf peer command on Huawei A to check the neighbor relationship between Huawei A and Huawei B. It is found that OSPF neighbors cannot reach the FULL state.

3. Run the display current-configuration interface GigabitEthernet 1/0/1 command on Huawei A to find that the IP address of the Huawei A interface is 13.15.32.25 with A 24-bit mask.

4. Execute the display current-configuration ospf command on Huawei A and find that the address mask released by OSPF is 25 bits. The RFC description requires that the following two conditions be met, the OSPF protocol can be run normally on the interface. First, the IP Address Mask Length of the interface is greater than or equal to the mask length in the network command. Second, the main IP address of the interface must be within the network segment specified by the network command.

5. Therefore, we found that the IP Address Mask Length of the interfaces of Huawei A is 24, while the interface Address Mask Length released in OSPF is 25, which is greater than the Mask Length of the interface IP address of Huawei, therefore, OSPF neighbors cannot reach the FULL state after the configuration is complete.

3. In this case, we only need to enter the two routers, configure the network segments included in the region in the OSPF region, and save the modifications to the configuration. After the operation is completed, OSPF is in the FULL state and troubleshooting is enabled.

After the above introduction, we can understand the main points of the RFC that meet the requirements of the OSPF protocol when performing basic OSPF configuration.