3com S7906E Manuel De Montage

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Enabling OSPF 
You need to enable OSPF before you can perform other OSPF configuration tasks. 
Prerequisites 
Before configuring OSPF, you have configured the link layer protocol, and IP addresses for interfaces, 
making neighboring nodes accessible with each other at the network layer. 
Configuration Procedure 
To enable OSPF on a router, you need to create an OSPF process and specify areas with which the 
process is associated, and the network segments contained in each area. If an interface’s IP address 
resides on a network segment of an area, the interface belongs to the area and is enabled with OSPF, 
and OSPF advertises the direct route of the interface. 
To run OSPF, a router must have a Router ID, which is the unique identifier of the router in the AS. 
You can specify a Router ID when creating the OSPF process. Any two routers in an AS must have 
different Router IDs. In practice, the ID of a router is the IP address of one of its interfaces. 
If you specify no Router ID when creating the OSPF process, the global Router ID will be used. For 
details about global Router ID, refer to IP Routing Basics in the IP Routing Volume. You are 
recommended to specify a Router ID when creating the OSPF process. 
The system supports OSPF multi-process and OSPF multi-instance: 
When a router runs multiple OSPF processes, you need to specify a Router ID for each process, 
which takes effect locally and has no influence on packet exchange between routers. Therefore, 
two routers having different process IDs can exchange packets. 
You can configure an OSPF process to run in a specified VPN instance. 
Follow these steps to enable OSPF: 
To do… 
Use the command… 
Remarks 
Enter system view 
System-view 
— 
Enable an OSPF process and 
enter its view 
ospf [ process-id | 
router-id router-id | 
vpn-instance 
instance-name ] * 
Required 
Not enabled by default.