Configuring gated
Configuring the OSPF Protocol
Defining Backbones
The OSPF backbone distributes routing information between areas. You can define backbones with the same statements and clauses as areas. You need not define the stub statement for a backbone. The backbone statement is used to define a router as a backbone router. If an OSPF internal or area boarder router is also a backbone router, the backbone statement must follow the area statements in the /etc/gated.conf file. Whenever you configure an area border router (a router connected to multiple areas), you must provide the backbone.
Figure 3-10 shows an example of two area border routers that form part of a backbone. Router A has interfaces to both area 0.0.0.1 and area 0.0.0.2, while router B has interfaces to areas 0.0.0.3 and 0.0.0.4. Router A is connected to router B through interface 15.13.115.156.
Figure 3-10 Backbone Configuration Example
Area 0.0.0.1 | Area 0.0.0.3 |
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Area 0.0.0.2 |
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The following is an example of the backbone router definition in router A’s /etc/gated.conf file:
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