3Com 4007R Implementation Guide - Page 449
OSPF interfaces, Link state databases, Neighbors, Router IDs, OSPF memory partition
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Page 449 highlights
OSPF Overview 449 s OSPF interfaces - An OSPF interface is an IP interface that you configure to send and receive OSPF traffic. When you configure an OSPF interface, you define the behavior and role of the interface within the OSPF routing domain. For example, router priority determines designated router selection, cost determines the expense associated with using the interface, and the Hello interval directly affects how fast topological changes are detected. For more information, see "OSPF Interfaces" later in this chapter. s Link state databases - OSPF routers advertise routes using link state advertisements. The link state database contains the link state advertisements from throughout the area to which an OSPF interface is attached. For more information, see "Link State Databases" later in this chapter. s Neighbors - OSPF interfaces attached to a common network are called neighbors; adjacent neighbors exchange link state database information. On broadcast networks, neighbors are discovered dynamically using the Hello protocol. On nonbroadcast multiaccess networks, you must statically configure neighbors. Your system allows you to display all neighbors in the locality of the router, as well configure them when needed. For more information, see "Neighbors" later in this chapter. s Router IDs - A router ID identifies the router to other routers within the autonomous system. In addition, it serves as a tie-breaker in the designated router election. You systems gives you three methods by which you can configure a router ID for an OSPF interface. For more information, see "Router IDs" later in this chapter. s OSPF memory partition - You can display how much memory your system allocates for OSPF data processing and adjust this memory allocation if needed. For more information, see "OSPF Memory Partition" later in this chapter. s Stub default metrics - External link state advertisements are not propagated into stub areas. Instead, the area border router for a stub area injects a single external default route into the area. Your system allows you to configure an area border router to advertise a single external default route into the stub area while specifying the cost of the default route. For more information, see "Stub Default Metrics" later in this chapter.
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