Dell S4048T, Руководство по настройке

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Open Shortest Path First (OSPFv2
and OSPFv3)
Open shortest path first (OSPFv2 for IPv4) and OSPF version 3 (OSPF for IPv6) are supported on Dell
Networking OS.
This chapter provides a general description of OSPFv2 (OSPF for IPv4) and OSPFv3 (OSPF for IPv6) as
supported in the Dell Networking Operating System (OS).
NOTE: The fundamental mechanisms of OSPF (flooding, DR election, area support, SPF calculations, and
so on) are the same between OSPFv2 and OSPFv3. This chapter identifies and clarifies the differences
between the two versions of OSPF. Except where identified, the information in this chapter applies to
both protocol versions.
OSPF protocol standards are listed in the Standards Compliance chapter.
Topics:
• Protocol Overview
• OSPF with Dell Networking OS
• Configuration Information
• Configuration Task List for OSPFv3 (OSPF for IPv6)
Protocol Overview
OSPF routing is a link-state routing protocol that calls for the sending of link-state advertisements (LSAs) to all
other routers within the same autonomous system (AS) areas.
Information on attached interfaces, metrics used, and other variables is included in OSPF LSAs. As OSPF
routers accumulate link-state information, they use the shortest path first (SPF) algorithm to calculate the
shortest path to each node.
OSPF routers initially exchange HELLO messages to set up adjacencies with neighbor routers. The HELLO
process is used to establish adjacencies between routers of the AS. It is not required that every router within
the AS areas establish adjacencies. If two routers on the same subnet agree to become neighbors through the
HELLO process, they begin to exchange network topology information in the form of LSAs.
In OSPFv2 neighbors on broadcast and NBMA links are identified by their interface addresses, while neighbors
on other types of links are identified by RID.
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