Document ID: RDWR-ALOS-V2900_AG1302
137
Chapter 11 – Open Shortest Path First (OSPF)
Alteon supports versions 2 and 3 of the Open Shortest Path First (OSPF) routing protocol.
The Alteon OSPF version 2 implementation conforms to the specifications detailed in Internet
RFC 1583.
The Alteon OSPF version 3 implementation conforms to the specifications detailed in Internet
RFC 2740.
The following topics are addressed in this chapter:
•
—This section explains OSPF concepts, such as types of OSPF areas,
types of routing devices, neighbors, adjacencies, link state database, authentication, and
internal versus external routing.
•
—This section describes how OSPF is implemented, such as
configuration parameters, electing the designated router, summarizing routes, and defining
route maps.
•
OSPF Configuration Examples, page 150
—This section provides step-by-step instructions on
configuring four different configuration examples:
—
Example 1: Simple OSPF Domain, page 151
—
Example 2: Virtual Links, page 152
—
Example 3: Summarizing Routes, page 156
—
Example 4: Host Routes, page 158
Note:
CLI command paths in this chapter reflect OSPF version 2. For OSPF version 3 paths, it is
sufficient in most cases to replace the ospf parameter with ospfv3. For example:
•
OSPF version 2 CLI path:
•
Corresponding OSPF version 3 CLI path:
OSPF Overview
OSPF is designed for routing traffic within a single IP domain called an Autonomous System (AS).
The AS can be divided into smaller logical units known as areas.
All routing devices maintain link information in their own Link State Database (LSDB). The LSDB for
all routing devices within an area is identical but is not exchanged between different areas. Only
routing updates are exchanged between areas, thereby significantly reducing the overhead for
maintaining routing information on a large, dynamic network.
The following key OSPF concepts are described in this section:
•
Equal Cost Multipath Routing Support, page 138
•
•
Types of OSPF Routing Devices, page 139
•
Neighbors and Adjacencies, page 139
•
The Link-State Database, page 140
>> # /cfg/l3/
ospf
/aindex
>> # /cfg/l3/
ospfv3
/aindex