Configure An Ospf Area; Configure Ospf Area Parameters - Cabletron Systems SmartSwitch 8-slot User's Reference Manual

Chapter 5: OSPF Configuration Guide

Configure an OSPF Area

OSPF areas are a collection of subnets that are grouped in a logical fashion. These
areas communicate with other areas via the backbone area. Once OSPF areas are
created, you can add interfaces, stub hosts, and summary ranges to the area.
In order to reduce the amount of routing information propagated between areas, you
can configure summary-ranges on Area Border Routers (ABRs). On the SSR,
summary-ranges are created using the
specified using this command describe the scope of an area. Intra-area Link State
Advertisements (LSAs) that fall within the specified ranges are not advertised into
other areas as inter-area routes. Instead, the specified ranges are advertised as summary
network LSAs.
To create areas and assign interfaces, enter the following commands in the Configure
mode.
Create an OSPF area.
Add an interface to an OSPF area.
Add a stub host to an OSPF area.
Add a network to an OSPF area for
summarization.

Configure OSPF Area Parameters

The SSR allows configuration of various OSPF area parameters, including stub areas,
stub cost and authentication method. Stub areas are areas into which information on
external routes is not sent. Instead, there is a default external route generated by the
ABR, into the stub area for destinations outside the autonomous system. Stub cost
specifies the cost to be used to inject a default route into a stub area. An authentication
method for OSPF packets can be specified on a per-area basis.
5 - 4
ospf add network
ospf create area <area-num> |backbone
ospf add interface < name-or-IPaddr >
[to-area <area-addr> |backbone] [type
broadcast|non-broadcast]
ospf add stub-host [to-area <area-
addr> |backbone] [cost <num> ]
ospf add network <IPaddr/mask> [to-area
<area-addr> |backbone] [restrict] [host-
net]
command – the networks
SSR User Reference Manual