Configuring Ospf Network Types - 3Com Switch 4800G 24-Port Configuration Manual

Prerequisites
Configuration Procedure
Configuring OSPF
Network Types
area, these LSAs will be translated into type 5 LSAs for advertisement to other
areas.
Non-backbone areas exchange routing information via the backbone area.
Therefore, the backbone and non-backbone areas, including the backbone itself
must maintain connectivity.
If necessary physical links are not available for this connectivity maintenance, you
can configure virtual links to solve it.
Before configuring an OSPF area, you have configured:
IP addresses for interfaces, making neighboring nodes accessible with each
■
other at the network layer.
OSPF basic functions.
■
Follow these steps to configure OSPF area parameters:
To do...
Enter system view
Enter OSPF view
Enter area view
Configure the area as a
stub area
Configure the area as an
NSSA area
Specify a cost for the
default route advertised to
the stub or NSSA area
Configure a virtual link
Advertise a host route
n
It is required to use the stub command on routers attached to a stub area.
■
It is required to use the nssa command on routers attached to an NSSA area.
■
Using the default-cost command only takes effect on the ABR of a stub area
■
or the ABR/ASBR of an NSSA area.
OSPF classifies networks into four types upon link layer protocols. Since an NBMA
network must be fully meshed, namely, any two routers in the network must have
a virtual link in between. In most cases, however, the requirement cannot be
satisfied, so you need to change the network type using commands.

Configuring OSPF Network Types

Use the command...
system-view
ospf [ process-id | router-id
router-id ] *
area area-id
stub [ no-summary ]
nssa [ default-route-advertise
| no-import-route |
no-summary ] *
default-cost cost
vlink-peer router-id [ hello
seconds | retransmit seconds |
trans-delay seconds | dead
seconds | simple [ plain |
cipher ] password | { md5 |
hmac-md5 } key-id [ plain |
cipher ] password ] *
host-advertise ip-address cost
295
Remarks
-
-
-
Optional
Not configured by default
Optional
Not configured by default
Optional
Defaults to 1.
Optional
Configured on both ends of a
virtual link
Note that hello and dead
parameters must be identical
on both ends of the link.
Optional
Not advertised by default