H3C Technologies H3C SR8800 - Manual (Page 97)

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Step Command Remarks
3. Enable an OSPF process
and enter OSPF view.
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
Not enabled by default.
4. Configure a description for
the OSPF process.
description description
Optional.
Not configured by default.
5. Configure an OSPF area
and enter OSPF area view. area area-id
Not configured by default.
6. Configure a description for
the area.
description description
Optional.
Not configured by default.
7. Specify a network to enable
OSPF on the interface
attached to the network.
network ip-address
wildcard-mask
Not configured by default.
NOTE:
•
A network segment can belong to only one area.
• Configure a description for each OSPF process to help identify purposes of processes and for ease of
management and memorization.
• Configure a description for each area to help identify purposes of areas and for ease of management
and memorization.
Configuring OSPF areas
After you split an OSPF AS into multiple areas, you can further configure some areas as stub areas or
NSSA areas as needed.
If no connection can be achieved between the backbone and a non-backbone area, or within the
backbone itself, you can configure virtual links to solve it.
Configuration prerequisites
Before you configure an OSPF area, complete the following tasks:
• Configure IP addresses for interfaces, and make sure that all neighboring nodes are reachable to
each other at the network layer.
• Enable OSPF.
Configuring a stub area
You can configure a non-backbone area at the AS edge as a stub area by configuring the stub command
on all the routers attached to the area. In this way, Type-5 LSAs will not be flooded within the stub area,
reducing the routing table size. The ABR generates a default route into the stub area so that all packets
destined outside of the AS are sent through the default route.
To further reduce the routing table size and routing information exchanged in the stub area, configure it
as a totally stub area by using the stub [ no-summary ] command on the ABR. In this way, neither AS
external routes nor inter-area routing information will be distributed into the area. All the packets destined
outside of the AS or area will be sent to the ABR for forwarding.