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Step
2.
Enter interface view.
3.
Enable an OSPF process
on the interface.
Configuring OSPF areas
Before you configure an OSPF area, perform the following tasks:
•
Configure IP addresses for interfaces to ensure IP connectivity between neighboring nodes.
•
Enable OSPF.
Configuring a stub area
You can configure a non-backbone area at an AS edge as a stub area. To do so, execute the stub
command on all routers attached to the area. The routing table size is reduced because Type-5 LSAs
will not be flooded within the stub area. The ABR generates a default route into the stub area so 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
a totally stub area by using the stub no-summary command on the ABR. AS external routes and
inter-area routes will not be distributed into the area. All the packets destined outside of the AS or
area will be sent to the ABR for forwarding.
A stub or totally stub area cannot have an ASBR because external routes cannot be distributed into
the area.
To configure an OSPF stub area:
Step
1.
Enter system view.
2.
Enter OSPF view.
3.
Enter area view.
4.
Configure the area as a
stub area.
5.
(Optional.) Set a cost for
the default route advertised
to the stub area.
Command
interface interface-type
interface-number
ospf process-id area
area-id [ exclude-subip ]
Command
system-view
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
area area-id
stub
[ default-route-advertise-alwa
ys | no-summary ] *
default-cost cost-value
75
Remarks
N/A
By default, OSPF is disabled on an
interface.
If the specified OSPF process and area do
not exist, the command creates the OSPF
process and area. Disabling an OSPF
process on an interface does not delete the
OSPF process or the area.
Remarks
N/A
N/A
N/A
By default, no stub area is configured.
The default setting is 1.
The default-cost cost command
takes effect only on the ABR of a stub
area or totally stub area.
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Troubleshooting
