R0106-HP MSR Router Series Layer 3 - IP Routing Configuration Guide(V7)

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Ste
p
Command Remarks
3. Enable an OSPF process on
the interface.
ospf process-id area area-id
[ exclude-subip ]
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.
Configuring OSPF areas
Before you configure an OSPF area, complete 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, issue 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:
Ste
p
Command Remarks
1. Enter system view.
system-view
N/A
2. Enter OSPF view.
ospf [ process-id | router-id
router-id | vpn-instance
vpn-instance-name ] *
N/A
3. Enter area view.
area area-id N/A
4. Configure the area as a stub
area.
stub
[ default-route-advertise-always
| no-summary ] *
By default, no stub area is configured.
5. (Optional.) Specify a cost for
the default route advertised to
the stub area.
default-cost cost
The default setting is 1.
The default-cost cost command takes
effect only on the ABR of a stub area or
totally stub area.