Cisco NCS 5500 Series

advertises to another area. Such summarization would reduce the number of LSAs and thereby conserve
network resources. This summarization is known as interarea route summarization. It applies to routes from
within the autonomous system. It does not apply to external routes injected into OSPF by way of redistribution.
This task configures OSPF to summarize subnetworks into one LSA, by specifying that all subnetworks that
fall into a range are advertised together. This task is performed on an ABR only.
SUMMARY STEPS
1. configure
2. Do one of the following:
• router ospf process-name
• router ospfv3 process-name
3. router-id { router-id }
4. area area-id
5. Do one of the following:
• range ip-address mask [ advertise | not-advertise ]
• range ipv6-prefix / prefix-length [ advertise | not-advertise ]
6. interface type interface-path-id
7. commit
DETAILED STEPS
Step 1 configure
Step 2 Do one of the following:
• router ospf process-name
• router ospfv3 process-name
Example:
RP/0/RP0/CPU0:router(config)# router ospf 1
or
RP/0/RP0/CPU0:router(config)# router ospfv3 1
Enables OSPF routing for the specified routing process and places the router in router configuration mode.
or
Enables OSPFv3 routing for the specified routing process and places the router in router ospfv3 configuration mode.
The process-name argument is any alphanumeric string no longer than 40 characters.
Note
Step 3 router-id { router-id }
Example:
RP/0/RP0/CPU0:router(config-ospf)# router-id 192.168.4.3
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
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Implementing OSPF
Summarize Subnetwork LSAs on OSPF ABR