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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter22 Configuring IP Unicast Routing
Configuring OSPF
Note The OSPF area router configuration commands are all optional.
Beginning in privileged EXEC mode, follow these steps to configure area parameters:
Use the no form of these commands to remove the configured parameter value or to return to the
default value.
These are examples of outputs from the show ip ospf database and show ip ospf privileged EXEC
commands:
Switch # show ip ospf database
OSPF Router with ID (172.20.135.202) (Process ID 1)
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
172.20.135.202 172.20.135.202 455 0x80000009 0x83C2 1
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 router ospf process-id Enable OSPF routing, and enter router configuration mode.
Step3 area area-id authentication (Optional) Allow password-based protection against unauthorized
access to the identified area. The identifier can be either a decimal
value or an IP address.
Step4 area area-id authentication messa ge-dige st (Optional) Enable MD5 authentication on the area.
Step5 area area-id stub [no-summary] (Optional) Define an area as a stub area. The no-summary keyword
prevents an ABR from sending summary link advertisements into the
stub area.
Step6 area area-id nssa [no-redistribution]
[default-information-originate]
[no-summary]
(Optional) Defines an area as a not-so-stubby-area. Eve ry rout er
within the same area must agree that the area is NSSA. Select one of
these keywords:
•no-redistribution—Select when the router is an NSSA ABR and
you want the redistribute command to import routes into normal
areas, but not into the NSSA.
•default-information-originate—Select on an ABR to allow
importing type 7 LSAs into the NSSA.
•no-redistribution—Select to not send summary LSAs into the
NSSA.
Step7 area area-id range address mask (Optional) Specify an address range for wh ich a sing le route is
advertised. Use this command only with area border routers.
Step8 end Return to privileged EXEC mode.
Step9 show ip ospf [process-id]
show ip ospf [process-id [area-id]] database
Display information about the OSPF routing process in general or for
a specific process ID to verify configuration.
Display lists of information related to the OSPF database for a
specific router.
Step10 copy running-config startup-config (Optional) Save your entries in the configuration file.