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Implementing OSPF on Cisco IOS XR Software
How to Implement OSPF on Cisco IOS XR Software
RC-149
Cisco IOS XR Routing Configuration Guide
Step 5
stub [no-summary]
or
nssa [no-redistribution]
[default-information-originate] [no-summary]
Example:
RP/0/RP0/CPU0:router(config-ospf-ar)# stub no
summary
or
RP/0/RP0/CPU0:router(config-ospf-ar)# nssa
no-redistribution
Defines the nonbackbone area as a stub area.
• See the “Configuring Stub and Not-so-Stubby Area
Types” section on page RC-147.
• Specify the no-summary keyword to further reduce the
number of LSAs sent into a stub area. This keyword
prevents the ABR from sending summary link-state
advertisements (Type 3) in the stub area.
or
Defines an area as an NSSA.
• See the “Configuring Stub and Not-so-Stubby Area
Types” section on page RC-147.
Step 6
stub
or
nssa
Example:
RP/0/RP0/CPU0:router(config-ospf-ar)# stub
or
RP/0/RP0/CPU0:router(config-ospf-ar)# nssa
(Optional) Turns off the options configured for stub and
NSSA areas.
• If you configured the stub and NSSA areas using the
optional keywords (no-summary, no-redistribution,
default-information-originate, and no-summary) in
Step 5, you must now reissue the stub and nssa
commands without the keywords—rather than using
the no form of the command.
• For example, the no nssa
default-information-originate form of the command
changes the NSSA area into a normal area that
inadvertently brings down the existing adjacencies in
that area.
Step 7
default-cost
cost
Example:
RP/0/RP0/CPU0:router(config-ospf-ar)#
default-cost 15
(Optional) Specifies a cost for the default summary route
sent into a stub area or an NSSA.
• Use this command only on ABRs attached to the NSSA.
Do not use it on any other routers in the area.
• The default cost is 1.
Command or Action Purpose