area nssa
Use this command to set an area as a Not-So-Stubby-Area (NSSA). There are no external routes in an OSPF stub area, so you cannot redistribute from another protocol into a stub area. An NSSA allows external routes to be flooded within the area. These routes are then leaked into other areas. However, the external routes from other areas still do not enter the NSSA. You can configure an area to be a stub area or an NSSA, but not both.
This command simplifies administration when connecting a central site using OSPF to a remote site that is using a different routing protocol. You can extend OSPF to cover the remote connection by defining the area between the central router and the remote router as a NSSA.
Use the no form of this command to make an area a normal area.
Command Syntax
area (A.B.C.D|<0-4294967295>) nssa
area (A.B.C.D|<0-4294967295>) nssa {translator-role (candidate|always)|stability-interval <0-2147483647>|no-redistribution|default-information-originate (metric <0-16777214>|metric-type <1-2>|)|no-summary}
no area (A.B.C.D|<0-4294967295>) nssa
no area (A.B.C.D|<0-4294967295>) nssa {translator-role|stability-interval|no-redistribution|default-information-originate|no-summary}
Parameters
A.B.C.D
OSPF Area ID in IPv4 address format.
<0-4294967295>
OSPF Area ID as a decimal value.
translator-role
NSSA-ABR translator role:
candidate
Translate NSSA-LSA to Type-5 LSA if router is elected.
always
Always translate NSSA-LSA to Type-5 LSA.
stability-interval
Stability timer for a NSSA area. If an elected translator determines its services are no longer required, it continues to perform its duties for this time interval. This minimizes excess flushing of translated Type-7 LSAs and provides a more stable translator transition.
<0-4294967295>
Stability interval in seconds.
no-redistribution
Do not redistribute into the NSSA.
default-information-originate
Originate Type-7 default LSA into the NSSA.
metric
Specify metric for default routes.
<0-16777214>
Specify metric value.
metric-type
Specify metric type (see RFC 3101).
<1-2>
Specify metric type:
1: Type 1 external route
2: Type 2 external route
no-summary
Do not inject inter-area routes into the NSSA.
translate-candidate
Translate NSSA-LSA to Type-5 LSA if router is elected.
translate-always
Always translate NSSA-LSA to Type-5 LSA.
Default
By default, the nssa option value is candidate.
Command Mode
Router mode
Applicability
This command was introduced before OcNOS version 1.3.
Examples
(config)#router ipv6 ospf
(config-router)#area 3 nssa translator-role candidate no-redistribution default-information-originate metric 34 metric-type 2
Last modified date: 07-13-2023