Configure stub areas to control external advertisements flooding and to minimize the size of the topological databases on an area's routers. A stub area cannot also be configured as an NSSA.
By default, summary route advertisements are sent into stub areas. The no form of the summary command disables sending summary route advertisements and only the default route is advertised by the ABR. This example retains the default so the command is not entered.
If this area is configured as a transit area for a virtual link, then existing virtual links of a non-stub or NSSA area are removed when its designation is changed to NSSA or stub.
Stub areas for OSPFv3 are configured the same as for OSPF.
Use the following syntax to configure an OSPF stub area.
ospf
area area-id
stub
default-metric metric
summaries
The following is a sample stub configuration output.
SAS-12>config>router>ospf>area># info
----------------------------------------------
...
area 0.0.0.0
exit
area 0.0.0.20
stub
exit
exit
...
----------------------------------------------
SAS-12>config>router>ospf#