3Com Switch 8800 Family Configuration Guide

316 CHAPTER 31: OSPF CONFIGURATION
By default, the type of imported route is type-2, the cost is 1 and the tag is 1 for a
imported route.
Configuring the default interval and number for OSPF to import external
routes
OSPF can import the external routing information and broadcast it to the entire
autonomous system. Importing routes too often and importing too many external
routes at one time will greatly affect the performance of the device. Therefore it is
necessary to specify the default interval and number for the protocol to import
external routes.
Perform the following configuration in OSPF view.
By default, the interval for importing external routes is 1 second. The upper limit to
the external routes imported is 1000 at a time.
Configuring OSPF to
Import Default Routes
By default, there are no default routes in a common OSPF area (either a backbone
area or a non-backbone area). Besides, the import-route command cannot be
used to import the default route.
Use the default-route-advertise command to generate and advertise a default
route in an OSPF route area. Note the following when you use this command:
■ If you use the default-route-advertise command on an ASBR or ABR of a
common OSPF area, the system generates a Type-5 LSA, advertising the default
route in the OSPF route area.
■ If you use the default-route-advertise command on an ASBR or ABR of an
NSSA, the system generates a Type-7 LSA, advertising the default route in the
NSSA.
■ This command is invalid for a stub area or a totally stub area.
Restore the default tag for the OSPF to import
external routes
undo default tag
Configure the default type of external routes
that OSPF will import
default type { 1 | 2 }
Restore the default type of the external routes
imported by OSPF
undo default type
Tabl e 277 Configure the default interval and number for OSPF to import external routes
Operation Command
Configure the default interval for OSPF to import external
routes
default interval seconds
Restore the default interval for OSPF to import external routes undo default interval
Configure the upper limit to the routes that OSPF imports at a
time
default limit routes
Restore the default upper limit to the external routes that can
be imported at a time
undo default limit
Table 276 Configure parameters for OSPF to import external routes
Operation Command