3Com Switch 8800 Configuration Guide
Chapter 19 OSPF Configuration
19-12
z
The broadcasting scope of Type-5 LSA or Type-7 LSA advertising the default
route is the same as that of the common Type-5 LSA or Type-7 LSA.
Perform the following configuration in OSPF view.
Table 19-8
Configure OSPF to import the default route
Operation
Command
Import the default route to
OSPF
default-route-advertise
[
always
|
cost
value
|
type
type
-
value
|
route-policy
route
-
policy
-
name
]*
Remove the imported
default route
undo default-route-advertise
[
always
|
cost
|
type
|
route-policy
]*
By default, OSPF does not import the default route.
If you use the
always
keyword of this command, the system will generate a Type-5 or
Type-7 LSA no matter whether there is default route in the routing table. Be cautious
that the
always
keyword is only valid for an ASBR.
Because OSPF does not calculate the LSAs it generated during SPF calculation, there
is no default route in the OSPF route on this router. To ensure the correct routing
information, you should configure to import the default route on the router only
connected to the external network.
Note:
z
After the
default-route-advertise
command is configured on the OSPF router, this
router becomes an ASBR. For the OSPF router, the
default-route-advertise
and
import-route
commands have the similar effect.
z
For the ABR or ASBR in the NSSA area, the
default-route-advertise
and
nssa
default-route-advertise
commands have the same effect.
19.2.7 Configuring OSPF Route Filtering
Perform the following configuration in OSPF view.
I. Configuring OSPF to filter the received routes
Table 19-9
Enable OSPF to filter the received routes
Operation
Command
Disable filtering the received
global routing information
filter-policy
{
acl
-
number
|
ip-prefix
ip
-
prefix
-
name
|
gateway
ip
-
prefix
-
name
}
import
Cancel filtering the received
global routing information
undo filter-policy
{
acl
-
number
|
ip-prefix
ip
-
prefix
-
name
|
gateway
ip
-
prefix
-
name
}
import
