LevelOne GTL-2691 User Manual
Page 683
C
HAPTER
20
| Unicast Routing
Configuring the Open Shortest Path First Protocol (Version 2)
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A stub can have multiple ABRs or exit points. However, all of the exit
points and local routers must contain the same external routing data so
that the exit point does not need to be determined for each external
destination.
P
ARAMETERS
These parameters are displayed:
◆
Process ID – Process ID as configured in the Network Area
◆
Area ID – Identifier for a stub.
◆
Default Cost – Cost for the default summary route sent into a stub
from an area border router (ABR). (Range: 0-16777215; Default: 0)
Note that he the default cost is set to “0,” the router will not advertise a
default route into the attached stub.
◆
Summary – Controls the use of summary routes.
■
Summary – Allows an Area Border Router (ABR) to send a
summary link advertisement into the stub area.
■
No Summary – Stops an ABR from sending a summary link
advertisement into a stub area.
Routing table space is saved in a stub by blocking Type-4 AS
summary LSAs and Type 5 external LSAs. This option can be used
to completely isolate the stub by also stopping an ABR from sending
Type-3 summary LSAs that advertise the default route for
destinations external to the local area or the autonomous system.
Define an area as a totally stubby area only if routers in the area do
not require summary LSAs from other areas.
W
EB
I
NTERFACE
To configure protocol settings for a stub:
1.
Click Routing Protocol, OSPF, Area.
2.
Select Configure Area from the Step list.
3.
Select Configure Stub Area from the Action list.
4.
Select a Process ID, and modify the routing behavior for a stub.
5.
Click Apply