Filter
Top Products
DES-7200 Configuration Guide Chapter 4 OSPF
Configuration
4-14
4.2.6 Configuring the Route Aggregation
4.2.6.1 Configuring the Route Aggregation
between OSPF Areas
The ABR (Area Border Router) has at least two interfaces that belong to different
areas, one of which must be the backbone area. The ABR acts as the pivot in the
OSPF routing area, and it can advertise the routes of one area to another. If the
network addresses of the routes are continual in the area, the border router can
advertise only one aggregated route to other areas. The route aggregation
between areas greatly reduces the size of the routing table and improves the
efficiency of the network.
To configure the route aggregation between areas, execute the following
commands in the routing process configuration mode:
Command Function
DES-7200 (config-router)# area area-id
range ip-address mask [advertise |
not-advertise] [cost cost]
Configure route aggregation for the area.
Note
If route aggregation is configured, the detailed routes in this area will not be
advertised by the ABR to other areas.
4.2.6.2 Configuring the External Route
Aggregation
When the routes are redistributed from other routing process to the OSPF routing
process, every route is advertised to the OSPF-enabled router as a separate link
status. If the injected route is in the range of continuous IP addresses, the
autonomous area border router can advertise only one aggregated route, and
thus reducing the size of the routing table.
To configure the external route aggregation, execute the following commands in
the routing process configuration mode:
Command Function
DES-7200 (config-router)#
summary-address ip-address
mask[not-advertise | tag tag-id ]
Configure the external route aggregation.