Allowing or blocking advertisement of a range of internal routes available in an area by an ABR

Defining a range of internal routes to advertise to the backbone

The commands in this example define the same range of internal routes in area 30 to summarize for injection into the backbone area. (In this example, area 30 can be a normal or stub area, or an NSSA.)

switch(ospf)# area 30 range 10.0.0.0/8
switch(ospf)# area 30 range 10.0.0.0/8 type summary

Defining a range of internal routes to block from advertising to the backbone

For the same range of routes, you can use either of the following commands to block injection of a range of summary routes (type-3 LSAs) from area 30 into the backbone.

switch(config)# area 30 range 10.0.0.0/8 type no-advertise
switch(config)# area 30 range 10.0.0.0/8 type no-advertise summary