switch(ospf)# area 10 range 10.10.0.0/16 type nssa
You must execute
write mem
to preserve these settings across reboots.
Output showing settings for summary costs
The
show ip ospf
command displays information about summary costs. An entry of
auto
indicates that the
cost is calculated by the OSPF standard for summarized networks.
switch(config)# show ip ospf
OSPF Configuration Information
:
:
Currently defined address ranges:
Area ID LSA Type IP Network Network Mask Advertise Cost
--------------- ---------- --------------- --------------- --------- --------
0.0.0.10 Summary 10.10.0.0 255.255.0.0 yes auto
0.0.0.20 NSSA 10.20.0.0 255.255.0.0 yes auto
0.0.0.30 Summary 10.30.0.0 255.255.0.0 no 16777215
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
Allowing or blocking a range of external routes available through an ASBR
in an NSSA
Example of allowing or blocking a range of external RAs to the backbone
This example applies only to external routes that can be advertised from an NSSA to the backbone. The first
command defines the range of external routes in the Area 7 NSSA to advertise to the backbone. The second
command defines the range of external routes in the Area 7 NSSA to block from advertising to the backbone.
switch(config)# area 7 range 192.51.0.0/16 type nssa
switch(config)# area 7 range 192.51.0.0/16 no-advertise type nssa
Chapter 11 Open Shortest Path First Protocol (OSPF)
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