Multicast and Routing Guide K/KA/KB.15.15

which routes to select for either summarizing
or blocking.
For example, a range of 10.10.32.1/14
specifies all routes in the range of
10.10.32.1 - 10.10.35.254.
[no-advertise] Use this keyword only if you want to
configure the ABR to prevent advertisement
to the backbone of a specified range of
routes. (This has the effect of "hiding" the
specified range from the backbone area.)
If you do not use this option, the ABR
advertises the specified range of routes
according to the type summary | nssa
selection described below.
[type summary [[cost
1-16777215] | nssa ]]
Configures the type of route summaries to
advertise or block. If type is not used in the
command, the ABR defaults this setting to
summary.
type summary [[cost 1-16777215]]
Specifies internal routes in the configured
range of RAs. If no-advertise (above) is
used in the command, the ABR prevents the
selected internal routes from being
summarized in a type-3 LSA and advertised
to the backbone.
If no-advertise is not used in the
command, the selected routes are
summarized to the backbone in a type-3
LSA.
[cost 1-16777215]
User-configured cost for an area summary
range. If cost is specified, the range will
advertise the specified cost instead of the
calculated cost.
nssa Specifies
external routes
(type-7 LSAs) in
the configured
range of route
advertisements.
If
no-advertise
(above) is used
in the
command, the
ABR prevents
the selected
external routes
from being
summarized in
a type-5 LSA
Configuring ranges on an ABR to reduce advertising to the backbone 151