Cabletron Systems CoreWatch, User Manual

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Chapter 16: Configuring Routing Policies on the SSR
330 CoreWatch User’s Manual
8. Specify a name four your aggregate source in the
Aggregate Source
box.
9. From the Route Protocol drop-down list, select the protocol of the contributing
aggregate source.
10. Do one of the following to specify which method of route restriction you wish to use:
– To restrict selection of routes to those learned from the specified autonomous
system, select the
Learned from AS option and then enter a number from 1 to 65534
in the associated text box.
This selection may also be carried out by using route filters to explicitly list the set
of routes to be accepted.
– To restrict the selection of routes to those identified by a tag, select the Having Tag
option and specify the desired tag in the associated text box.
– To restrict selection of routes to those specified by the autonomous-system path,
select the
AS Path Matching option and specify the appropriate path in the
associated text box.
– To allow unrestricted route selection, select the none option.
This selection may also be carried out by using route filters.
11. Specify whether the routes are to be considered as contributors to the aggregate
source by turning the Resulting routes are not part of this aggregate option on or off.
12. If the routes are to be considered as contributors of the aggregate source, specify the
preference to assign to the contributing routes by entering a number from 0 to 255 in
the
Route Preference box.
13. Click OK .
14. Repeat step 8 through step 13 until you create all of the aggregate sources you plan to
include in your aggregate policies.
IP Route Filter Building Blocks
The SSR uses IP route filters to match a certain set of routes by destination or by
destination and mask. You define IP route filters by specifying a destination, mask, and
modifiers that specify which routes the filter is for.
Note:
A route will match the most specific filter that applies. Specifying more than one
filter with the same destination, mask, and modifiers will generate an error.
The method you use to define an IP route filter depends on whether you are creating a
new filter or modifying an existing one. Separate discussions on these tasks follow.