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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 25 Configuring MSDP
Configuring MSDP
Controlling Source Information that Your Switch Forwards
By default, the multilayer switch forwards all SA messages it receives to all its MSDP peers. However,
you can prevent outgoing messages from being forwarded to a peer by using a filter or by setting a
time-to-live (TTL) value. These methods are described in the next sections.
Using a Filter
By creating a filter, you can perform one of these actions:
•
Filter all source/group pairs
•
Specify an IP extended access list to pass only certain source/group pairs
•
Filter based on match criteria in a route map
Beginning in privileged EXEC mode, follow these steps to apply a filter:
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
ip msdp sa-filter out ip-address | name
or
ip msdp sa-filter out {ip-address | name}
list access-list-number
or
ip msdp sa-filter out {ip-address | name}
route-map map-tag
Filter all SA messages to the specified MSDP peer.
or
To the specified peer, pass only those SA messages that pass the IP
extended access list. The range for the extended access-list-number
is 100 to 199.
If both the list and the route-map keywords are used, all conditions
must be true to pass any (S,G) pair in outgoing SA messages.
or
To the specified MSDP peer, pass only those SA messages that meet the
match criteria in the route map map-tag.
If all match criteria are true, a permit from the route map passes routes
through the filter. A deny filters routes.
