3Com Switch 7750 Configuration Guide

492 CHAPTER 48: MSDP CONFIGURATION
Configuring a Rule for
Filtering the Multicast
Sources of SA Messages
An RP filters each registered source to control the information of active sources
advertised in the SA message. An MSDP peer can be configured to advertise only
the (S, G) entries in the multicast routing table that satisfy the filtering rule when
the MSDP creates the SA message; that is, to control the (S, G) entries to be
imported from the multicast routing table to the PIM-SM domain. If the
import-source command is executed without the acl keyword, no source will be
advertised in the SA message.
Configuring a Rule for
Filtering Received and
Forwarded SA Messages
Besides the creation of source information, controlling multicast source
information allows you to control the forwarding and reception of source
information. You can control the reception of SA messages using the MSDP
inbound filter (corresponding to the import keyword); you can control the
forwarding of SA messages by using either the MSDP outbound filter
(corresponding to the export argument) or the TTL threshold. By default, an
MSDP peer receives and forwards all SA messages.
MSDP inbound/outbound filter implements the following functions:
■ Filtering out all (S, G) entries
■ Receiving/forwarding only the SA messages permitted by advanced ACL rules
An SA message carrying encapsulated data can reach the specified MSDP peer
outside the domain only when the TTL in its IP header exceeds the threshold;
therefore, you can control the forwarding of SA messages that carry encapsulated
data by configuring the TTL threshold.
Configure to filter the SA
messages received by an
MSDP peer
peer peer-address
sa-request-policy [ acl
acl-number ]
Optional
By default, a router receives all
SA request messages from the
MSDP peer.
Table 389 Configure the transmission and filtering of SA request messages
Operation Command Description
Table 390 Configure a rule for filtering multicast sources using SA messages
Operation Command Description
Enter system view system-view -
Enter MSDP view msdp -
Configure to filter
multicast sources using
SA messages
import-source [ acl
acl-number ]
Optional
By default, all the (S, G) entries
in the domain are advertised in
the SA message.
Table 391 Configure a rule for filtering received and forwarded SA messages
Operation Command Description
Enter system view system-view -
Enter MSDP view msdp -