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Catalyst 3750-E and 3560-E Switch Software Configuration Guide
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Chapter42 Configuring IP Multicast Routing
Configuring IP Multicast Routing
In this example, the mapping agent accepts candidate RP a nnouncements from only two devices,
172.16.5.1 and 172.16.2.1. The mapping agent accepts ca ndidate RP announcements from these two
devices only for multicast groups that fall in the group range of 224.0.0.0 to 239.255.255.255. The
mapping agent does not accept candidate RP announcement s from any other devices in the network.
Furthermore, the mapping agent does not accept candidate RP announcements from 172.16.5.1
or 172.16.2.1 if the announcements are for any groups in the 239.0.0.0 through 239.2 55.255.255 range.
This range is the administratively scoped address range.
Configuring PIMv2 BSR
These sections describe how to set up BSR in your PIMv2 network:
•Defining the PIM Domain Border, page 42-20 (optional)
•Defining the IP Multicast Boundary, page 42-21 (optional)
•Configuring Candidate BSRs, page 42-22 (optional)
•Configuring Candidate RPs, page 42-23 (optional)
For overview information, see the “Bootstrap Router” section on page42-7.

Defining the PIM Domain Border

As IP multicast becomes more widespread, the chan ce of one PIMv2 domain bordering another PIMv2
domain is increasing. Because these two domains probably do no t share the same set of RPs, BSR,
candidate RPs, and candidate BSRs, you need to constrain PIM v2 BSR messages from flowing into or
out of the domain. Allowing these messages to leak across the domain borders could adversely affect the
normal BSR election mechanism and elect a single BSR a cross all bordering domains and co-mingle
candidate RP advertisements, resulting in the election of RPs in the wrong domain.
Beginning in privileged EXEC mode, follow these steps to define the PIM domain border. This
procedure is optional.
To remove the PIM border, use the no ip pim bsr-border interface configuration command.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface to be configured, and enter interface configuration
mode.
Step3 ip pim bsr-border Define a PIM bootstrap message boundary for the PIM domain.
Enter this command on each interface that connects to other bordering
PIM domains. This command instructs the switch to neither send or
receive PIMv2 BSR messages on this interface as shown in Figure42-4.
Step4 end Return to privileged EXEC mode.
Step5 show running-config Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.