3com S7906E Instruccion De Instalación

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announcements from other routers and organizes the information into an RP-set, which is flooded

throughout the entire network. Then, the other routers in the network calculate the mappings between

specific group ranges and the corresponding RPs based on the RP-set. We recommend that you

configure C-RPs on backbone routers.

To guard against C-RP spoofing, you need to configure a legal C-RP address range and the range of

multicast groups to be served on the BSR. In addition, because every C-BSR has a chance to become

the BSR, you need to configure the same filtering policy on all C-BSRs in the PIM-SM domain.

Follow these steps to configure a C-RP:

To do...

Use the command...

Remarks

Enter system view

system-view

—

Enter public instance PIM view
or VPN instance PIM view

pim [ vpn-instance
vpn-instance-name ]

—

Configure an interface to be a
C-RP

c-rp interface-type
interface-number [ group-policy
acl-number | priority priority |
holdtime hold-interval |
advertisement-interval
adv-interval ] *

Required

No C-RPs are configured
by default.

Configure a legal C-RP
address range and the range of
multicast groups to be served

crp-policy acl-number

Optional

No restrictions by default

When configuring a C-RP, ensure a relatively large bandwidth between this C-RP and the other

devices in the PIM-SM domain.

An RP can serve multiple multicast groups or all multicast groups. Only one RP can forward

multicast traffic for a multicast group at a moment.

Enabling auto-RP

Auto-RP announcement and discovery messages are addressed to the multicast group addresses

224.0.1.39 and 224.0.1.40 respectively. With auto-RP enabled on a device, the device can receive

these two types of messages and record the RP information carried in such messages.

Follow these steps to enable auto-RP: