Cisco Systems ME 3400 Configuring IP Multicast Routing

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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide

OL-9639-06

Chapter 40 Configuring IP Multicast Routing

Configuring IP Multicast Routing

PIM uses both source trees and RP-rooted shared trees to forward datagrams (described in the “PIM

DM” section on page 40-4 and the “PIM SM” section on page 40-4). The RPF check is performed

differently for each:

• If a PIM router or multilayer switch has a source-tree state (that is, an (S,G) entry is present in the

multicast routing table), it performs the RPF check against the IP address of the source of the

multicast packet.

• If a PIM router or multilayer switch has a shared-tree state (and no explicit source-tree state), it

performs the RPF check on the RP address (which is known when members join the group).

Sparse-mode PIM uses the RPF lookup function to decide where it needs to send joins and prunes:

• (S,G) joins (which are source-tree states) are sent toward the source.

• (*,G) joins (which are shared-tree states) are sent toward the RP.

Dense-mode PIM uses only source trees and use RPF as previously described.

Configuring IP Multicast Routing

These sections contain this configuration information:

• Default Multicast Routing Configuration, page 40-8

• Multicast Routing Configuration Guidelines, page 40-9

• Configuring Basic Multicast Routing, page 40-10 (required)

• Configuring PIM Stub Routing, page 40-12 (optional)

• Configuring Source-Specific Multicast, page 40-13

• Configuring Source Specific Multicast Mapping, page 40-17

• Configuring a Rendezvous Point, page 40-22 (required if the interface is in sparse-dense mode, and

you want to treat the group as a sparse group)

• Using Auto-RP and a BSR, page 40-32 (required for non-Cisco PIMv2 devices to interoperate with

Cisco PIM v1 devices))

• Monitoring the RP Mapping Information, page 40-33 (optional)

• Troubleshooting PIMv1 and PIMv2 Interoperability Problems, page 40-33 (optional)

Table 40-2 shows the default multicast routing configuration.

Tab le 40-2 Default Multicast Routing Configuration

Feature Default Setting

Multicast routing Disabled on all interfaces.

PIM version Version 2.

PIM mode No mode is defined.

PIM RP address None configured.

PIM domain border Disabled.