Brocade Multi-Service IronWare Multicast Configuration Guide (Supporting R05.6.00) User Manual

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Multi-Service IronWare Multicast Configuration Guide

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IP multicast boundaries

---------+-------------+----+---+------------------+---+---------+-------+-------

Interface|Local |Mode|Ver|Designated Router |TTL|Multicast| VRF | DR

---------+-------------+----+---+------------------+---+---------+-------+-------

v10 10.1.2.1 SM V2 Itself 1 None default 30

v30 123.1.1.2 SM V2 Itself 1 None

v40 124.1.1.2 SM V2 Itself 1 101

Syntax: show ip pim [ vrf vrf-name ] interface [ethernet slot/portnum | ve num | tunnel num ]

The vrf option allows you to display multicast boundary information for the VRF instance identified
by the vrf-name variable.

The ethernet port-number parameter specifies the physical port.

The ve num parameter specifies a virtual interface.

The tunnel num parameter specifies a GRE tunnel interface that is being configured. The GRE
tunnel interface is enabled under the device PIM configuration.

Performing IPv4 Multicast RPF shortcut using LSP paths

This feature provides the ability to run multicast IPv4 routing protocols (PIM-SM, SSM, PIM-DM)
using native IPv4 multicast forwarding when IGP (OSPF, IS-IS) shortcut feature or IPoMPLS is
enabled. When enabled, RPF (Reverse Path Forwarding) lookup results in a shortcut route (Label
Switched Path or LSP). Similarly RPF lookup results in a BGP route using MPLS tunnel or a static
route point to LSP end point. The LSP path resulted from these lookup cannot be directly used for
RPF operations in multicast. This feature aids in RPF path resolution when the RPF lookup results
in LSP.

When this feature is enabled, RPF lookup ignores the LSP route and uses the underlying native
route as the RPF path. In unicast routing the LSP path is used for forwarding. In multicast routing
the underlying native route is used.

FIGURE 2

LSP path topology

Figure 2

shows the RPF lookup to the source, which could result in the LSP paths between R1 and

R2. This feature uses native routes R1-R3-R2 and R1-R4-R2, and ECMP logic decides the RPF
shortcut.