Enabling And Disabling Rpf Checks; Using Unicast Routes For Rpf - Juniper JUNOSE 11.1.X MULTICAST ROUTING Configuration Manual

Enabling and Disabling RPF Checks

By default, the router accepts multicast packets for each Source, Group (S,G) pair on
an incoming interface (IIF), which satisfies the RPF check (RPF-IIF). When the router
performs RPF checks, only the interface that first accepts traffic for an (S,G) pair
accepts subsequent traffic for that pair. If traffic stops arriving on that interface and
starts arriving on another interface, the router does not accept or forward the traffic.
Some network configurations require the router to accept traffic on any interface.
To do so, you can disable the RPF check on a specified set of (S,G) pairs by issuing
the ip multicast-routing disable-rpf-check command.
When you disable RPF checks, the router accepts multicast packets for (S,G) pairs
on any incoming interface. When the router has added the new route to its multicast
routing table, it then accepts multicast packets for these pairs on any interface in the
virtual router and forwards them accordingly. Multicast routes established before
you issue this command are not affected.
ip multicast-routing disable-rpf-check

Using Unicast Routes for RPF

You can specify that IS-IS, OSPF, or RIP routes be available for RPF. Routes available
for RPF appear in the multicast view of the routing table.
ip route-type
Prefix/Length Type
------------- ----
10.10.0.112/32 Static 192.168.1.1
See show ip rpf-route.
Use to disable RPF checks for specified (S,G) pairs.
Specify a standard IP access list that defines the (S,G) pairs.
Example
host1(config)#ip multicast-routing disable-rpf-check boston-list
Use the no version to restore the default, in which the router performs RPF
checks for all (S,G) pairs.
See ip multicast-routing disable-rpf-check.
Use to specify whether IS-IS, OSPF, or RIP routes are available only for unicast
forwarding, only for multicast RPF checks, or for both.
Use the show ip rpf-routes command to view the routes available for RPF.
By default, IS-IS, OSPF, and RIP routes are available both for unicast forwarding
and multicast reverse-path forwarding checks.
Chapter 1: Configuring IPv4 Multicast
Next Hop Dist/Met Intf
-------- -------- --------------
1/1 fastEthernet0/0

Enabling and Disabling RPF Checks

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