Redundancy For Multicast Traffic - Cisco 7604 Configuration Manual

Configuring IPv4 Bidirectional PIM

Redundancy for Multicast Traffic

Redundancy for multicast traffic requires the following conditions:
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For additional information (including configuration examples and troubleshooting information), see the
Tip
documents listed on this page:
http://www.cisco.com/en/US/products/hw/routers/ps368/tsd_products_support_series_home.html
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
28-28
Unicast routing protocol such as OSPF or EIGRP
PIM uses RPF checks on the unicast routing table to determine the proper paths for multicast data
to traverse. If a unicast routing path changes, PIM relies upon the unicast routing protocol (OSPF)
to properly converge, so that the RPF checks used by PIM continue to work and show valid unicast
paths to and from the source IP address of the server sourcing the multicast stream.
PIM configured on all related Layer 3 interfaces
The unicast routing table is used to do path selection for PIM. PIM uses RPF checks to ultimately
determine the shortest path tree (SPT) between the client (receiver VLAN) and the source (multicast
VLAN). Therefore, the objective of PIM is to find the shortest unicast path between the receiver
subnet and the source subnet. You do not need to configure anything else for multicast when the
unicast routing protocol is working as expected and PIM is configured on all the Layer 3 links
associated with the unicast routing protocol.
Chapter 28 Configuring IPv4 Multicast Layer 3 Switching
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