Grafts to a multicast tree
Grafts to a multicast tree
A PIM device restores pruned branches to a multicast tree by sending graft messages towards the upstream device. Graft messages start at the leaf node and travel up the tree, first sending the message to its neighbor upstream device.
In the preceding example, if a new 229.255.0.1 group member joins on device R6, which was previously pruned, a graft is sent upstream to R4. Since the forwarding state for this entry is in a prune state, R4 sends a graft to R1. Once R4 has joined the tree, R4 along with R6 once again receive multicast packets.
Prune and graft messages are continuously used to maintain the multicast delivery tree. You do not need to configure anything.
84 | FastIron Ethernet Switch IP Multicast Configuration Guide |
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