Changing the shortest-path tree (SPT) operation

Generally, using the SPT option eliminates unnecessary levels of PIM-SM traffic in a domain. However, in cases where it is necessary to tightly control the paths used by PIM-SM flows to edge switches, disabling SPT maintains the flows through their original C-RPs regardless of whether shorter paths exist.


router pim spt-threshold

[no] router pim spt-threshold

When the router is the edge router for a receiver requesting to join a particular multicast group, this command enables or disables the capability of the router to convert the group's traffic from the RPT to the SPT.

See Restricting multicast traffic to RPTs.

(Default: Enabled)