RFC 4601, "Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)", August 2006
Note: This RFC has been obsoleted by RFC 7761Source of RFC: pim (rtg)
Errata ID: 1160
Status: Held for Document Update
Publication Format(s) : TEXT
Reported By: Maren Peasley
Date Reported: 2007-12-21
Held for Document Update by: David Ward
Date Held: 2009-03-22
Section 4.5.4 says:
Receive Prune(S,G,rpt) The compound Join/Prune message contains a Prune(S,G,rpt). The (S,G,rpt) downstream state machine on interface I transitions back to the Prune-Pending state. The Expiry Timer (ET) is restarted, set to maximum of its current value and the HoldTime from the triggering Join/Prune message.
It should say:
Infinite toggle for every pair of routers where one wants (*,G) and the other wants (*,G) and (S,G,rpt). State moves from Prune -> PruneTmp -> NI -> Prune for the (S,G,rpt) state machine. This causes upstream thrash with Join(S,G,rpt) followed by Prune(S,G,rpt) in continual succession. Which causes Prune (S,G,rpt) state to be state limited to never actually enter Prune state (NI -> PP -> NI).