Subject: Pruning too much for long-lived sessions

From: Carsten Bormann <[email-masked]>
Date: 13 Mar 1997 20:01:02 +0100

Can someone please remind me of the exact cause of the following problem:

Within a very long-running multicast session, packets from particular
senders only arrive every few minutes or so.  It seems that some
routers on the way from those members to here regularly prune back on
the trees to here as if there was no downstream member (but we aren't
sending prunes -- we are a multicast group member and receive other
senders nicely).

Something on these lines was discussed some time ago in the mbone
mailing list (I tend to believe it involved PIM/DVMRP interworking and
non-recent versions of cisco code) -- does anyone remember?

Alternatively, does anyone know a good way to debug such a situation
using mtrace etc.?

Gruesse, Carsten

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From: Bill Fenner <[email-masked]>
Date: Thu, 13 Mar 1997 16:34:56 PST

>Alternatively, does anyone know a good way to debug such a situation

Sure, use "mtrace -l source group" and watch where packet loss occurs.

  Bill