[j-nsp] PIM RP stops working after 7.6->8.0 upgrade

[Jee Kay]

Hi all,

We're running a pair of M7is with 7.6R3.6 on them as our PIM RPs.
We've several other devices that register to them, in this specific
instance a pair of Cisco 3560Gs.

This setup has been working perfectly for a year or so, until we
upgraded to JunOS 8.0R3.4. As soon as we did that, any new sources
trying to register were stuck in Registering as though the RP was no
longer ACKing new registrations. This effectively prevented new
sources from joining the cloud.

A downgrade back to 7.6R3.6 fixed the problem immediately and all the
sources rejoined the cloud.

I've had a look through the release notes for 8.0R3.4 and the bits in
between there and 7.6 but can't find anything that looks like it would
explain this.

Has anyone else seen this behaviour and/or know what is causing it/how
to fix it?

Thanks in advance,
Ras