[openib-general] RE: Failed multicast join withnew multicast module

[Sean Hefty]

>If this comment is directed at client reregister mechanism, you should
>note that when this was brought up there was resistance to it based on
>the recommendation (probably not a strong enough word for this) that SMs
>be redundant in the subnet. There was a fair bit of anecdotal evidence
>that this was not how they were being used at the time but it may have
>been a chicken and egg problem.

Even with redundant SMs, we wouldn't want them to reassign all of the LIDs in
the subnet just because of failover.  I don't think of MLIDs as being any
different.  Client reregister support is optional, so what if the node(s) that
need to re-create the group doesn't support it?

What if we started with something like the following compliance statement, and
tried to add this to the spec?

An SM, upon becoming the master, shall respect all existing communication in the
fabric, where possible.

- Sean