OpenIndiana Distribution

Application joins 16 multicast groups using setsockopt() with IP_ADD_MEMBERSHIP option.
IGMPV2 Membership Reports are then issued by the O.S. for all 16 groups.
External IGMP Querier sees membership reports and data begins flowing on those IP addresses.
The data flowing happens to be HD video transport streams at 19.2 mbit/sec each - so there is a few hundred mbit/sec of
traffic involved.

External IGMP Querier does periodic IGMPV2 Membership Queries on the ALL-SYSTEMS address - 224.0.0.1
O.S. responds inconsistently with IGMP V2 Membership Reports to the group addresses it has previously joined.
For example, the O.S. may respond with Membership Reports for 70% of the groups that were joined originally.
As a result, the Querier stops the flow of data for the groups where there were no Membership Reports.

On the next Membership Query, the O.S. may respond with a different subset of Membership Reports.

We have deployed this exact scenario successfully on a snv111b platform.
We have not determined where in the chain between that and oi151a5 that it became broken.