Github user revans2 commented on the issue:
https://github.com/apache/zookeeper/pull/453
@anmolnar I added in an updated version of the test in #310. The issue
turned out to be a race condition where the original leader would time out
clients and then would join the new quorum too quickly for the test to be able
to detect it. I changed it so there is a hard coded sleep instead and then
just shut down the leader. I would love to get rid of the hard coded sleep,
but I wasn't really sure how to do it without making some major changes in the
leader code to put in a synchronization point. If you really want me to do it
I can, but it felt rather intrusive.
I verified that when I comment out my code that does the fast forward the
test fails and when I put it back the test passes. If this looks OK I'll try
to port the test to the other release branches too.
I also addressed your request to make some of the code common.
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