Hi All,

I think I am noticing what appears to be an anomaly, so just posting here for 
sanity check.

We have a stress test that does frequent network partitioning/reunification to 
exercise code related to node fail-back. We're based on version 1.4.6. We were 
were based on 2.x.x until libqb made its way into the core of corosync. As our 
company policy precludes us from using anything but BSD style licensed third 
part source code, we had to either rewrite libqb or go back.

Lets's say we have four nodes A, B, C and D. A and B are one side of a network 
segment and C and D on the other. The network can be partitioned by pulling a 
cable connecting the two segments.

When there is a configuration change, we need to re-compute application state 
by sending messages to the new members. Such a message identifies the 
originating node and the size of the cluster at the time. And this message is 
logged in application log. 


When the cluster goes from A,B,C,D to (A,B) and (C, D), on A-B side, we see 
message from A that says "From A, cluster size is 2". Immediately thereafter 
there's another config. chage  to take the cluster back to (A, B, C, D). Now we 
see messages from A, C and D that the cluster size is 4. But we see two 
messages from B, the first one says the cluster size is 2 and the second one 
says it's 4. It appears that the message from B when the cluster size was 2, 
could not be delivered as there was a config. change right on its heel, but 
it's being delivered to a configuration different from the one where it 
originated. Is this expected behaviour ?

     Sathya
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