Miroslav Novak created ARTEMIS-679:
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             Summary: Activate most up to date server from 
master-slave(live-backup) pair
                 Key: ARTEMIS-679
                 URL: https://issues.apache.org/jira/browse/ARTEMIS-679
             Project: ActiveMQ Artemis
          Issue Type: New Feature
          Components: Broker
    Affects Versions: 1.3.0
            Reporter: Miroslav Novak


if there are 2 live/backup pairs with replicated journal in colocated topology 
Artemis1(L1/B2) <-> Artemis2(L2/B1) then there is no easy way to start them if 
they're all shutdown.

Problem is that there is no way how to start the servers with most up-to-date 
journal. If administrator shutdown servers in sequence Artemis1 and then 
Artemis 2. Then Artemis 2 has the most up-to-date journals because backup B1 on 
server2 activated.
Then If administrator decides to start Artemis2 then live L2 activates and 
backup B1 waits for live L1 in Artemis 1 to start. But once L1 starts then L1 
replicates its own "old" journal to B1.

So L1 started with bad old journal. I would suggest that L1 and B1 compares 
theirs journals and figure out which one is more up-to-date. Then server with 
more up-to-date journal activates.

In scenario described above it would be backup B1 which will activate first. 
Live L1 will synchronize its own journal from B1 and then failback happens. 



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