Error starting flowable services

Flowable Engine
1

Hi,

We have configured separate webapps flowable-rest and flowable-modeler to run on same H2 database as services. Once in a blue moon, we hit upon following error while restarting the flowable-modeler service. flowable-rest works fine.

[2021-01-12T02:47:11.996-0800] [main] [] [] [] [] [l.e.j.JdbcExecutor] [INFO ] - SELECT LOCKED FROM PUBLIC.ACT_DE_DATABASECHANGELOGLOCK WHERE ID=1
[2021-01-12T02:47:11.998-0800] [main] [] [] [] [] [l.l.StandardLockService] [INFO ] - Waiting for changelog lock…

Can somebody please help me understand why this happens and what is the best fix for such a scenario?

Also, does it impact the data in any way?

TIA,
Deepanshu

2

Running H2 in production is not advised. The failure for getting the lock is because two nodes try to lock the same row on bootup (so this is not related to runtime data).

3

Thanks Joram,

So removing the lock using SQL should not do any harm to get the service back up. Is this statement correct?

In the meantime, I will start working towards changing the database.

Thanks,
Deepanshu