2287030 - IQ server goes down with error "Unable to synchronize due to external event"

• IQ server goes down randomly with messages similar to these in .srvlog

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I. 02/17 14:47:45. Trying to start SharedMemory link ...
I. 02/17 14:47:45. SharedMemory link started successfully
I. 02/17 14:47:45. Trying to start TCPIP link ...
I. 02/17 14:47:45. Starting on port 2640
I. 02/17 14:47:50. TCPIP link started successfully
I. 02/17 14:47:50. Now accepting requests
E. 02/17 14:50:02. Unable to synchronize due to external event - server shutting down
I. 02/17 14:50:02. Database server shutdown due to HUP signal
I. 02/17 14:50:02. Starting checkpoint of "LP1" (LP1.db) at Wed Feb 17 2016 14:50
I. 02/17 14:50:02. Finished checkpoint of "LP1" (LP1.db) at Wed Feb 17 2016 14:50
I. 02/17 14:50:02. TCPIP listener on IP address 0.0.0.0:2640 is exiting
I. 02/17 14:50:03. Database server stopped at Wed Feb 17 2016 14:50
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• .iqmsg shows that the database shutdown is not abrupt. Shutdown is clean.

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I. 02/17 14:50:00. 0000000076 Collation CESU8BIN, Case Respect, Blank Padding On, Comparisons are Conditioned
I. 02/17 14:50:00. 0000000076 Txn 809785 0 0
I. 02/17 14:50:00. 0000000076 Cmt 809786
I. 02/17 14:50:00. 0000000076 PostCmt 0
I. 02/17 14:50:02. 0000000081 Chk
I. 02/17 14:50:02. 0000000081 ChkDone [NumTxnCP: 0]
I. 02/17 14:50:02. 0000000081 PostChk
I. 02/17 14:50:02. 0000000000 CloseDatabase
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• There is no connection OR CRON job which is shutting the database down on purpose.
  There are no user events created in IQ database. There is no xp_cmdshell() execution from within IQ.
  DBA observes that any unrelated and simple CRON job run is bringing down IQ database.

• SAP IQ 16 SP 10+
• Redhat Linux 7.2

KBA , BC-SYB-IQ , Sybase IQ , Problem