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Tue Feb 14 09:17:33 2012 testuser/1XX.1XX.1XX.X:1042 SIGTERM[soft,remote-exit] received, client-instance exiting
shows that the client "choose" to exit - most likely due to a 'keepalive N M' setting on the server, which is pushed out to the client. Track down the client log file to see why it stopped.