You just have to read the log.
Problem #1: You are not using PHP CLI as clearly explained in our documentation. You are using PHP FastCGI:
INFO |140731 03:07:17|PHP SAPI :cgi-fcgi
Problem #2: PHP FastCGI has a maximum execution time of 300 seconds (5 minutes)
INFO |140731 03:07:17|Max. exec. time :300
Problem #3: Your backup needs to run longer than that. How do we know? Start of backup:
DEBUG |140731 03:07:17|*** Batching successive steps (nesting level 1)
Last log entry before the backup dies:
DEBUG |140731 03:12:14|Closing SQL dump file.
The elapsed time logged was 297 seconds. Taking into account the time it takes PHP to load and start the application we are at 300 seconds give or take one second. This makes us further suspect that the CRON daemon itself has a CRON job maximum time limit of 5 minutes (300 seconds).
As Dale said, you need to check with your host to confirm that they are killing the CRON job and ask them to extend the time limit.
Nicholas K. Dionysopoulos
Lead Developer and Director
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