settings.php was empty

[alexander1974]

A while ago I tried to upgrade my largest forum from 2.015 to 2.016 but I got errors and stopped after several hours.

So I did not do quite a few small forums for fear that the small forums also went wrong.
Now this morning I wanted a forum that still had 2.015 but I got the error:

Connection Problems
Sorry, SMF was unable to connect to the database. This may be caused by the server being busy. Please try again later.
It turned out that settings.php only contained the default content as it comes with a new forum.
The .bak was also emptied on June 24 at 0:15 am.
But this forum has always worked well.
What could be causing these files to be erased?

Is this something SMF has done in an attempt to upgrade itself or has anyone hacked me?

[Arantor]

It's a known bug in SMF that causes it to happen sometimes.