To make it more detailed regarding your issue: In your first post you said that the site returned with "Error establishing a database connection". So this leads me to the check wether the database service is even running. So you've checked and it was not. Then i told you to check logs, as there was not a whole lot of information except that the service crashes directly after starting, i adviced you to enable debug logging, so we can see what exactly happens. We found the issue is the tc.log file. As the moving of the file solved the issue, this must mean that the file was corrupted and not readable by the service, which leads us to the question "why is it corrupted?". First assumption, i just couldn't write anymore data to it as the disk is full, which was correct.
