The following article describes the steps that need to be taken to debug ISPConfig 3 server scripts. This procedure applies to all ISPConfig 3 versions incl. ISPConfig 3.1 and ISPConfig 3.2.
Enable the debug Loglevel in ISPConfig
Login to the ISPConfig interface and set the log level to Debug under System > System > Server Config (see also chapter 4.9.2.2 of the ISPConfig 3 manual) for the affected server. After one or two minutes, there should be more detailed messages in ISPConfig's system log (Monitor > System State (All Servers) > Show System-Log).
Disable the server.sh cronjob
Go to the command line of the server on which the error happens (on multi-server systems, it is often the slave and not the master) and run (as root):
crontab -e
Comment out the server.sh cron job:
#* * * * * /usr/local/ispconfig/server/server.sh > /dev/null >> /var/log/ispconfig/cron.log
Run the server script manually to get detailed debug output
Then run the command:
/usr/local/ispconfig/server/server.sh
This will display any errors directly on the command line which should help you to fix the error. If you need help, post the debug output in the ISPConfig forum.
When you have fixed the error, please don't forget to uncomment the server.sh cron job again.