Objective: Create a
cron job for your backup script.
Now that you have a simple backup script, you want to run it periodically to ensure that your data is copied to another part of your VPS to keep it safe from accidental deletion.
You will use the
crontab application to install, remove, or edit
Edit the cron jobs.
Choose a time to run the script.
You should perform the backup when the system has low usage, such as a when most of your users are sleeping.
Pick a time between 02:00 to 05:00.
Build your cron job. This example runs at 03:00 daily.
0 3 * * * <command-to-execute>
List the cron jobs to verify that they installed correctly.
It is not easy to test cron jobs that run infrequently. You need to know
(1) Did it run and (2) did it run correctly.
You can run a cron job manually using Webmin:
Webmin -> System -> Scheduled Cron Jobs
The output will display to the browser.
Another method is to log the output data to a file instead of to the screen. You can use this information to determine if it ran and if it produced expected data.
You can configure a command to send standard output (stdout) results to a file instead of the the screen using
command > /path/to/output.txt
# shell commands ls -lh > dir-listing.txt ./backup-docker.sh > /tmp/output.txt # from a cron job 0 3 * * * bash /root/backup-user-data.sh > /var/user-backups/backup-log.txt