Bash - Boot script - Run script on reboot (auto restart) or on a schedule

Edit to /etc/crontab file.

sudo vim /etc/crontab

Add @reboot followed by the user to run and the script.

@reboot ubuntu /home/ubuntu/my_script.sh

You can also add the above line into the crontab directory /etc/cron.d/ (do not use filename extension)

The following runs a script at the top of every hour.

sudo bash -c "echo '0 * * * * ubuntu /home/ubuntu/my_script.sh' > /etc/cron.d/myScript";