When your Ubuntu server needs to be rebooted, say after a kernel update, the file
/var/run/reboot-required is created.
You can check for that file to see if a reboot is needed and usually you’ll get a message upon logging into the server saying so.
Here’s how you can get an email when a reboot is needed saving you the time of manually checking.
Make sure the
mailutils package is installed.
You can accept all the default options:
sudo apt-get update && sudo apt-get install mailutils
Create the following file
#!/usr/bin/env bash if [ -f /var/run/reboot-required ]; then echo "A reboot is required following updates to server <hostname>" | mail -s "Reboot Required" <email-address> fi
<hostname> with whatever you call your server and
<email-address> that you want the email to go to.
Make sure the file is has the right ownership and permissions:
sudo chown root:root /etc/cron.daily/reboot-check sudo chmod 755 /etc/cron.daily/reboot-check
Once a day the script will check if a reboot is required and email you if it is. Be sure to check your spam folder.
You can move this file from
cron.daily to another directly such as
cron.weekly to change the frequency.