Linux bash script – mail when threshold increase of disk

Hi there!
Today at work I needed to use a script to send me a mail notification when the the disk was about to get full during an installation.

One could argue that I should’ve used some sort of bigger system like Nagios to get these messages, but in this scenario, this script that I wrote suits me better.

The script looks like this:

CURRENT=$(df / | grep / | awk ‘{ print $5}’ | sed ‘s/%//g’)

if [ “$CURRENT” -gt “$THRESHOLD” ] ; then
mail -s ‘Disk Space Alert’ << EOF
Your root partition remaining free space is critically low. Used: $CURRENT%

Where the “Current” variable looks at the disk and where “Threshold” is the percentage of disk being used.

For example in this script, when the disk is (-gt ‘greater than’) over the defined threshold it should use the command “mail” to send me a message of the current state.

Configure it the way you want it and change the email to your own.
Save it as then add it to crontab.

Easy huh? yeah.