Shell script for getting an Alert Mail if the Disk Usage reaches 90% of space Linux

Prerequisites:

Any one of the below mail utility must be present on the linux server

1. sendmail

2. mail

3. mutt

4. ssmtp

5. telnet

1. Below script will send an alert mail if the disk usage space of a directory in linux server reaches 90%

In this script I used "mail" utility for sending alert mails

ADMIN="lravikumarvsp@gmail.com"

ALERT=90

message=$(df -h | awk -v ALERT="$ALERT" '

    NR == 1 {next}

    $1 == "abc:/xyz/pqr" {next}

    $1 == "tmpfs" {next}

    $1 == "/dev/cdrom" {next}

    1 {sub(/%/,"",$5)}

    $5 >= ALERT {printf "%s is almost full: %d%%\n", $1, $5}

')

if [ -n "$message" ]; then

  echo "$message" | mail -s "Alert: Almost out of disk space" "$ADMIN"

fi

2. Below script will send an alert mail if the disk usage space of the root partition in linux server exceeds 90%

#!/bin/bash

CURRENT=$(df / | grep / | awk '{ print $4}' | sed 's/%//g')

THRESHOLD=90

if [ "$CURRENT" -gt "$THRESHOLD" ] ; then

    mail -s 'Disk Space Alert' lravikumarvsp@gmail.com << EOF

Your root partition remaining free space is critically low. Used: $CURRENT%

EOF

fi