Script for monitoring disk space in Linux

The script below is designed to monitor disk space usage on a specified server partition. Configurable parameters include the maximum allowable percentage of disk space usage (MAX), the e-mail address to receive alerts (EMAIL) and the target partition (PARTITION).

The script uses the df command to collect disk usage information and sends email alerts if the current usage exceeds the specified threshold

#!/bin/bash
# Script: ./df_guard.sh [config_file]

# Set the maximum allowed disk space usage percentage
MAX=90

# Set the email address to receive alerts
EMAIL=user@example.com

# Set the partition to monitor (change accordingly, e.g., /dev/sda1)
PARTITION=/dev/sda1

# Get the current disk usage percentage and related information
USAGE_INFO=$(df -h "$PARTITION" | awk 'NR==2 {print $5, $1, $2, $3, $4}' | tr '\n' ' ')
USAGE=$(echo "$USAGE_INFO" | awk '{print int($1)}') # Remove the percentage sign

if [ "$USAGE" -gt "$MAX" ]; then
# Send an email alert with detailed disk usage information
echo -e "Warning: Disk space usage on $PARTITION is $USAGE%.\n\nDisk Usage Information:\n$USAGE_INFO" | \
mail -s "Disk Space Alert on $HOSTNAME" "$EMAIL"
fi

Installation

sudo install -m 0755 df_guard.sh /usr/local/bin/df_guard.sh

Make the script executable:

sudo chmod +x /usr/local/bin/df_guard.sh

Launch examples

• Every 15 minutes.

In crontab (root)

*/15 * * * * * /usr/local/bin/df_guard.sh