#!/bin/bash

This script is used to monitor the server resources, including CPU, Memory and Disk, and then send alert emails.

Monitor the server resources

resource_usage=top -n 1 | grep -E 'Cpu|Mem|/dev'

Get the server info

host_name=hostname host_ip=hostname -i

Define the alert threshold

cpu_usage_threshold=80 mem_usage_threshold=80 disk_usage_threshold=80

Get the current usage

cpu_usage=echo $resource_usage | awk '{print $2}' | sed -e 's/[^0-9]//g' mem_usage=echo $resource_usage | awk '{print $4}' | sed -e 's/[^0-9]//g' disk_usage=echo $resource_usage | awk '{print $7}' | sed -e 's/[^0-9]//g'

Check the usage

if [ $cpu_usage -gt $cpu_usage_threshold ]; then echo 'CPU usage has exceeded the threshold of $cpu_usage_threshold%, the current usage is $cpu_usage%.' | mail -s 'Server Resource Alert: $host_name($host_ip)' admin@example.com fi

if [ $mem_usage -gt $mem_usage_threshold ]; then echo 'Memory usage has exceeded the threshold of $mem_usage_threshold%, the current usage is $mem_usage%.' | mail -s 'Server Resource Alert: $host_name($host_ip)' admin@example.com fi

if [ $disk_usage -gt $disk_usage_threshold ]; then echo 'Disk usage has exceeded the threshold of $disk_usage_threshold%, the current usage is $disk_usage%.' | mail -s 'Server Resource Alert: $host_name($host_ip)' admin@example.com fi