Bash Script to Monitor CPU, Memory and Swap usage on Multiple Linux System With eMail Alert

You have a small infrastructure and want to check multiple system performance simultaneously for some reason.

This script will help you to create a report for you.

You can use this script to generate a CPU, memory and swap usage for a multiple Linux system.

Three shell scripts are added in this tutorial to generate a report.

Each bash script has written with unique features and choose the one you need.

Also, you can modify this script based on your needs.

Method-1 : Shell Script to Check CPU, Memory and Swap usage on Multiple Linux System

This script allows you to check CPU, memory and swap usage on multiple Linux system from the terminal.

# vi /opt/scripts/cpu-memory-swap.sh

#!/bin/bash
echo "-------------------------------------------"
echo "Server_Name   CPU(%)   Memory(%)   Swap(%)"
echo "-------------------------------------------"
for server in `more /opt/scripts/server-list.txt`
do
scpu=$(ssh $server cat /proc/stat | awk '/cpu/{printf("%.2f%\n"), ($2+$4)*100/($2+$4+$5)}' |  awk '{print $0}' | head -1)
smem=$(ssh $server free | awk '/Mem/{printf("%.2f%"), $3/$2*100}')
sswap=$(ssh $server free | awk '/Swap/{printf("%.2f%"), $3/$2*100}')
echo "$server   $scpu   $smem   $sswap"
done | column -t
echo "-------------------------------------------"

Set an executable Linux file permission to “cpu-memory-swap.sh” file.

# chmod +x /opt/scripts/cpu-memory-swap.sh

When you run the script you will get a result like the one below.

# sh cpu-mem-black.sh

---------------------------------------------------
Server_Name             CPU(%) Memory(%)   Swap(%)
---------------------------------------------------
CentOS7.2daygeek.com    0.04%  12.77%      0.00%
Ubuntu18.2daygeek.com   0.29%  28.43%      0.00%
---------------------------------------------------

Method-2 : Shell Script to Monitor CPU, Memory and Swap usage on Multiple Linux System with eMail alert

This Bash script collects and sends a mail with a CPU, Memory and Swap usage for a given Linux system at a given interval in a text file.

# vi /opt/scripts/cpu-memory-swap-1.sh

#!/bin/bash
if which mailx > /dev/null
then
echo "mailx package is exist"
elif (( $(cat /etc/*-release | grep "Red Hat" | wc -l) > 0 ))
then
yum install mailx -y > /dev/null 
else
apt install mailutils -y > /dev/null
fi
echo "-------------------------------------------" >> /tmp/cpu-mem-swap.txt
echo "Server_Name   CPU(%)   Memory(%)   Swap(%)" >> /tmp/cpu-mem-swap.txt
echo "-------------------------------------------" >> /tmp/cpu-mem-swap.txt
for server in `more /opt/scripts/server-list.txt`
do
scpu=$(ssh $server cat /proc/stat | awk '/cpu/{printf("%.2f%\n"), ($2+$4)*100/($2+$4+$5)}' |  awk '{print $0}' | head -1)
smem=$(ssh $server free | awk '/Mem/{printf("%.2f%"), $3/$2*100}')
sswap=$(ssh $server free | awk '/Swap/{printf("%.2f%"), $3/$2*100}')
echo "$server   $scpu   $smem   $sswap" >> /tmp/cpu-mem-swap.txt
done | column -t
echo "-------------------------------------------" >> /tmp/cpu-mem-swap.txt
echo "CPU and Memory Report for `date +"%B %Y"`" | mailx -s "CPU and Memory Report on `date`" -a /tmp/cpu-mem-swap.txt [email protected]
rm /tmp/cpu-mem-swap.txt

Set an executable Linux file permission to “cpu-memory-swap-1.sh” file.

# chmod +x /opt/scripts/cpu-memory-swap-1.sh

Finally add a cronjob to automate this. It runs every 2 hours.

# crontab -e
0 */2 * * * /bin/bash /opt/scripts/cpu-memory-swap-1.sh

Note: You will receive an email alert every 2 hours.

Method-3 : Shell Script to Monitor CPU, Memory and Swap usage on Multiple Linux System with eMail alert

This Bash script collects and sends a mail with a CPU, Memory and Swap usage for a given Linux system at a given interval in a excel file.

# vi /opt/scripts/cpu-memory-swap-2.sh

#!/bin/bash
if which mailx > /dev/null
then
echo "mailx package is exist"
elif (( $(cat /etc/*-release | grep "Red Hat" | wc -l) > 0 ))
then
yum install mailx -y > /dev/null 
else
apt install mailutils -y > /dev/null
fi
echo "Server_Name, CPU, Memory, Swap" > /tmp/cpu-mem-swap.csv
for server in `more /opt/scripts/server-list.txt`
do
scpu=$(ssh $server cat /proc/stat | awk '/cpu/{printf("%.2f%\n"), ($2+$4)*100/($2+$4+$5)}' |  awk '{print $0}' | head -1)
smem=$(ssh $server free | awk '/Mem/{printf("%.2f%"), $3/$2*100}')
sswap=$(ssh $server free | awk '/Swap/{printf("%.2f%"), $3/$2*100}')
echo "$server, $scpu, $smem, $sswap" >> /tmp/cpu-mem-swap.csv
done
echo "CPU and Memory Report for `date +"%B %Y"`" | mailx -s "CPU and Memory Report on `date`" -a /tmp/cpu-mem-swap.csv  [email protected]
rm /tmp/cpu-mem-swap.csv

Set an executable Linux file permission to “cpu-memory-swap-2.sh” file.

# chmod +x /opt/scripts/cpu-memory-swap-2.sh

Finally add a cronjob to automate this. It will run everyday at 8’o clock.

# crontab -e

0 8 * * * /bin/bash /opt/scripts/cpu-memory-swap-2.sh

Note: You will be getting an email alert everyday at 8 o’clock.

You will receive a output like the one below by mail.