Get Server Notification on Telegram App

Bash Script to send report to telegram if high resource usage is found in the server.

Here is a bash script that can monitor server load and memory usage at regular intervals. It has been tested on Centos 7. The telegram API is used to send attachment instead of just text message. This is because sending text has character limit. Resource usage statistics can be sent in attachment instead of plain message.

#!/bin/bash
#This script monitors server load and memory usage for every 10 seconds and sends notification to telegram in case of high usage.

#Include telegram chat id and bot token ID here
chat_id="123456789"
token="112233445:AABbcd1FfggHHi22jkLmmn0PPQQRstu"

#Temporary files to store data
resource_usage_info=/tmp/resource_usage_info.txt
msg_caption=/tmp/telegram_msg_caption.txt

#Set threshold levels for memory usage and load here. If the usage exceeds these values, the notification will be sent.
mem_threshold=90 #Should be interger. This is in percentage
load_threshold=$(nproc) #Should be integer. Usually total number of cores.

#Telegram API to send notificaiton.
function telegram_send
{
curl -s -F chat_id=$chat_id -F document=@$resource_usage_info -F caption="$caption" https://api.telegram.org/bot$token/sendDocument > /dev/null 2&>1
}

#Monitoring Load on the server
while :
do
    min_load=$(cat /proc/loadavg | cut -d . -f1)
    if [ $min_load -ge $load_threshold ]
        then
        echo -e "High CPU usage detected on $(hostname)\n$(uptime)" > $msg_caption
        echo -e "CPU usage report from $(hostname)\nServer Time : $(date +"%d%b%Y %T")\n\n\$uptime\n$(uptime)\n\n%CPU %MEM USER\tCMD" >         $resource_usage_info
        ps -eo pcpu,pmem,user,cmd | sed '1d' | sort -nr >> $resource_usage_info 
        caption=$(<$msg_caption)
        telegram_send
        rm -f $resource_usage_info
        rm -f $msg_caption
        sleep 900 #stop executing script for 15 minutes
    fi
    sleep 10

#Monitoring Memory usage on the server
    mem=$(free -m)
    mem_usage=$(echo "$mem" | awk 'NR==2{printf "%i\n", ($3*100/$2)}')
    if [ $mem_usage -gt $mem_threshold ]
    then
        echo -e "High Memory usage detected on $(hostname)\n$(echo $mem_usage% memory usage)" > $msg_caption
        echo -e "Memory consumption Report from $(hostname)\nServer Time : $(date +"%d%b%Y %T")\n\n\$free -m output\n$mem\n\n%MEM %CPU USER\tCMD" > $resource_usage_info
        ps -eo pmem,pcpu,user,cmd | sed '1d' | sort -nr >> $resource_usage_info
        caption=$(<$msg_caption)
        telegram_send
        rm -f $resource_usage_info
        rm -f $msg_caption
        sleep 900 #stop executing script for 15 minutes
    fi 
    sleep 10
done