Dmitriy Loginov

#!/bin/bash

HOSTS="google.com 8.8.4.4"

SUBJECT="Host Down"

ping_attempts=1
down_hosts=/stuff/scritp/down_hosts.txt

for myHost in $HOSTS
do
        count=$(ping -c $ping_attempts $myHost | awk -F, '/received/{print $2*1}')

        if [ $count -eq 0 ]; then
                if  [ $(grep -c "$myHost" "$down_hosts") -eq 0 ]; then
                        /usr/bin/curl -s -X POST https://api.telegram.org/botTOKEN/sendMessage -d chat_id=123 -d text="$myHost ping FAILED at $(date)" > /dev/null 2>&1
                       echo "$myHost" >> $down_hosts
                fi
        else
                if  [ $(grep -c "$myHost" "$down_hosts") -eq 1 ]; then
                         /usr/bin/curl -s -X POST https://api.telegram.org/botTOKEN/sendMessage -d chat_id=123 -d text="$myHost ping OK at $(date)" > /dev/null 2>&1
                        sed -i "/$myHost/d" "$down_hosts"
                fi
        fi
done