Periodically check home IP address and update on server to allow port 53

script.sh

#!/bin/bash
# Setup Reference: https://blog.sbstp.ca/vps-pihole/
# Run this script as CRON Job in your laptop or any device.
# Author - mcnaveen<me@mcnaveen.com>

ip=$(curl -s https://api.ipify.org | grep -oE '[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+')
ip_file="ip_address.txt"
vps_ip="YOUR_VPS_IP_ADDRESS"

if [[ -f $ip_file ]]; then
    stored_ip=$(cat $ip_file)
fi

if [[ $ip != $stored_ip ]]; then
   ssh root@$vps_ip "sudo ufw delete allow from $stored_ip to any port 53 && sudo ufw allow from $ip to any port 53"
fi

echo $ip > $ip_file