This is my lean and effective way to monitor your public IP address with Python, specifically Python3. The script – code and GitHub link below – runs on a continuous loop, which I covered in a previous post: here.

NOTE: this code is reliant on the dig system command – so this essentially only work on a unix based system. I was running this on a Debian install.

import os
import subprocess
import re
import time

print("start monitor vpn monitor check")

expected_IP: "0.0.0.0" # ENTER YOUR EXPECTED PUBLIC IPv4 ADDRESS HERE

current_IP: subprocess.check_output("dig +short myip.opendns.com @resolver1.opendns.com", shell=True)

try:
    while True:
        if expected_IP in str(current_IP):
            print("IPs Match - Things are normal")
        else:
            print("Current IP: " + str(current_IP) + "\nIP NOT AS EXPECTED!")
            #Code to complete actions called here
        time.sleep(60) # Change this timer to reduce/increase time between checks (seconds)
except KeyboardInterrupt:
    print("\nHard Exit Initiated. Goodbye!")

https://github.com/Tombo1001/PyIPmonitor

Alternative uses

There are a number of use cases for this code, mine was checking if my computer is still connected to a VPN. Monitor my public IP address meant that I could tell if the VPN had disconnected.

Checking my IP matches my VPN endpoint IP The only thing that was changed here from the current repository code is the print statements – the output just matches the context of the code’s use.

More python snippets

Here are some links to some of my other python code samples: