Network connectivity monitoring script: Alert failed pings only (Python script)
Last updated on February 8th, 2025Monitoring network connectivity can be crucial when investigating an intermittent issue. This article aims to share a simple Python script to monitor network connectivity using the ping command on either Windows or Linux operating systems.
The script continuously pings a specified host and logs any connectivity failures, all while maintaining compatibility across different operating systems.
Prerequisites
Before diving into the script, ensure you have the following:
- Python installed on your system (Python 3.6 or later is recommended)
- Basic knowledge of programming
The script
Here’s the complete Python script:
# This script pings a host on a fixed frequency (defaulted to 5 seconds) and only reports if a ping fails. This is useful for monitoring the stability of a connection without needing to scroll through successful pings for failed ones.
# --------------
# Configuration
# --------------
# - Target host: Change the first parameter on the final line if you are monitoring a specific host. This is initially set to Google's DNS service at 8.8.8.8 to monitor Internet connectivity of the device running this script.
# - Frequency: Change the second parameter on the final line if you require a different frequency. This is initially set to 5 seconds between pings.
import subprocess
import time
from datetime import datetime
import platform
def attempt_ping(host):
# Check the operating system (Windows ping uses -n to set ping count, Linux uses -c)
param = '-n' if platform.system().lower() == 'windows' else '-c'
# Send one ping to the host
# stdout and stderr values of subprocess.DEVNULL hide the ping command output so this script handles all output
result = subprocess.run(['ping', param, '1', host], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
return result.returncode
def monitor_host(host, interval=5):
while True:
if attempt_ping(host) != 0:
timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
print(f"{timestamp} - Failed to reach {host}")
time.sleep(interval)
if __name__ == "__main__":
monitor_host("8.8.8.8", 5)Explanation
Let’s break down the script step-by-step:
- Importing modules: We start by importing necessary modules:
subprocessfor running external commands (in this case,ping)timefor adding delays between pingsdatetimefor timestamping outputsplatformfor detecting the operating system (needed to use the appropriatepingparameters)
- Ping function: The
attempt_pingfunction sends a single ping to the specified host. It first checks the operating system usingplatform.system(). If the OS is Windows, it uses the-nparameter; otherwise, it uses-c(common to Unix-like systems including Linux). Thepingcommand’s output is suppressed by redirectingstdoutandstderrtosubprocess.DEVNULL. - Monitor function: The
monitor_hostfunction continuously pings the host at specified intervals (default is 5 seconds). If a ping fails, it logs the timestamp and the failure message. The script runs in an infinite loop, usingtime.sleep(interval)to wait between pings. - Main function: The script starts execution from the
if __name__ == "__main__":block, calling themonitor_hostfunction with the target host “8.8.8.8” (Google’s public DNS server).
Usage
- Save the script as
monitor_network.py. - Open a terminal or command prompt and navigate to the directory where the script is saved.
- Run the script with the command:
python monitor_network.py.
The script will start pinging the specified host and print messages if it fails to reach the host, providing a timestamp for each failure. Please note, there is no output if the ping is successful, this deliberate to avoid “noise” in the output when monitoring. If you want to see successful pings too, you can adjust the script or simply call the ping command directly.
Happy monitoring!