Justin Napolitano

A simple shell script to resolve and export the current WAN IP address of a home network by querying multiple public DNS resolvers. The script logs results and updates an environment file with the resolved IP.

Features

Resolves a predefined hostname (jayburd.duckdns.org) via multiple public DNS resolvers (Cloudflare, Google, Quad9).
Falls back to system DNS resolution methods if public resolvers fail.
Exports the resolved IP address to an environment file (~/.home_ip.env).
Maintains a log of resolution attempts and outcomes.

Tech Stack

Shell scripting (Bash)
Uses standard Unix utilities: dig, host, getent, ping, awk

Getting Started

Prerequisites

Bash shell
dig utility (usually from bind-utils or dnsutils package)
Optional: host, getent, ping for fallback DNS resolution

Installation

Clone the repository:

git clone https://github.com/justin-napolitano/pullhomeip.git
cd pullhomeip

Make the script executable:

chmod +x pull_home_ip.sh

Usage

Run the script directly:

./pull_home_ip.sh

This will update the ~/.home_ip.env file with the current WAN IP and append logs to ~/.local/share/duckdns/pull_ip.log.

To load the IP into your shell environment:

source ~/.home_ip.env

Project Structure

pullhomeip/
└── pull_home_ip.sh   # Main script to resolve and export WAN IP

pull_home_ip.sh: Bash script that performs DNS resolution and logging.

Future Work / Roadmap

Parameterize the hostname instead of hardcoding jayburd.duckdns.org.
Add options to specify output environment file and log location.
Support IPv6 resolution.
Add unit tests or integration tests.
Provide Docker containerization for easier deployment.
Add cron job installation instructions or automation.

This project assumes the user wants a lightweight, reliable way to update their WAN IP environment variable for scripts or other automation that depends on the current external IP address.