cfghist

A tool for creating a configuration history of Linux systems.

Idea

As someone who frequently experiments with operating systems, I wanted a way to save the changes I make for easy reproduction or reference later. While tools like Ansible work very well for this use case, writing a complete playbook upfront can be very time-consuming in my opinion.

I was looking for something that would track commands and files, allowing me to save changes after testing or revert to a previous version if needed. I couldn't really find anything like that, so I created this simple tool. The inspiration came from the configuration command in Cisco iOS.

How it works?

This tool leverages the snapshot capabilities of ZFS although it can be used without it, purely as configuration manager.

• A snapshot is created before any changes are made.
• Then, user enters a bash shell, where every command is saved to a temporary configuration file. Non-essential commands like ls can be filtered out using Regex.
• The edit command creates copy of an edited file in configuration directory, allowing for tracking of changes made to files.
• Upon completion, the quit command prompts the user to either save changes, create a new snapshot, or rollback to the previous state.

Commands are saved to a configuration file, and changes to all files are tracked using Git. Currently, there is no script available for recreating the system from the configuration files, but I will create one if the need arises. For now, I primarily use this tool for documenting changes made to my systems and for automatic snapshots and rollbacks.

Dependencies

• bash
• coreutils
• grep
• sed