g2p / propellor

property-based host configuration management in haskell

Propellor is a configuration management system using Haskell and Git. Each system has a list of properties, which Propellor ensures are satisfied.

Propellor is configured via a git repository, which typically lives in ~/.propellor/ on your development machine. Propellor clones the repository to each host it manages, in a secure way. The git repository contains the full source code to Propellor, along with its config file.

Properties are defined using Haskell. Edit ~/.propellor/config.hs to get started. There is fairly complete API documentation, which includes many built-in Properties for dealing with Apt and Apache , Cron and Commands , Dns and Docker, etc.

There is no special language as used in puppet, chef, ansible, etc.. just the full power of Haskell. Hopefully that power can be put to good use in making declarative properties that are powerful, nicely idempotent, and easy to adapt to a system's special needs!

If using Haskell to configure Propellor seems intimidating, see configuration for the Haskell newbie.

quick start

1. Get propellor installed on your development machine (ie, laptop). cabal install propellor or apt-get install propellor
2. Run propellor for the first time. It will set up a ~/.propellor/ git repository for you.
3. If you don't have a gpg private key already, generate one: gpg --gen-key
4. Run: propellor --add-key $KEYID, which will make propellor trust your gpg key, and will sign your ~/.propellor repository using it.
5. Edit ~/.propellor/config.hs, and add a host you want to manage. You can start by not adding any properties, or only a few.
6. Run: propellor --spin $HOST
7. Now you have a simple propellor deployment, but it doesn't do much to the host yet, besides installing propellor.
   So, edit ~/.propellor/config.hs to configure the host, add some properties to it, and re-run step 6.
   Repeat until happy and move on to the next host. :)
8. Optionally, set up a centralized git repository so that multiple hosts can be updated with a simple git commit -S; git push
9. Write some neat new properties and send patches!