propellor

property-based host configuration management in haskell.

Propellor ensures that the system it's run in satisfies a list of properties, taking action as necessary when a property is not yet met.

It is configured using haskell.

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

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. See components for details.

Properties are defined using Haskell in the file ~/.propellor/config.hs. 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, 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). apt-get install propellor or cabal install propellor or cabal unpack propellor; cd propellor-version; stack install
2. Run propellor --init ; this will set up a ~/.propellor/ git repository for you.
3. Edit ~/.propellor/config.hs, and add a host you want to manage. You can start by not adding any properties, or only a few.
4. Run: propellor --spin $HOST
5. Now you have a simple propellor deployment to a host. Continue editing ~/.propellor/config.hs to further configure the host, add more hosts etc, and re-run propellor --spin $HOST after each change.
6. Once you have a lot of hosts, and running propellor --spin HOST for each host becomes tiresome, you can automate that.
7. Write some neat new properties and send patches!

(Want to get your feet wet with propellor before plunging in? try this)