www.nico.schottelius.org/software/cdist.mdwn

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[[!toc  levels=2]]

## Introduction

cdist configures your system and is similar to
other configuration management systems like
[cfengine](http://www.cfengine.org/),
[bcfg2](http://trac.mcs.anl.gov/projects/bcfg2),
[chef](http://wiki.opscode.com/display/chef/)
and [puppet](http://www.puppetlabs.com/), but
it ticks differently:

 * cdist sticks completly to the KISS (keep it simple and stupid) paradigma
  * cdist's core is very small (< 1k lines of code)
  * There is only one type to extend cdist called ***type***.
  * One main development target: ***It must be incredible easy to add new types.***
 * cdist is UNIX
  * It reuses existing tools like cat, find, mv, ...
  * cdist's documentation is bundled as manpages
 * cdist is written in POSIX shell
  * No special requirements like high level interpreters needed on server or target

### Documentation

The cdist documentation is included as manpages in the distribution.
You can [browse the documentation for the latest version online](man) as well.

### Architecture

 * Push mode (server pushes configuration)
 * User defines configuration in shell scripts (called ***manifests***)
 * Generates internal configuration (cconfig style)
 * Uses ***types*** to generate code be executed on the target
 * And finally executes the code on the target / applies the configuration

### Features

Stuff that should probably be included in every configuration management,
but is not. Or: Why I began to write cdist:

 * Speed
 * Elegant code
 * Clean design
 * Good documentation (man pages)
 * Meaningful error messages
 * The no surprise factor
 * Consistency in behaviour, naming and documentation
 * Easy integration into bare metal installations
 * Simple and well-known DSL: posix shell
 * It must be very easy to extend and debug cdist
 * Focus on reuse of existing functionality (like sh, ssh, find, rm, ...)
 * Easy upgrade: ***There is no need to update cdist on target hosts!***
  * cdist only needs to be update on the master server

### OS support

cdist was tested or is know to run on at least

 * [Archlinux](http://www.archlinux.org/)
 * [Debian](http://www.debian.org/)
 * [Gentoo](http://www.gentoo.org/)
 * [Mac OS X](http://www.apple.com/macosx/)
 * [Redhat](http://www.redhat.com/)
 * [Ubuntu](http://www.ubuntu.com/)


## Requirements

### Server

 * A posix like shell
 * SSH-Client

### Client ("target host")

 * A posix like shell
 * SSH-Server


## Getting cdist

You can clone cdist from git, which gives you the advantage of having
a version control in place for development of your own stuff as well.

### Installation

To install cdist, execute the following commands:

    git clone git://git.schottelius.org/cdist
    cd cdist
    export PATH=$PATH:$(pwd -P)/bin

    # If you want the manpages (requires asciidoc to be installed)
    make man
    export MANPATH=$MANPATH:$(pwd -P)/doc/man


Afterwards you can run ***cdist-quickstart*** to get an impression on
how to use cdist.

### Available versions

There are at least the following branches available:

 * master: the development branch
 * 1.3: Support for local and remote code execution (current stable)

Old versions:

 * 1.0: First official release
 * 1.1: __file to __file, __directory, __link migration
 * 1.2: Dependencies supported

Other branches may be available for features or bugfixes, but they
may vanish at any point. To select a specific branch use

    # Generic code
    git checkout -b <name> origin/<name>
    
    # Stay on a specific version
    git checkout -b 1.3 origin/1.3

### Mirrors

 * git://github.com/telmich/cdist.git ([github](https://github.com/telmich/cdist))
 * git://git.sans.ethz.ch/cdist ([sans](http://git.sans.ethz.ch/?p=cdist;a=summary))

## Update

To upgrade cdist in the current branch use

    git pull

    # Also update the manpages
    make man
    export MANPATH=$MANPATH:$(pwd -P)/doc/man

If you stay on a version branche (i.e. 1.0, 1.1., ...), nothing should break.
The master branch on the other hand is the development branch and may not be
working, break your setup or eat the tree in your garden.

### Upgrading from 1.2 to 1.3

Rename **gencode** of every type to **gencode-remote**.

### Upgrading from 1.1 to 1.2

No incompatiblities.

### Upgrading from 1.0 to 1.1

In 1.1 the type **\_\_file** was split into **\_\_directory**, **\_\_file** and
**\_\_link**. The parameter **--type** was removed from **\_\_file**. Thus you
need to replace **\_\_file** calls in your manifests:

 * Remove --type from all \_\_file calls
 * If type was symlink, use \_\_link and --type symbolic
 * If type was directory, use \_\_directory


## Support

### IRC

You can join the development ***IRC channel***
[#cLinux on irc.freenode.org](irc://irc.freenode.org/#cLinux).

### Mailing list

Bug reports, questions, patches, etc. should be send to the
[cdist mailing list](http://l.schottelius.org/mailman/listinfo/cdist).

## Used by

If you're using cdist, feel free to send a report to the mailing list.
Interesting information are for instance

 * Which services do you manage?
 * How many machines do you manage?
 * What are the pros/cons you see in cdist?
 * General comments/critics

### Nico Schottelius, Systems Group ETH Zurich

Yes, I'm actually eating my own dogfood and currently managing

 * [plone](http://plone.org/) (cms)
 * [moinmoin](http://moinmo.in/) (wiki)
 * [apache](http://httpd.apache.org/) (webserver)
 * [kerberos (mit)](http://web.mit.edu/kerberos/) (authentication)
 * [ircd-hybrid](http://www.ircd-hybrid.org/) (chat)
 * [stunnel](http://stunnel.mirt.net/) (SSL tunnel)
 * [mercurial-server](http://www.lshift.net/mercurial-server.html) (version control)
 * [xfce](http://www.xfce.org/) (lightweight desktop environment)
 * [slim](http://slim.berlios.de/) (graphical login manager for X11)

with cdist on a total of **5** production machines of the
[Systems Group](http://www.systems.ethz.ch) at the
[ETH Zurich](http://www.ethz.ch).

### Steven Armstrong, CBRG ETH Zurich

The CBRG is managing most of their compute clusters with cdist.