Every once in a while I come across a new tool. After a few weeks of using it I think: Darn, how was I ever able to do a good job without it? Today I’d like to introduce you to such a tool: Puppet

<insert witty remark about grown men and women playing with puppets here>

Puppet is a
configuration management framework. A what? You tell Puppet what needs to be installed and configured on your servers and Puppet does that for you. Every few minutes it can ensure that everything is still in place and running properly, and if something is broken maybe even fix it.
Puppet is very modular. You can reuse the same instructions on as many servers as you want. Adding a new server? Add a couple of lines to your manifest. Done.
Back at my previous employer local.ch I was able to run about 100 hosts more or less single-handedly and keep the dark rings under my eyes to a minimum. Puppet is like having a room full of extra sysadmins that constantly log into your servers and check if everything is still in place. They never sleep, the don’t make mistakes and they never browse Facebook. ;-) Or in other words, Puppet puts the fun back into being a Sysadmin, because it takes away the repetitive chores.

If you are already sold, you can start your journey here.

If not let me walk you trough a simple example. Installing and configuring a simple webserver.

Let puppet install the webserver for you:

package {
    "apache2":
        ensure => installed;
    }
}

Let puppet ensure the webserver is running:

service {
    "apache2":
        ensure => running,
        require => Package["apache2"];
}

file {
    "/etc/apache/conf/httpd.conf":
        ensure => present,
        owner => root,
        group => root,
        mode => 664,
        content => template("modules/apache/httpd.conf.erb"),
        require => Package["apache2"],
        notify => Service["apache2"];
}