system administration

Puppetlinter dot com

A while back I created the website. It allows you to quickly and easily validate Puppet code against several different versions of Puppet. Today Josh had an idea. Why not a bookmarklet to easily validate Puppet code from a website. Why not?

Validate Puppet Code

  1. drag the bookmarklet link above to your bookmarks menu.
  2. Highlight some code on a webpage.
  3. Click your bookmarklet link.

Docker Docker Docker

Docker docker docker

One thing we do a lot of at Puppet Labs is release product. And every time we make a major product release, I have to go through and update our training material. I validate all the exercises and examples and code snippets. And when we make UI refreshes I have to take all new screenshots. That doesn't sound like much--it's just taking some pictures, right? Well, yeah... but what am I going to take pictures of? Just firing up a master and screenshotting away isn't very interesting or informing.

Oh, the fun things we can write!

boring text

So now we've used Puppet to manage a file on our computer. The /etc/motd file is now owned by root and has a fun little sentence in it. We can write all we want out to that file. But sooner or later, we're going to want to put something a little more interesting. Perhaps we'll want the hostname or operating system installed?

We'll take a little side trip first, though, and learn about $variables.

Puppet Zero

Puppet Zero

Configuration management with tools like Puppet can make your life a lot easier. It can make configuring newly provisioned servers more repeatable and reliable and it can make disaster recovery nearly trivial. Learning to use the tool isn't trivial by any means, though. There are 200 configurable options, give or take depending on the version you're running, and the number of things you can do with it is nearly infinite.

So what is this Puppet thing anyway?

Puppet Zero

So you keep hearing about this Puppet thing and how it's going to solve all of your DevOpsy configuration management problems. But what is it? How do you write a Puppet script? Well, as it turns out, the key concept is unlearning the habit of thinking about scripts. But all in good time. We'll get there. First, let's write some code.

Let's start out with something easy. You all know what the /etc/motd file is. It's the message of the day file that's dumped to your screen every time you log in.