Ever since I started playing around with Unix ~13 years ago, I’ve been a fan of automating things. What started out as writing little (maybe pointless) shell scripts slowly but surely morphed into infrastructure automation today.
As for my, or maybe anyone’s, motivation to do these things, I see three main factors:
- I’m easily bored — because repeating things is dull.
- I’m easily distracted (when I’m bored).
- I’m German: Of course we strive for perfection and excellence. ;-)
Being on Unix (or Linux) it’s fairly simple to automate things — add some script-fu to bash or csh (or even better zsh) and off you go wrapping things into a small shell script! Then execute again and again!
Before we decided to moved to AWS (and RightScale) in late 2009 we had half a rack of servers (in a Peer1’s POP in NYC) and never did any or much infrastructure automation. We had an image and a set of commands to get a server up and running, but it was far from two mouse-clicks today.
At the time, I had read about cfengine a couple of times, but datacenter-grade infrastructure management along with a rather steep learning wall (at that time anyway) seemed overkill. Add to that, that there is not a lot of time for research Fridays when you work in a small company.
Moving to AWS and RightScale required us to write lots of small shell scripts using bash and Ruby. When we moved from RightScale to Scalarium in late 2010, we went from shell scripts to Chef.
Using Chef meant that we created so-called recipes which are used to bootstrap our servers. Recipes are little Ruby scripts which live in a cookbook — open source projects are sometimes so creative. Before this move I had very little, or next to no, experience with Chef, and Chef being Ruby didn’t exactly make me want to try it either.
So what exactly is Chef?
A Chef recipe is a tiny bit of Ruby code — essentially a high(er)-level wrapper around calls such as installing certain packages, creating and parsing configuration files and many other things.
Chef offers a robust abstraction about everything you can do with shell and with a little effort it’s also possible to write recipes which run on multiple OS’. Supported are Ubuntu, CentOS, FreeBSD and others. For an intro to Chef see the slides of a talk I gave a couple weeks ago; I briefly blogged about it too.
Our Chef recipes currently include things like installing and configuring PHP (from source and through a launchpad repository), nginx, MySQL, CouchDB, haproxy and many other things. The list was literally growing every day for the first few weeks.