Rhett - Learning Puppet 4 a guide to configuration management and automation

by Jo Rhett

Copyright 2016 Jo Rhett. All rights reserved.

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978-1-491-90766-5

[LSI]

I first met Jo Rhett online in the early 2000s. We were both active on the CFengine mailing lists, trying to administer production systems with methodologies that would come to be known as infrastructure as code. At the time, the concept of repeatable, convergent automation tools was fairly edgy, and the community that arose around the space also had its sharp edges. I seem to recall standing up at a LISA config management birds-of-a-feather session circa 2003, pointing at Mark Burgess, CFengines author, and shouting, You ruined my life! But you saved my life!

Luke Kanies was also a CFengine user at the time, and was consistently exhorting the community to introspect its shortcomings and evolve to the next level. His edginess led to some pretty epicthough mostly collegialdebates, borne out in papers such as Steve Traugotts Turing Equivalence in Systems Administration and Lukes ISConf: Theory, Practice, and Beyond.

Around 2005, Luke began writing a new tool in Ruby that was intended to address the problems with usability and flexibility he was running into with the rest of the ecosystem. Originally called Blink, the thing we know today as Puppet began its infancy as a CFengine module (actually a plugin, thus perpetuating an unfortunate relationship with English names that Puppet continues to this day), and Jo and I, along with the rest of the nascent configuration management community, followed its development with interest.

Fast-forward several years through a few iterations of Moores law, and witness the resultant explosion in processing power, distributed systems complexity, and their attendant burden on operations folk. Puppet had matured to become the dominant lingua franca of infrastructure; the tool wars of the mid-2000s had achieved dtente and our focus turned to culture, process, and the wider problems of tying infrastructure operations to business value: in a word, DevOps.

Id done tens of thousands of infrastructure buildouts on Puppet and eventually came to work at Puppet Labs, the company Luke formed around supporting and productizing Puppet. Jo was consulting at large companies around Silicon Valley, pushing Puppet to its limits and feeding bug fixes and feature requests into the community. As Puppets new product manager, this relationship was a little different (and frankly, sometimes far less comfortable, on my end!) than working as peers on the same project, but over the past several years its turned out to be hugely positive.

The thing I appreciate most about Jo, which I think shines through in the book youre about to read, is his sincere desire to help others. This is a core principle of the DevOps movement, usually stated as sharing or empathy, and Jos embodied it since the early days of CFengine. He consistently advocates for the tough right thing for the users, and while he will describe a range of possibilities with deep technical acumen and clear-eyed candor, in the end hell steer us, the readers, in the direction thats going to work out the best in the long term.

Puppets an amazing tool, but as the saying goes: With great power comes great responsibility. Jos depth of experience and empathy for other operations engineers make him the right person to show us how to use Puppets power responsibly. This book is the result, and Im deeply grateful to him for writing it.

Eric Sorenson

Technical Product Manager

Puppet Platform

Portland, Oregon, September 24, 2015