If you administer a small network built around just a few servers, you may still be doing at least some of the configuration management by hand. You literally move from machine to machine, manually entering updates, changes, or fixes. And your small network may be running several different brands–and vintages–of hardware and software, which complicates the update and repair process.
However, infrastructure consultant John Arundel warns, once you get “[b]eyond ten or so servers, there simply isn’t a choice. You can’t manage an infrastructure like this by hand. If you’re using a cloud computing architecture, where servers are created and destroyed minute-by-minute in response to changing demand, the artisan approach to server crafting just won’t work.”
In his new book, Puppet 3 Beginner’s Guide, Arundel emphasizes: “Manual configuration management is tedious and repetitive, it’s error-prone, and it doesn’t scale well. Puppet is a tool for automating this process.”
Among “UNIX-like systems,” there are at least three major configuration management (CM) packages, including Puppet. The others are Chef and CFEngine, plus a few more competitors. Arundel calls them “all great solutions to the CM problem…it’s not very important which one you choose as long as you choose one.” But he hopes, of course, you will favor Puppet and his well-written how-to guide.
Puppet 3 Beginner’s Guide is structured to help system administrators “start from scratch…and learn how to fully utilize Puppet through simple, practical examples,” he writes.
He places important emphasis on the rapidly closing “divide between ‘devs,’ who wrangle code, and ‘ops,’ who wrangle configurations. Traditionally, the skills sets of the two groups haven’t overlapped much,” he notes. “It was common until recently for system administrators not to write complex programs, and for developers to have little or no experience of building and managing servers.”
Today, system admins are “facing the challenge of scaling systems to enormous size for the web, [and] have had to get smart about programming and automation.” Meanwhile, “[d]evelopers, who now often build applications, services, and businesses by themselves, couldn’t do what they do without knowing how to set up and fix servers,” he says.
Therefore, “[t]he term ‘devops’ has begun to be used to describe the growing overlap between these skill sets…Devops write code, herd servers, build apps, scale systems, analyze outages, and fix bugs. With the advent of CM systems, devs and ops are now all just people who work with code.”
Arundel’s 184-page Puppet 3 Beginner’s Guide offers 10 chapters smoothly structured with headings, short paragraphs, code examples, and other illustrations. He has generated his code examples using the Ubuntu 12.04 LTS “Precise” distribution of Linux. But he explains how to load the software using “Red Hat Linux, CentOS, or another Linux distribution that uses the Yum package system,” as well.
The chapters are:
- Chapter 1, Introduction to Puppet
- Chapter 2, First Steps with Puppet
- Chapter 3, Packages, Files, and Services
- Chapter 4, Managing Puppet with Git
- Chapter 5, Managing Users
- Chapter 6, Tasks and Templates
- Chapter 7, Definitions and Classes
- Chapter 8, Expressions and Logic
- Chapter 9, Reporting and Troubleshooting
- Chapter 10, Moving on Up
That final chapter covers a range of topics, including how to make Puppet code “more elegant, more readable, and more maintainable.” The author offers “links and suggestions for further reading.” And he describes several projects to help you “improve your skills and your infrastructure at the same time.” Those projects, he says, “provide a series of stepping-stones from your first use of Puppet to a completely automated environment.”
Besides Linux, Puppet will run on other several platforms, including Windows and Macs. But there is almost no help for those in Arundel’s book. Essentially, it’s Linux or bust. For other operating systems, you will need to refer to the Puppet Labs website.
It can take a bit of work to get Puppet installed and properly configured. But once you have Puppet running, the Puppet 3 Beginner’s Guide can help you become both a proficient Puppet user and a more efficient, knowledgeable, and versatile system administrator.
— Si Dunn