Book Image

Extending Puppet - Second Edition

By : Alessandro Franceschi, Jaime Soriano Pastor
Book Image

Extending Puppet - Second Edition

By: Alessandro Franceschi, Jaime Soriano Pastor

Overview of this book

Puppet has changed the way we manage our systems, but Puppet itself is changing and evolving, and so are the ways we are using it. To tackle our IT infrastructure challenges and avoid common errors when designing our architectures, an up-to-date, practical, and focused view of the current and future Puppet evolution is what we need. With Puppet, you define the state of your IT infrastructure, and it automatically enforces the desired state. This book will be your guide to designing and deploying your Puppet architecture. It will help you utilize Puppet to manage your IT infrastructure. Get to grips with Hiera and learn how to install and configure it, before learning best practices for writing reusable and maintainable code. You will also be able to explore the latest features of Puppet 4, before executing, testing, and deploying Puppet across your systems. As you progress, Extending Puppet takes you through higher abstraction modules, along with tips for effective code workflow management. Finally, you will learn how to develop plugins for Puppet - as well as some useful techniques that can help you to avoid common errors and overcome everyday challenges.
Table of Contents (19 chapters)
Extending Puppet Second Edition
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface
Index

Restoring files from a filebucket


Puppet, by default, makes a local copy of all the files that it changes on a system; it allows the recover old versions of files overwritten by Puppet. This functionality is managed with the filebucket type, which allows to store a copy of the original files, either on a central server or locally on the managed system.

When we run Puppet, we see messages like this:

info: /Stage[main]/Ntp/File[ntp.conf]: Filebucketed /etc/ntp.conf to puppet with sum 7fda24f62b1c7ae951db0f746dc6e0cc

The checksum of the original file is useful to retrieve it; in fact files are saved in the directory /var/lib/puppet/clientbucket in a series of subdirectories named according to the same checksum. So, given the preceding example, our file contents are saved in:

/var/lib/puppet/clientbucket/7/f/d/a/2/4/f/6/7fda24f62b1c7ae951db0f746dc6e0cc/contents

We can verify the original path in:

/var/lib/puppet/clientbucket/7/f/d/a/2/4/f/6/7fda24f62b1c7ae951db0f746dc6e0cc/paths

A quick way to look for the saved copies of a file, therefore, is to use a command like this:

grep -R /etc/ntp.conf /var/lib/puppet/clientbucket/

Puppet provides the filebucket subcommand to retrieve saved files. In the preceding example, we can recover the original file with a (not particularly handy) command like:

puppet filebucket restore -l --bucket /var/lib/puppet/clientbucket /etc/ntp.conf 7fda24f62b1c7ae951db0f746dc6e0cc

It's possible to configure remote filebucket, typically on the Puppet Master using the special filebucket type:

filebucket { 'central':
  path   => false,    # This is required for remote filebuckets.
  server => 'my.s.com', # Optional, by default is the puppetmaster
}

Once declared filebucket, we can assign it to a file with the backup argument:

file { '/etc/ntp.conf':
  backup => 'central',
}

This is generally done using a resource default defined at top scope (typically in our /etc/puppet/manifests/site.pp):

File { backup => 'central', }