Book Image

Puppet Cookbook - Third Edition - Third Edition

Book Image

Puppet Cookbook - Third Edition - Third Edition

Overview of this book

This book is for anyone who builds and administers servers, especially in a web operations context. It requires some experience of Linux systems administration, including familiarity with the command line, file system, and text editing. No programming experience is required.
Table of Contents (12 chapters)
11
Index

Making quick edits to config files


When you need to have Puppet change a particular setting in a config file, it's common to simply deploy the whole file with Puppet. This isn't always possible, though; especially if it's a file that several different parts of your Puppet manifest may need to modify.

What would be useful is a simple recipe to add a line to a config file if it's not already present, for example, adding a module name to /etc/modules to tell the kernel to load that module at boot. There are several ways to do this, the simplest is to use the file_line type provided by the puppetlabs-stdlib module. In this example, we install the stdlib module and use this type to append a line to a text file.

Getting ready

Install the puppetlabs-stdlib module using puppet:

t@mylaptop ~ $ puppet module install puppetlabs-stdlib
Notice: Preparing to install into /home/thomas/.puppet/modules ...
Notice: Downloading from https://forgeapi.puppetlabs.com ...
Notice: Installing -- do not interrupt ....