Mastering Puppet - Second Edition

Creating an example CDN role

We will start by constructing a module for a web server (this example is a cliché). What is a web server? Is a web server an Apache server or a Tomcat server or both, or maybe even Nginx? What file systems are required? What firewall rules should be applied, always? The design problem is figuring out what the commonalities are going to be and where to divide them. In most enterprises, creating a blanket "web server" module won't solve any problems and will potentially generate huge case statements. If your modules follow the roles-and-profiles design pattern, you shouldn't need huge case statements keyed off $::hostname; nodes shouldn't be mentioned in your role module. To elaborate this point further, let's take a ...