There are many benefits to implementing a declarative configuration tool like Puppet into your environment — most notably consistency and automation.

Consistency. Troubleshooting problems with servers is a time-consuming and manually intensive process. Without configuration management, you are unable to make assumptions about your infrastructure — such as which version of Apache you have or whether your colleague configured the machine to follow all the manual steps correctly. But when you use configuration management, you are able to validate that Puppet applied the desired state you wanted. You can then assume that state has been applied, helping you to identify why your model failed and what was incomplete, and saving you valuable time in the process. Most importantly, once you figure it out, you can add the missing part to your model and ensure that you never have to deal with that same problem again. Automation. When you manage a set of servers in your infrastructure, you want to keep them in a certain state. If you only have to manage homogeneous 10 servers, you can do so with a script or by manually going into each server. In this case, a tool like a Puppet may not provide much extra value. But if you have 100 or 1,000 servers, a mixed environment, or you have plans to scale your infrastructure in the future, it is difficult to do this manually. This is where Puppet can help you — to save you time and money, to scale effectively, and to do so securely.

Key concepts behind Puppet Using Puppet is not just about the tool, but also about a different culture and a way of working. The following concepts and practices are key to using and being successful with Puppet.

Infrastructure-as-code Puppet is built on the concept of infrastructure-as-code, which is the practice of treating infrastructure as if it were code. This concept is the foundation of DevOps — the practice of combining software development and operations. Treating infrastructure as code means that system administrators adopt practices that are traditionally associated with software developers, such as version control, peer review, automated testing, and continuous delivery. These practices that test code are effectively testing your infrastructure. When you get further along in your automation journey, you can choose to write your own unit and acceptance tests — these validate that your code, your infrastructure changes, do as you expect.