Setting Up a Test Environment

The best way to learn is by doing. This chapter will help you quickly spin up an environment for testing so that you can safely experiment without worrying too much. It will provide several configuration examples and tips on how to get things running. This type of environment will also be used throughout this book in several different scenarios.

In brief, the following topics will be covered in this chapter:

• Code organization
• Machine requirements
• Spinning up a new environment

Code organization

While the examples and code listings in this book can be used directly without any supporting material, a companion Git repository is also provided to help you with the setup process and the automation of test environments so that you can follow along easily.

In this section, we're going to explore how that repository is organized, explain some choices that are made in terms of the automation of the test environments, and give some pointers on how to customize them:

.
├── Makefile
├── README.md
├── cache/
├── chapter03/
├── ...
├── chapter14/
└── utils/

The root structure of the repository shown here should be fairly easy to understand:

• One directory per chapter that needs its own test environment (aptly named chapter...

Machine requirements

The machine requirements for this setup can comfortably run on a modern laptop, as long it has CPU virtualization extensions enabled and its operating system is compatible with the software requirements. All the software requirements that are covered here were thought-out. We will be using free and open source software, so no extra cost should be necessary when you try out the test environments.

Hardware requirements

The minimal requirements for the host deploying the provided examples are as follows:

• At least 2 CPU cores
• At least 4 GB of memory
• At least 20 GB of free disk space

With these specifications, you should be able to spin up the test environment without encountering any issues.

Regarding connectivity...

Spinning up a new environment

After you have ensured that all the required software is available on your host, you may proceed with one or both of the following walkthroughs.

Automated deployment walkthrough

This method will abstract all the deployment and configuration details, allowing you to have a fully running test environment with only a couple of commands. You'll still be able to connect to each of the guest instances and change configurations.

The steps to spin up the environment are as follows:

1. Clone this book's repository:

git clone https://github.com/PacktPublishing/Hands-On-Infrastructure-Monitoring-with-Prometheus.git

2. Step into the newly created directory and chapter number:

cd Hands-On-Infrastructure...

Summary

With a test environment at your disposal, you can now inspect, change, and validate configurations without worrying about breaking things. Throughout this book, this approach to testing will be used extensively, because nothing beats experimenting when learning new skills.

In the next chapter, we'll go over the fundamentals of Prometheus metrics. The test environment we just built will be helpful to demonstrate them.

Questions

1. What are the recommended tools to set up a reproducible test environment?
2. Where can you change the default versions of the Prometheus components for the test environment?
3. What is the default subnet that's used on all examples?
4. At a high level, what are the steps to get a Prometheus instance up and running?
5. Node Exporter is installed on every guest instance. How can you quickly validate if all of them are exposing metrics correctly?
6. In our test environment, where can you find the alert log?
7. How can you create a clean test environment from scratch?

Further reading

• Bash manual: https://www.gnu.org/software/bash/manual/html_node/index.html
• Recommended Vagrant boxes: https://www.vagrantup.com/docs/boxes.html