Terraform and Packer

© Elephant Scale

November 25, 2022

Overview

  • IaC (Infrastructure as Code) is one of the most important developments in application deployment in many years. It means that instead of manually configuring your hardware and software infrastructure, you describe all these configurations as code.

  • While every cloud gives you its implementation of it, and while Amazon heavily promotes its version called CloudFormation, Terraform is a maverick who appeared on the scene a few years ago and became more popular than all other IaC implementations. Recently, Google recognized the superiority of Terraform and started using that instead of its tool. This speaks to the importance of learning Terraform.

  • Terraform is open source and can be used on any cloud provider, such as Amazon Web Services, IBM Cloud, Google Cloud Platform, DigitalOcean, Linode, Microsoft Azure, Oracle Cloud Infrastructure, VMware vSphere, OpenStack, and many others.

  • Terraform is declarative and idempotent. These are good design principles, and many competitors have also implemented Terraform ideas, making Terraform a de facto standard.

What you will learn

  • DevOps and IaC
  • How to use Terraform
  • HashiCorp ecosystem

Audience

Duration

3 days

Format

Lectures and hands-on labs. (50%, 50%)

Prerequisites

  • Some background with Unix or Linux including the command line
  • Some knowledge of a programming language such as Java, C#, Python, Node.js, etc.

Lab environment

  • A reasonably modern laptop
  • Unrestricted connection to the Internet. Laptops with overly restrictive VPNs or firewalls may not work properly
  • Chrome browser
    • SSH client for your platform

Detailed Outline

  • Why Terraform

    • The Rise of DevOps
    • What Is Infrastructure as Code?
    • Ad Hoc Scripts
    • Configuration Management Tools
    • Server Templating Tools
    • Orchestration Tools
    • Provisioning Tools
    • The Benefits of Infrastructure as Code
    • How Terraform Works
    • How Terraform Compares to Other IaC Tools
    • Configuration Management Versus Provisioning
    • Mutable Infrastructure Versus Immutable Infrastructure
    • Procedural Language Versus Declarative Language
    • Master Versus Masterless
    • Agent Versus Agentless
    • Large Community Versus Small Community
    • Mature Versus Cutting Edge
    • Using Multiple Tools Together
    • Conclusion

  • Getting Started with Terraform

    • Setting Up Your AWS Account
    • Install Terraform
    • Deploy a Single Server
    • Deploy a Single Web Server
    • Deploy a Configurable Web Server
    • Deploying a Cluster of Web Servers
    • Deploying a Load Balancer
    • Cleanup
    • Conclusion

  • How to Manage Terraform State

    • What Is Terraform State?
    • Shared Storage for State Files
    • Limitations with Terraform’s Backends
    • Isolating State Files
    • Isolation via Workspaces
    • Isolation via File Layout
    • The terraform_remote_state Data Source
    • Conclusion

  • How to Create Reusable Infrastructure with Terraform Modules

    • Module Basics
    • Module Inputs
    • Module Locals
    • Module Outputs
    • Module Gotchas
    • File Paths
    • Inline Blocks
    • Module Versioning
    • Conclusion

  • Terraform Tips and Tricks: Loops, If-Statements, Deployment, and Gotchas

    • Loops
    • Loops with the count Parameter
    • Loops with for_each Expressions
    • Loops with for Expressions
    • Loops with the for String Directive
    • Conditionals
    • Conditionals with the count Parameter
    • Conditionals with for_each and for Expressions
    • Conditionals with the if String Directive
    • Zero-Downtime Deployment
    • Terraform Gotchas
    • count and for_each Have Limitations
    • Zero-Downtime Deployment Has Limitations
    • Valid Plans Can Fail
    • Refactoring Can Be Tricky
    • Eventual Consistency Is Consistent…Eventually
    • Conclusion

  • Production-Grade Terraform Code

    • Why It Takes So Long to Build Production-Grade Infrastructure
    • The Production-Grade Infrastructure Checklist
    • Production-Grade Infrastructure Modules
    • Small Modules
    • Composable Modules
    • Testable Modules
    • Releasable modules
    • Beyond Terraform Modules
    • Conclusion

  • How to Test Terraform Code

    • Manual Tests
    • Manual Testing Basics
    • Cleaning Up After Tests
    • Automated Tests
    • Unit Tests
    • Integration Tests
    • End-to-End Tests
    • Other Testing Approaches
    • Conclusion

  • How to Use Terraform as a Team

    • Adopting IaC in Your Team
    • Convince Your Boss
    • Work Incrementally
    • Give Your Team the Time to Learn
    • A Workflow for Deploying Application Code
    • Use Version Control
    • Run the Code Locally
    • Make Code Changes
    • Submit Changes for Review
    • Run Automated Tests
    • Merge and Release
    • Deploy
    • A Workflow for Deploying Infrastructure Code
    • Use Version Control
    • Run the Code Locally
    • Make Code Changes
    • Submit Changes for Review
    • Run Automated Tests
    • Merge and Release
    • Deploy
    • Putting It All Together
    • Conclusion