3.4.3. 💡 First Principle: Infrastructure as Code (IaC) and ARM Templates

First Principle: Infrastructure as Code (IaC) is the practice of managing and provisioning infrastructure through machine-readable definition files. Its core purpose is to enable automation, consistency, and repeatability in deployments, treating infrastructure with the same rigor as application code.

What It Is: IaC is a key DevOps practice that involves managing your IT infrastructure using configuration files.

• Azure Resource Manager (ARM) Templates:
  • Description: JSON files that define the infrastructure and configuration for your Azure solution. ARM is the native deployment and management service for Azure.
  • Declarative Syntax: You define what you want to deploy, and ARM figures out how to create it. For example, you declare "I want a VM with these specs," and ARM handles the provisioning steps.
  • Idempotent: Running the same template multiple times results in the same state, preventing duplicate resources.

Scenario: A development team needs to be able to quickly and reliably deploy their application's entire infrastructure (VMs, network, database) to a new environment for testing. They want to ensure the test environment is an exact replica of the production environment.

Reflection Question: How do ARM templates enable this team to achieve consistent and repeatable deployments of their infrastructure?

💡 Tip: ARM templates are the native way to do Infrastructure as Code in Azure. They are the language that the Azure Portal itself uses behind the scenes when you create resources.