What are Azure ARM Templates?
Azure Resource Manager (ARM) Templates are JSON-based files that declaratively describe Azure infrastructure. Instead of manually creating resources in the portal, you define the desired state in a template. Azure handles the creation and configuration of all resources in the correct order.
ARM Templates form the foundation for Infrastructure as Code (IaC) in Azure and enable versioned, repeatable, and consistent deployments.
Core Features
- Declarative syntax: Describe the end state, not the steps
- Dependency management: Automatic detection of resource dependencies
- Idempotent deployments: Multiple executions lead to the same result
- Template functions for dynamic values and calculations
- Modularization through linked and nested templates
- What-if previews before deployment
Typical Use Cases
Development and staging environments: Quickly create identical environments for development, test, and production using parameterized templates.
Compliance and governance: Standardized templates ensure all deployments comply with corporate policies. Changes are versioned and reviewed via Git.
Disaster recovery: Infrastructure can be restored in another region from templates within minutes.
Benefits
- No additional costs for using ARM Templates
- Full integration with Azure DevOps and GitHub Actions
- Consistent deployments eliminate manual errors
- Infrastructure documentation as code
Frequently Asked Questions
What is the difference between ARM Templates and Bicep?
Bicep is a domain-specific language (DSL) that compiles to ARM Templates. Bicep offers simpler syntax, better readability, and native tooling support. For new projects, Microsoft recommends Bicep, but ARM Templates continue to be supported.
Can I export existing resources to templates?
Yes, you can export existing resources as ARM Templates via the Azure Portal or CLI. However, these templates should be cleaned up as they often contain unnecessary properties.
How do I version ARM Templates?
ARM Templates should be versioned in a Git repository. Changes can be reviewed via pull requests before being deployed to production.
Can ARM Templates securely manage secrets?
Yes, sensitive values like passwords should be defined as SecureString parameters and referenced from Azure Key Vault. Secrets should never be stored directly in the template.
Integration with innFactory
As a Microsoft Solutions Partner, innFactory supports you with ARM Templates: template development, CI/CD integration, migration from manual deployments, and best practices.
