Azure Resource Manager (ARM)

Azure Resource Manager (ARM) is the deployment and management service for Azure. It provides a management layer that enables you to create, update, and delete resources in your Azure account. You can use ARM templates to define the infrastructure for your application, and then deploy that infrastructure consistently and repeatedly.

Key Concepts

Resources

A resource is a manageable item that is available through Azure. Common examples of resources include virtual machines, storage accounts, virtual networks, and web apps.

Resource Groups

A resource group is a logical container that holds related resources for an Azure solution. The resource group can include all the resources for the solution, or only those resources that you want to manage as a group. You decide how to allocate resources to resource groups based on what makes the most sense for your organization.

ARM Templates

ARM templates are JSON files that define the infrastructure and configuration of your Azure solution. They allow you to declaratively deploy your resources. With ARM templates, you can:

Define the types and configurations of resources needed for your application.
Deploy resources in a consistent and repeatable manner.
Manage dependencies between resources.
Use parameters and variables to customize deployments.

Declarative vs. Imperative

ARM is declarative, meaning you describe the desired state of your resources, and ARM figures out how to achieve that state. This is in contrast to imperative management, where you script the exact commands to execute.

Common Operations

Deploying Resources

You can deploy ARM templates using the Azure portal, Azure CLI, Azure PowerShell, or REST API.

Example using Azure CLI:

az deployment group create --resource-group myResourceGroup --template-file azuredeploy.json --parameters azuredeploy.parameters.json

Managing Resources

Once resources are deployed, you can manage them through the Azure portal, CLI, PowerShell, or SDKs. This includes updating resource properties, deleting resources, and managing access.

Tip: Always scope your deployments to resource groups. This makes it easier to manage, monitor, and delete related resources together.

Resource Locks

Resource locks prevent accidental deletion or modification of critical resources. You can apply locks at the subscription, resource group, or individual resource level.

Getting Started with ARM Templates

To start creating ARM templates:

Familiarize yourself with the ARM template schema.
Use the Azure portal to export existing resource group templates to understand their structure.
Write your own templates for common deployment scenarios.
Test your templates thoroughly.

For more detailed information, refer to the official ARM template documentation.