Azure Resource Manager and Resource Groups

Every resource you create in Azure — a VM, a database, a storage account — is managed through Azure Resource Manager (ARM). Understanding ARM and how resources are organised is fundamental to working with Azure.

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What Is Azure Resource Manager?

Azure Resource Manager is the deployment and management layer for Azure. When you create, update, or delete a resource (via the portal, CLI, PowerShell, SDKs, or REST API), your request is sent to ARM, which handles authentication, authorisation, and the actual operation.

Azure Portal / CLI / PowerShell / SDK
         |
         v
  Azure Resource Manager (ARM)
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         v
   Azure Service (Compute, Storage, etc.)

Benefits of ARM

• Consistent management layer — all tools (portal, CLI, SDK) go through the same API
• Declarative templates — define infrastructure as code using ARM templates or Bicep
• Dependency management — ARM deploys resources in the correct order based on dependencies
• Tagging — apply metadata to resources for organisation and cost tracking
• Access control — Azure RBAC is applied at the ARM level
• Resource locking — prevent accidental deletion or modification

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Resource Groups

A resource group is a logical container that holds related Azure resources. Every Azure resource must belong to exactly one resource group.

Key Rules

• A resource can only be in one resource group at a time
• Resource groups cannot be nested (you can't put a resource group inside another)
• You can move resources between resource groups
• A resource group can contain resources from different regions
• Deleting a resource group deletes all resources inside it

Organising Resource Groups

There is no single "right" way to organise resource groups. Common strategies include:

Strategy	Example
By environment	rg-prod, rg-dev, rg-staging
By application	rg-webapp, rg-api, rg-data
By lifecycle	Group resources that are created and deleted together
By department	rg-marketing, rg-engineering

Resource Group Location

When you create a resource group, you specify a location. This is where the resource group's metadata is stored — it does not restrict where the resources inside it can be deployed.

# Create a resource group in UK South
az group create --name rg-demo --location uksouth

# Create a VM in East US within that resource group
az vm create --resource-group rg-demo --location eastus --name myVM --image Ubuntu2204

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Subscriptions