Until now, nothing you have built has cost any money. That changes with the next lesson: whatever runs in Azure costs money for as long as it exists, some of it even when nobody uses it. That's why this lesson comes before the first deploy. You clarify where your resources will be created, set up a budget with alerts, and write down what the Kladde needs in Azure and which of it is free.

In this lesson you write no code. You work in the Azure portal and write a file docs/operations.md.

Tenant, subscription, resource group, region

Four terms organize everything you create in Azure:

  • You know the tenant from lesson 2.6.2: the Microsoft Entra ID directory with users, groups and app registrations. It answers the question “Who is who?”
  • A subscription is the unit that Azure bills costs to and applies limits to. Every resource belongs to exactly one subscription. A tenant can have several subscriptions; a subscription trusts exactly one tenant.
  • A resource group collects resources that are created together and disappear together. If you delete the group, everything in it is gone. That's exactly how azd cleans up in lesson 2.9.5.
  • A region is a location with data centers, such as germanywestcentral (Frankfurt) or swedencentral. Every resource lives in one region.

Everything you create, change or delete in Azure goes through one shared interface, the Azure Resource Manager. The portal uses it, azd uses it, and the Bicep templates that Aspire generates from the AppHost for azd are instructions to it. You write Bicep yourself in K3.

A region in the EU

The Kladde manages contacts and bookings of people in Germany. So put it in a region in the EU, close to the people who use it: the data stays in the EU, and the distances are short. For this course, germanywestcentral, swedencentral, westeurope (the Netherlands) and northeurope (Ireland) are suitable.

Not every service and not every offer exists in every region. Stick to one region for everything that belongs to the Kladde. For the free tier of Azure SQL Database, Microsoft also points out that the region of the first free database may apply to all further free databases in the subscription. Changing it later is then a hassle.

The terms in this section are also part of the AZ-900 exam (Azure Fundamentals). This course doesn't fully prepare you for it; it lays part of the groundwork.