AZ-900: Microsoft Azure Fundamentals

Infrastructure as a Service (IaaS) provides virtualized computing resources over the internet. You rent virtual machines, storage, and networking on demand and pay only for what you use, which reduces upfront hardware costs and lets you scale quickly. In Azure, the three main component categories are virtual machines, storage, and networking.

High availability means your applications are designed to stay running even if parts of the system fail. Azure achieves this by spreading resources across multiple, physically separate locations called datacenters within a region. If one datacenter has a problem, traffic automatically flows to another. This setup reduces downtime and keeps services accessible to users. Scalability is the ability of a system to handle changes in demand. You can add more resources, like processing power or memory, to handle growth. This is called scaling up. You can also add more copies of a resource, like adding more virtual machines to a pool, which is called scaling out. The cloud makes scaling fast and easy, so you only pay for what you need when you need it.

Azure’s global physical structure is organized into a hierarchy designed to keep services resilient and close to users. At the base are regions, which are geographical areas containing one or more datacenters connected through a low‑latency network. Within regions, Azure provides availability zones—physically separate datacenters with independent power, cooling, and networking. To manage these resources logically, users place them into a resource group, which acts as a container for organizing and securing related assets. This physical and logical structure helps organizations meet performance goals and comply with data residency rules by choosing exactly where data is processed and stored.

Microsoft Entra ID is a cloud-based directory and identity management service that acts as the backbone for authentication and authorization in Azure. When you sign up for an Azure subscription, a dedicated Entra ID tenant—the organization’s own instance of the service—is created automatically. The tenant contains users, groups, and applications, and you can add custom domains like contoso.com to make sign-in names familiar. Each Azure subscription is linked to one Entra tenant, which establishes a trust relationship between billing and identity. Administrators use user and group management to organize access, assign roles such as Global Administrator or Privileged Role Administrator, and control subscription settings. Single sign-on (SSO) lets users sign in once and access multiple cloud and on-premises apps without repeated passwords, and integration with on-premises directories via Microsoft Entra Connect synchronizes user accounts and credentials for a hybrid identity approach.

An Azure region is a geographic area that contains multiple datacenters working together to deliver cloud services. Each region provides local access to Azure services, which helps reduce network latency and improve performance for users closest to that region. When you deploy resources in Azure, you choose which region they live in, and this choice affects both speed and compliance. Selecting a region near your users keeps resources nearby and improves response times, making applications feel faster and more reliable.

Azure Table Storage is a NoSQL service for storing structured, non-relational data. It uses a schemaless design, meaning you can store different types of data in the same table without a fixed structure, which makes it easy to adapt as your application changes. Data is organized into tables inside a storage account, where each table contains entities (like rows) with simple name-value pair properties. It is a cost-effective choice for storing large volumes of data that don't require complex relationships, such as user profiles or device information.

Azure offers three main compute options: Virtual Machines, Containers, and Functions. Choosing the right one involves balancing cost, performance, and how much management work you are willing to do. Virtual Machines provide the most control but require you to manage the operating system, including patching and security. You pay a constant rate based on running time and the size of the machine.

Before deploying cloud services, you should estimate your potential expenses using tools like the Azure Pricing Calculator to prevent unexpected bills. Several factors directly influence your bill. Region selection matters because prices vary across geographic locations due to local infrastructure costs. Resource size, like the number of CPU cores in a virtual machine, and resource type, such as compute or storage, determine which billing meters apply.

Microsoft Purview is a service that helps organizations manage and govern their data across different locations. It gives a unified view of all data, no matter where it lives—whether in Azure, in other clouds, or on local computers. Purview finds data automatically, classifies it (like tagging personal information as private), and shows who can access it. This helps companies follow rules about data privacy and make sure sensitive information is protected.

The Azure portal is a web-based, graphical user interface (GUI) that allows you to manage your Azure subscription and resources. Through a single console, users can build, manage, and monitor everything from simple web apps to complex cloud deployments. The portal features customizable dashboards, which let you organize and view your most important resources in one place. It also includes a search bar to quickly locate services, resources, and help. Because it is highly visual, the Azure portal is the ideal starting point for beginners or for performing manual, one-off administrative tasks.

Azure Advisor is a free, built-in service that scans your Azure environment and gives personalized recommendations to improve your workloads. It looks at four areas: reliability, security, performance, and cost. Advisor compares your resource configuration against best practices and then suggests actions you can take, such as moving an underused virtual machine to a smaller size to save money or enabling geo-redundant storage for better disaster recovery. You can view the recommendations in the Azure portal and either apply them directly or dismiss items that do not apply. Advisor helps you stay proactive so you can avoid problems before they happen and get the most value from your Azure subscription.