Azure compute and networking services
📘Microsoft Certified: Azure Fundamentals (AZ-900)
Application Hosting in Azure
In Azure, application hosting means running your software or services so users can access them over the internet or a network. Azure provides multiple ways to host applications, and the main ones are:
- Web Apps (Platform as a Service, PaaS)
- Containers (Lightweight, portable apps)
- Virtual Machines (Infrastructure as a Service, IaaS)
Each option has its own features, use cases, and management responsibilities.
1. Azure Web Apps
- Type: PaaS (Platform as a Service)
- Purpose: To run websites or web applications without managing the underlying infrastructure like servers or operating systems.
- Key Features for AZ-900 Exam:
- Fully managed by Azure.
- Supports multiple programming languages (e.g., .NET, Java, Python, PHP, Node.js).
- Auto-scaling: Azure can automatically increase or decrease resources depending on demand.
- Built-in high availability and security.
- Deployment options: directly from GitHub, Azure DevOps, or local code.
Who manages what:
- Azure: handles the server, OS, and infrastructure.
- You: manage your application code and configuration.
Use in IT environments:
- Hosting a corporate internal portal.
- Running a SaaS web application.
- Hosting APIs that mobile or web apps consume.
2. Containers
- Type: Can run as PaaS or part of IaaS.
- Purpose: Containers are lightweight packages that include your application and everything it needs to run. This makes them portable and consistent across environments.
Key Features for AZ-900 Exam:
- Can run in Azure using Azure Kubernetes Service (AKS), Azure Container Instances (ACI), or on VMs.
- Containers isolate applications so multiple containers can run on the same host without conflicts.
- Faster to start and more efficient than full virtual machines.
- Supports DevOps and CI/CD pipelines for continuous deployment.
Who manages what:
- Azure manages the container service (if using AKS or ACI).
- You manage the containerized application and its configurations.
Use in IT environments:
- Running microservices (small, independent components of an application).
- Quickly deploying updates without affecting other apps.
- Testing new software in isolated environments before production.
3. Virtual Machines (VMs)
- Type: IaaS (Infrastructure as a Service)
- Purpose: Virtual machines are full servers running in the cloud. You control almost everything, just like having a physical server in a data center.
Key Features for AZ-900 Exam:
- Choose OS: Windows or Linux.
- Full control over software installation and configuration.
- Flexible sizes: from small testing machines to large production servers.
- Can be connected to networks, storage, and other Azure resources.
- Can be used for legacy applications that need full server control.
Who manages what:
- You manage the operating system, applications, updates, and security.
- Azure manages the physical server, storage, networking, and virtualization layer.
Use in IT environments:
- Running custom enterprise applications.
- Hosting databases.
- Running background services or batch processing jobs.
Comparing Web Apps, Containers, and VMs
| Feature | Web Apps (PaaS) | Containers | VMs (IaaS) |
|---|---|---|---|
| Management | Azure manages most | Shared: Azure + You | You manage most |
| Ease of Use | High | Medium | Low |
| Scaling | Auto-scaling | Manual or auto | Manual |
| Portability | Limited | High | Low |
| Best For | Web applications | Microservices, DevOps | Legacy apps, full server control |
| Cost | Pay for app usage | Pay per container | Pay per VM size |
Exam Tip: You should be able to identify the correct hosting option based on the scenario.
- If you need minimal management, choose Web Apps.
- If you want portable apps or microservices, choose Containers.
- If you need full control of the OS or legacy software, choose VMs.
Key Azure Services for Application Hosting
- Azure App Service → Web Apps (PaaS)
- Azure Container Instances (ACI) → Run containers quickly without managing VMs
- Azure Kubernetes Service (AKS) → Orchestrate and manage multiple containers at scale
- Azure Virtual Machines → Full control over infrastructure
Exam Pointers for AZ-900
- PaaS vs IaaS: Know the difference in management responsibility.
- Web Apps vs Containers: Web Apps are simpler; Containers are portable and flexible.
- VMs: Give maximum control but require more management.
- Remember Azure manages infrastructure for PaaS and partially for containers, but you manage it all in VMs.
- Understand use cases; exam questions often describe a scenario and ask which hosting model is best.
