Introduction to Azure Virtual Machines

Azure Virtual Machines (VMs) provide on-demand, scalable computing resources. You can deploy and run applications on the go with the flexibility of virtualization without having to buy and maintain the physical hardware that supports them.

Azure VMs offer:

  • Flexibility: Choose from a wide range of operating systems, including Windows and Linux.
  • Scalability: Easily scale your compute resources up or down based on demand.
  • Cost-Effectiveness: Pay only for what you use with various pricing options.
  • Global Reach: Deploy VMs in datacenters around the world.

Getting Started with Azure VMs

Deploying your first Azure VM is straightforward. You can use the Azure portal, Azure CLI, or Azure PowerShell.

Using the Azure Portal

  1. Sign in to the Azure portal.
  2. Navigate to "Virtual machines" and click "+ Create".
  3. Fill in the required details: Subscription, Resource Group, VM name, Region, Image, Size, Username, and Password.
  4. Configure networking, disks, and other settings as needed.
  5. Review and create the VM.

Using Azure CLI

az vm create \
  --resource-group MyResourceGroup \
  --name MyVM \
  --image UbuntuLTS \
  --admin-username azureuser \
  --admin-password myPassword123!

For more detailed instructions, refer to the Azure CLI VM creation guide.

Understanding Virtual Machine Concepts

Before deploying VMs, it's important to understand key concepts.

VM Sizes

Azure offers a wide variety of VM sizes, categorized into families like general purpose, compute optimized, memory optimized, storage optimized, and GPU optimized. Each size has a different combination of CPU, memory, storage, and networking capabilities.

Family Example Sizes Use Cases
General Purpose (B, D, A) Standard_B1s, Standard_D2s_v3 Web servers, small to medium databases, development/test environments.
Compute Optimized (F) Standard_F2s_v2 High-performance computing (HPC), gaming, batch processing.
Memory Optimized (E, M) Standard_E4s_v3, Standard_M128s Large relational database servers, in-memory analytics, big data processing.
Storage Optimized (Lsv2) Standard_L8s_v2 Big data, distributed storage, high I/O and throughput.
GPU Optimized (N) Standard_NC6 AI, machine learning, deep learning, scientific simulations.

See the full list of VM sizes for detailed specifications.

VM Images

VM images are templates that contain an operating system and optional software. You can choose from Azure's Marketplace images (Windows Server, Ubuntu, Red Hat Enterprise Linux, etc.) or create your own custom images.

Common image types include:

  • Platform Images: Provided by Azure and OS vendors.
  • Custom Images: Images you create from your own VMs or from existing VHDs.
  • Shared Image Gallery: A service for managing and sharing VM images.

VM Disks

Azure VMs use disks for their operating system and data storage. There are two main types of disks:

  • OS Disk: The disk containing the operating system. Managed disks are recommended for OS disks.
  • Data Disks: Additional disks for storing application data.

Disk types available include:

  • Standard HDD: Cost-effective for development/test and non-critical workloads.
  • Standard SSD: Cost-effective for web servers, lightly trafficked applications, and dev/test.
  • Premium SSD: High-performance, low-latency disk for production and performance-sensitive workloads.
  • Ultra Disk: Highest performance for mission-critical, I/O-intensive workloads.

Networking

Azure VMs connect to networks through Network Interface Controllers (NICs). Key networking components include:

  • Virtual Networks (VNet): Your private network in Azure.
  • Subnets: Divisions within a VNet.
  • Public IP Addresses: To access your VM from the internet.
  • Network Security Groups (NSGs): Firewalls to control inbound and outbound traffic.
  • Load Balancers: Distribute traffic across multiple VMs.

Deploying Azure Virtual Machines

You can deploy VMs using various methods:

  • Azure Portal: A user-friendly graphical interface.
  • Azure CLI: Command-line interface for automation and scripting.
  • Azure PowerShell: PowerShell module for scripting and automation.
  • ARM Templates/Bicep: Infrastructure as Code (IaC) for declarative deployments.
  • Terraform: Popular open-source IaC tool.
Tip: For repeatable and manageable deployments, consider using ARM templates or Bicep.

You can also deploy VMs as part of an Availability Set or Availability Zone for high availability.

Managing Your Virtual Machines

Once deployed, you can manage your VMs for performance, scalability, and security.

Monitoring VM Performance

Azure Monitor provides comprehensive monitoring capabilities:

  • Azure Monitor Metrics: Collect and analyze real-time metrics like CPU utilization, disk I/O, and network traffic.
  • Azure Monitor Logs: Collect and analyze diagnostic logs and application logs.
  • VM Insights: Offers a pre-built dashboard for monitoring VM performance and health.

Set up alerts to notify you of performance issues.

Scaling Virtual Machines

Scale your VMs to meet changing demands:

  • Vertical Scaling (Scale Up/Down): Change the size of a VM to a larger or smaller one.
  • Horizontal Scaling (Scale Out/In): Add or remove VM instances using Virtual Machine Scale Sets (VMSS).

VMSS allows for automatic scaling based on predefined rules and schedules.

Securing Your VMs

Implement robust security measures:

  • Access Control: Use Azure RBAC (Role-Based Access Control) to manage permissions.
  • Network Security: Configure NSGs and Azure Firewall.
  • Patch Management: Regularly update your OS and applications. Azure Update Management can automate this.
  • Antimalware: Install and configure antimalware solutions.
  • Disk Encryption: Use Azure Disk Encryption to encrypt OS and data disks.
  • Azure Security Center: Provides a unified view of security posture and advanced threat protection.

Troubleshooting Common VM Issues

When encountering issues, consider these common areas:

  • Connectivity: Check NSG rules, VNet configurations, and public IP associations.
  • Performance: Monitor resource utilization (CPU, memory, disk, network) and identify bottlenecks.
  • Boot Failures: Use Boot Diagnostics in the Azure portal to view screenshots and serial log output.
  • Application Errors: Review application logs and system event logs.

The Azure VM troubleshooting guide offers more in-depth solutions.

Best Practices for Azure VMs

  • Use Managed Disks: They provide better availability and manageability.
  • Deploy in Availability Sets or Zones: For high availability and fault tolerance.
  • Implement Strong Security: Regular patching, NSGs, disk encryption, and RBAC.
  • Monitor Performance: Use Azure Monitor to proactively identify and resolve issues.
  • Automate Deployments: Utilize ARM/Bicep templates or Terraform for consistent deployments.
  • Optimize Costs: Choose appropriate VM sizes, leverage Reserved Instances, and shut down idle VMs.
  • Use Resource Groups: Organize related resources logically.