Azure Virtual Machines

Azure Virtual Machines (VMs) provide on-demand, scalable computing resources. You can use Azure VMs to deploy and run applications, host websites, build development and test environments, run large-scale data analytics, and much more.

Key Concepts

What is a Virtual Machine?

A virtual machine is an emulation of a physical computer. Azure VMs run on Microsoft's global network of datacenters and allow you to run your own applications on a virtualized hardware. This gives you the flexibility and power of a dedicated server without the need to manage the underlying physical infrastructure.

VM Sizes

Azure offers a wide range of VM sizes optimized for different workloads. These sizes vary in terms of:

• CPU: Number and type of virtual processors.
• Memory: Amount of RAM available.
• Storage: Options for temporary storage and managed disks (SSD/HDD).
• Network Bandwidth: Throughput for network traffic.

Common VM families include:

• General Purpose (A, D, B series): Balanced CPU-to-memory ratio, suitable for most common workloads like web servers, small to medium databases, and development/test environments.
• Compute Optimized (F series): High CPU-to-memory ratio, ideal for compute-intensive applications like batch processing, web servers, and gaming.
• Memory Optimized (E, G, M series): High memory-to-CPU ratio, best for large relational database servers, in-memory caches, and analytics workloads.
• Storage Optimized (L series): High disk throughput and IOPS, suitable for big data, SQL, and NoSQL databases.
• GPU Optimized (N series): For graphics-intensive workloads, machine learning, and video rendering.

VM Images

You can deploy VMs from various operating system images available in the Azure Marketplace. These include:

• Windows Server (various versions)
• Linux distributions (Ubuntu, CentOS, Red Hat Enterprise Linux, SUSE Linux Enterprise Server, etc.)
• Specialized images for specific applications or configurations.

You can also create and deploy your own custom VM images.

Getting Started

Deploying a VM

You can deploy Azure VMs using several methods:

• Azure Portal: A user-friendly web interface for managing Azure resources.
• Azure CLI: A cross-platform command-line tool.
• Azure PowerShell: A command-line shell and scripting language for managing Azure.
• Azure Resource Manager (ARM) templates: Declarative JSON templates for deploying infrastructure.
• Terraform: A popular open-source Infrastructure as Code tool.

Example using Azure CLI:

az vm create \
  --resource-group MyResourceGroup \
  --name MyVM \
  --image UbuntuLTS \
  --admin-username azureuser \
  --admin-password 'YourPassword123!' \
  --size Standard_DS1_v2 \
  --location eastus
            

Connecting to a VM

Once deployed, you can connect to your VM:

• Windows VMs: Use Remote Desktop Protocol (RDP).
• Linux VMs: Use Secure Shell (SSH).

Connecting to a Linux VM via SSH (example):

ssh azureuser@<public_ip_address>
            

Replace <public_ip_address> with your VM's public IP address.

Key Features and Capabilities

Managed Disks

Managed Disks simplify storage management by handling the underlying storage account creation and management. They are available in several types:

• Ultra Disk: High performance for I/O-intensive workloads.
• Premium SSD: Low latency, high throughput for production workloads.
• Standard SSD: Consistent performance for web servers and lightly-to-moderately interactive applications.
• Standard HDD: Cost-effective for development/test, backup, and non-critical workloads.

Availability and Resiliency

Azure VMs can be deployed into Availability Sets and Availability Zones to ensure high availability and protect against planned and unplanned maintenance and hardware failures.

Networking

VMs can be configured with virtual network interfaces (NICs) connected to Azure Virtual Networks (VNet), allowing for secure and flexible network configurations, including:

• Network Security Groups (NSGs) for traffic filtering.
• Load balancing with Azure Load Balancer or Application Gateway.
• Private IP addressing and custom DNS.

Scalability

You can scale VMs vertically (changing VM size) or horizontally (adding more VM instances using Virtual Machine Scale Sets) to meet changing demand.

Common Use Cases

• Hosting web applications and APIs.
• Running enterprise applications like SAP, Oracle, and Microsoft SQL Server.
• Development and testing environments.
• Disaster recovery solutions.
• Big data analytics.
• High-performance computing (HPC).

Explore the Azure documentation for detailed guides on creating, managing, and optimizing your Azure Virtual Machines.

Last Updated: October 27, 2023