Azure Virtual Machines give you the flexibility of virtualization without having to buy and maintain physical hardware. Choose from Windows or Linux, multiple VM sizes optimized for different workloads.
What is Azure Virtual Machines?
Azure Virtual Machines is Microsoft Azure’s Infrastructure-as-a-Service (IaaS) computing service that allows you to provision Windows and Linux VMs in seconds. The service provides complete control over the operating system and enables you to run virtually any workload, from classic enterprise applications to modern container orchestration platforms.
Azure offers a wide range of VM series optimized for different workload requirements: B-series for burstable workloads with low CPU utilization, D-series for general purposes, E-series for memory-intensive applications like SAP HANA, F-series for compute-intensive workloads, M-series for extremely large in-memory databases (up to 12 TB RAM), and N-series for GPU-accelerated workloads such as AI training and high-performance computing. Each series offers different sizes, allowing you to tailor your VM precisely to your requirements.
In addition to the classic pay-as-you-go model, Azure offers flexible pricing options: Spot VMs enable cost savings of up to 90% for interruptible workloads such as batch jobs or development environments. Reserved Instances (1 or 3 years) reduce costs for production workloads with predictable utilization by up to 72%. Azure Hybrid Benefit allows you to use existing Windows Server and SQL Server licenses in Azure, significantly reducing migration costs. For maximum high availability, VMs can be deployed in Availability Sets (99.95% SLA) or Availability Zones (99.99% SLA).
Virtual Machines vs. Alternatives
When choosing a cloud solution, the question of alternatives often arises. Virtual Machines competes with comparable services from other cloud providers:
- AWS: EC2
- Google Cloud: Compute Engine
- STACKIT: Compute Engine
While functionality is often similar, the services differ in pricing models, regional availability, and integration ecosystems. Azure particularly excels with enterprise customers using Microsoft stack and hybrid cloud scenarios.
Typical Use Cases
Web Applications and APIs
Hosting web applications with full control over the server stack. Ideal for legacy applications that require specific Windows Server versions or special kernel configurations. With Load Balancer and Availability Zones, you achieve high availability for production-critical systems.
SAP Workloads
Azure is SAP-certified for HANA and NetWeaver. E- and M-series VMs offer up to 12 TB RAM for large SAP HANA databases. With Azure Hybrid Benefit, you can use existing Windows Server licenses and reduce costs.
Windows Server Migration
Migrate existing Windows Server workloads to the cloud without code changes. Azure Migrate assists with assessment and migration. With Azure Hybrid Benefit, you save up to 49% compared to pay-as-you-go pricing.
High-Performance Computing (HPC)
HB- and HC-series VMs with RDMA network and InfiniBand enable tightly-coupled HPC workloads such as simulations, genomic analyses, or computational fluid dynamics. Burst to thousands of cores for batch jobs with Azure CycleCloud.
Dev/Test Environments
Use Azure Dev/Test pricing for development and test environments with up to 55% discount. Auto-shutdown policies save costs outside working hours. Spot VMs reduce costs for short-lived test environments by up to 90%.
Disaster Recovery
Azure Site Recovery replicates on-premises VMs to Azure for business continuity. In an emergency, start workloads in Azure within minutes. Test DR scenarios without production impact.
GPU Workloads for AI and Machine Learning
N-series VMs with NVIDIA Tesla GPUs accelerate deep learning training, inference, and GPU computing. NCv3 for training large models, NDs for distributed training, NV-series for visualization and remote desktops.
Best Practices
VM Sizing with Azure Advisor
Use Azure Advisor for continuous right-sizing recommendations based on actual CPU and memory utilization. Avoid oversizing and reduce costs by an average of 20-30%.
Spot VMs for Batch Jobs
Deploy Spot VMs for fault-tolerant workloads such as batch processing, rendering, or big data analytics. Save up to 90% on workloads that tolerate interruptions.
Reserved Instances for Predictable Workloads
Purchase Reserved Instances (1 or 3 years) for production workloads with predictable utilization. Reduce costs by up to 72% compared to pay-as-you-go.
Proximity Placement Groups for Latency-Sensitive Applications
Use Proximity Placement Groups to place VMs physically close to each other. Reduces network latency for tightly-coupled applications such as databases and application servers.
Managed Disks for Availability and Backup
Use Managed Disks exclusively instead of Unmanaged Disks. Benefit from automatic storage management, snapshots, Azure Backup integration, and higher SLAs.
Auto-Shutdown for Dev/Test Environments
Configure auto-shutdown policies for development and test VMs. Save 50-70% of compute costs through automatic shutdown outside business hours.
Azure Update Manager for Patch Management
Use Azure Update Manager (formerly Update Management) for centralized patch management across all VMs. Automate Windows Updates and Linux package updates with configurable maintenance windows.
Frequently Asked Questions about Azure Virtual Machines
Which VM series should I choose?
The choice depends on your workload: B-series for workloads with low average CPU utilization (web servers, small databases), D-series for general purposes, E-series for memory-intensive applications (SAP HANA, SQL Server), F-series for CPU-intensive workloads (batch processing, analytics), M-series for very large in-memory databases (up to 12 TB RAM), N-series for GPU workloads (AI, rendering). Azure Advisor provides recommendations based on actual utilization.
What are Spot VMs and when should I use them?
Spot VMs use unused Azure capacity at significantly reduced prices (up to 90% cheaper). However, they can be terminated with short notice (30 seconds) when Azure needs the capacity. Ideal for fault-tolerant workloads such as batch jobs, rendering, big data analytics, dev/test environments, or stateless container workloads. Not suitable for production-critical applications without fault tolerance.
Reserved Instances vs. Savings Plans: Which is better?
Reserved Instances (RI) offer up to 72% discount for 1- or 3-year commitments on specific VM sizes and regions. Savings Plans offer similar discounts but are more flexible: they apply to different VM sizes, regions, and even other compute services. Choose RIs for stable workloads with known requirements, Savings Plans for more dynamic environments with changing VM sizes.
How does Azure Hybrid Benefit work?
Azure Hybrid Benefit allows you to use existing Windows Server and SQL Server licenses with active Software Assurance in Azure. Save up to 49% on Windows Server VMs and up to 55% on SQL Server VMs. Red Hat and SUSE Linux subscriptions can also be used. Licenses can be moved between on-premises and Azure, and after 90 days can be used in parallel.
Availability Sets vs. Availability Zones: What’s the difference?
Availability Sets distribute VMs across multiple fault domains and update domains within a datacenter (99.95% SLA). Protects against hardware failures and planned maintenance. Availability Zones are physically separate datacenters within a region (99.99% SLA). Also protects against datacenter failures. Use Availability Zones for highest availability, Availability Sets when zones are not available or extremely low latency is required.
What are Managed Disks and why should I use them?
Managed Disks are the recommended disk type for Azure VMs. Azure automatically manages storage accounts, scaling, and availability. Benefits: higher SLAs (99.999% for Premium SSD), easier snapshots and backups, no storage account limits, simpler replication, integration with Availability Sets/Zones. Unmanaged Disks should no longer be used.
Are GPUs available in all regions?
No, N-series VMs with GPUs are only available in selected regions. In Europe: West Europe, North Europe, UK South. Check availability via the Azure Portal or the Products Available by Region page. GPU quotas often need to be requested separately as they are set to 0 by default.
How does Windows licensing work in Azure?
You have two options: 1) Pay-as-you-go: Windows Server license is included in the VM price, no additional license required. 2) Azure Hybrid Benefit: Use your existing Windows Server licenses with Software Assurance and pay only Linux prices. Similar applies to SQL Server. Each core license with Software Assurance can be used in Azure.
How can I optimize VM costs?
Use these strategies: 1) Right-sizing with Azure Advisor recommendations, 2) Reserved Instances for predictable workloads (up to 72% savings), 3) Spot VMs for fault-tolerant jobs (up to 90% savings), 4) Auto-shutdown for dev/test VMs, 5) Azure Hybrid Benefit for Windows/SQL, 6) B-series for workloads with low average CPU load, 7) Deallocate instead of just Stop (to avoid compute costs), 8) Azure Cost Management for monitoring and budgets.
Can I connect Azure VMs with on-premises infrastructure?
Yes, through multiple options: 1) Site-to-Site VPN for encrypted connection over the internet, 2) ExpressRoute for dedicated private connection with higher bandwidth and reliability (up to 100 Gbps), 3) Point-to-Site VPN for individual client connections. Azure Virtual WAN simplifies hub-and-spoke topologies. For hybrid identity, use Azure AD Connect.
Integration with innFactory
As a Microsoft Solutions Partner, innFactory supports you in integrating and optimizing Azure Virtual Machines. We help with architecture design, migration of on-premises workloads, cost optimization through right-sizing and Reserved Instances, as well as implementation of high-availability and disaster recovery scenarios.
Contact us for a non-binding consultation on Azure Virtual Machines and Microsoft Azure.
