WIndows Clustering

• Introduction
• Azure Local (formerly Azure Stack HCI)
  • Key characteristics and features
  • Azure Local Use cases
• Traditional WSFC with External SAN/NAS Storage
  • Key characteristics and features
  • Traditional WSFC Use cases
• Windows Server Failover Clustering with Storage Spaces Direct (S2D)
  • Key characteristics and features
  • WSFC with S2D Use cases
• Comparative Analysis of the Three Solutions
  • Comparison Matrix
  • Azure Local – Pros and Cons
  • Traditional WSFC + SAN – Pros and Cons
  • WSFC + Storage Spaces Direct – Pros and Cons
• Industry and Workload Considerations
  • Industry Examples
  • Workload Examples
• Optional Azure Integration for WSFC (SAN or S2D) Clusters
• Decision Framework – Choosing the Right Approach
• Conclusion

Introduction

In modern Windows infrastructure, there are multiple strategies for building highly available clusters. This content, originally published as a blog, was adapted into a presentation for a session at MMS MOA 2025, To Windows Server or Not: The Clustering Question, where the PowerPoint version is available. The session compares three key solutions side-by-side: Azure Local (Azure Stack HCI), Windows Server Failover Clustering with External Storage (traditional 3-tier architecture using SAN/NAS), and Windows Server Failover Clustering with Storage Spaces Direct (S2D). We explore the technical architecture of each, their pros and cons, and strategic considerations. Key factors like cost, scalability, performance, hardware needs, manageability, cloud integration, licensing, and best-fit use cases are analyzed with comparison tables for clarity. A dedicated section on demo scenarios is included to showcase strengths and differences in a lab environment. Finally, we provide a decision framework to guide choosing the right approach based on an organization’s needs.