# Define rack fault domains before enabling campus-cluster storage

> What topology evidence is required before enabling S2D in a campus cluster?

- Canonical URL: https://update.dsesecurity.com/updates/dse-20260908-183-define-rack-fault-domains-before-enabling-campus-cluster-storage/
- Publisher: Detection Systems & Engineering (DSE Security)
- Author: DSE Security Editorial Team
- Published: 2026-09-08T18:14:08+00:00
- Modified: 2026-09-08T18:26:32+00:00
- Last reviewed by DSE: 2026-09-08
- Resource type: Guide
- DSE priority: Information
- Topics: Business Continuity, IT
- Reading time: 2 minutes

## What you need to know

What topology evidence is required before enabling S2D in a campus cluster?

## Potentially affected

Administrators creating the documented Windows Server Storage Spaces Direct campus-cluster topology.

## DSE recommendation

Have facilities and storage owners review a rack map that identifies every node, power source, network dependency, and the separate witness location.

## Article

## Source facts

Microsoft describes a campus cluster as nodes and data distributed across two physical racks in separate rooms or buildings on one campus. Its procedure requires defining the two rack fault domains before enabling Storage Spaces Direct. After enablement, the documented verification checks that the storage pool reports StorageRack for FaultDomainAwareness. [Microsoft Learn](https://learn.microsoft.com/en-us/windows-server/failover-clustering/create-storage-spaces-direct-campus-cluster).

## Applicability

Check the current prerequisites in full, including the Windows build and update, supported drive configuration, balanced node placement, and witness location. Match the logical rack names to the actual physical layout. Do not adapt the example solely from the total node count.

## DSE recommendation

Have facilities and storage owners review a rack map that identifies every node, power source, network dependency, and the separate witness location. Record the intended rack membership before storage enablement and obtain a second-person check of the mapping. Define an approved rack-loss acceptance exercise with the application owner. Keep the topology record with the cluster configuration rather than in an unrelated floor plan.

## Verification

Verify each node belongs to the intended rack domain and inspect the pool fault-domain-awareness value. Compare the observed placement with the signed-off map. In an approved environment, exercise the chosen rack-failure scenario and validate application behavior and recovery. Resolve incorrect rack membership before treating the cluster as rack-resilient.

## Official references

[Microsoft Learn: Create a Storage Spaces Direct Campus Cluster](https://learn.microsoft.com/en-us/windows-server/failover-clustering/create-storage-spaces-direct-campus-cluster). Source reviewed September 8, 2026.

## Primary reference

- Name: Create a Storage Spaces Direct Campus Cluster
- Authority: Microsoft Learn
- URL: https://learn.microsoft.com/en-us/windows-server/failover-clustering/create-storage-spaces-direct-campus-cluster
- Source publication date: Not stated by the source

## Citation and use

Preferred citation: “Define rack fault domains before enabling campus-cluster storage,” DSE Security, https://update.dsesecurity.com/updates/dse-20260908-183-define-rack-fault-domains-before-enabling-campus-cluster-storage/
Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/
Usage and citation policy: https://update.dsesecurity.com/usage/
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