VMware Cloud Foundation (VCF) 9.1 introduces one of the most significant sets of enhancements to vSAN in recent years. Building on the performance advantages of vSAN Express Storage Architecture (ESA), this release focuses heavily on cyber resilience, operational simplicity, storage efficiency, and enterprise scalability. Whether you're modernizing traditional virtualized workloads, supporting Kubernetes applications, or strengthening your ransomware recovery strategy, vSAN 9.1 delivers compelling new capabilities.
Let's take a closer look at what's new.
Enhanced Data Protection with Auto RAID-6
One of the standout improvements in vSAN ESA is the introduction of Auto RAID-6 as the default RAID configuration.
Traditionally, administrators needed to evaluate workload requirements and manually select the appropriate RAID level. With VCF 9.1, vSAN automatically configures RAID-6 by default, delivering stronger fault tolerance and higher levels of data protection without sacrificing performance.
This automated approach simplifies deployments while ensuring organizations start with a resilient storage configuration from day one.
Benefits
- Automatic selection of optimal protection levels
- Increased fault tolerance
- Simplified cluster deployment
- No performance compromise with ESA architecture
Cyber Recovery Becomes a First-Class Citizen
Cyber resilience is a central theme throughout the vSAN 9.1 release.
Dedicated Cyber Recovery vSAN Storage Clusters
Administrators can now deploy a dedicated Cyber Recovery vSAN ESA Storage Cluster directly through the vCenter Quickstart workflow. These isolated environments are specifically designed to support disaster recovery and ransomware recovery scenarios.
The solution integrates with:
- VCF Protection and Recovery
- Health monitoring and security alerts
- Recovery validation workflows
This makes it easier than ever to establish a secure recovery environment capable of withstanding modern cyber threats.
On-Premises Clean Room Recovery
Organizations can now leverage integrated Clean Room Recovery workflows powered by vSAN snapshots.
Key capabilities include:
- Immutable recovery points
- Integrated Endpoint Detection and Response (EDR)
- vDefend-powered network isolation
- Automated recovery workflows
The result is faster recovery times and significantly reduced downtime during cybersecurity incidents.
Intelligent Replication Enhancements
Seeding for vSAN Replication
Data replication can often consume considerable bandwidth and time, particularly when replicating large datasets.
With Replication Seeding, vSAN can leverage pre-existing replica data and transfer only incremental changes instead of performing a full synchronization.
Advantages include:
- Faster initial synchronization
- Reduced WAN bandwidth consumption
- Accelerated disaster recovery setup
- Improved operational efficiency
Replication from Any Source Storage
Another major enhancement is the ability to replicate workloads from virtually any storage platform into a vSAN ESA target cluster.
This broadens the reach of vSAN replication services and allows organizations to benefit from:
- Dynamic protection groups
- Immutable snapshots
- Integrated vCenter management
- Unified disaster recovery operations
for workloads that may not currently reside on vSAN.
Simplified Protection Group Management
Tag-Based VM Membership
Managing protection groups manually becomes increasingly difficult as environments grow.
VCF 9.1 introduces Tag-Based VM Membership for vSAN Protection Groups. Administrators can automatically include VMs in protection policies based on assigned tags.
For example:
- Production
- Finance
- Tier-1
- SQL
- Mission Critical
As new virtual machines inherit the appropriate tags, protection is automatically applied without requiring administrative action.
This capability reduces management overhead while minimizing the risk of unprotected workloads.
Flexible Snapshot Retention Policies
Recovery requirements vary widely across organizations.
To address this, vSAN 9.1 now supports Multiple Snapshot Retention Schedules, allowing administrators to create:
- Daily snapshots
- Weekly snapshots
- Monthly snapshots
This flexibility enables organizations to meet both operational recovery objectives and long-term cyber recovery requirements using a single platform.
Improved Storage Efficiency
Storage efficiency receives a substantial boost in vSAN ESA.
Enhanced Compression
VCF 9.1 introduces further improvements to ESA compression algorithms, delivering better space savings while maintaining the performance characteristics for which ESA is known.
Organizations can expect:
- Reduced storage consumption
- Improved effective capacity
- Better ROI on storage investments
Global Deduplication
One of the most anticipated features in vSAN ESA is finally here: Global Deduplication.
Unlike traditional deduplication technologies, this implementation operates:
- Across the entire cluster
- As a post-process operation
- With encryption support
This allows organizations to maximize capacity efficiency while maintaining both security and performance.
Key Benefits
- Cluster-wide data reduction
- Improved usable capacity
- Data-at-rest encryption support
- Reduced storage costs
Advancements for Kubernetes and Cloud-Native Workloads
VCF 9.1 significantly enhances VMware's cloud-native storage capabilities.
RWX File Volume Support Expansion
Read-Write-Many (RWX) file volumes are now available for:
- VM Service VMs
- Multiple clusters within a single vSphere Zone
This allows modern applications to share storage more efficiently across Kubernetes and virtual machine-based workloads.
Fast Clone Volume Support
Fast Clone Volume support introduces:
- Rapid volume provisioning
- Snapshot-based cloning
- Shared disk support
- Non-disruptive VM migrations
- Storage policy updates through reprovisioning
These capabilities improve agility while reducing operational complexity.
Massive CNS/CSI Scalability Improvements
Container storage scalability continues to expand dramatically.
VCF 9.1 now supports:
- Up to 50,000 volumes per vCenter
- Shared-disk clustered workloads on Supervisor Clusters
- Unified Persistent Volume Claim monitoring through VCF Operations
This makes vSAN an increasingly attractive platform for large-scale Kubernetes deployments.
Better File Services Performance
File Services customers will appreciate the performance improvements delivered in this release.
Faster SMB Operations
vSAN File Services now provides up to:
2x faster metadata performance
for SMB-based workloads.
This is particularly beneficial for:
- User profile services
- Departmental file shares
- Home directories
- General enterprise file services
The improvement enhances responsiveness and overall user experience.
Expanded Support for Clustered Applications
Mission-critical clustered applications often present unique storage challenges.
VCF 9.1 expands support for clustered workloads and allows administrators to:
- Expand clustered disks online
- Avoid application downtime
- Support Oracle RAC multi-writer configurations
- Support Windows Server Failover Clusters (WSFC)
- Support shared VMDK architectures
This simplifies lifecycle management for some of the most demanding enterprise applications.
Disaggregated Storage and Multi-vCenter Flexibility
vSAN Stretched Storage Across vCenter Instances
Organizations operating multiple vCenter environments can now stretch storage resources across management boundaries.
Use cases include:
- Cross-workload domain storage sharing
- Multi-VCF deployment architectures
- Greater operational flexibility
- Improved infrastructure utilization
This capability represents a significant step toward truly disaggregated infrastructure architectures.
Shared vSAN Storage Cluster Support
VCF 9.1 expands storage sharing capabilities further by allowing:
- vSAN ESA clusters to be mounted remotely
- vSAN OSA clusters to be mounted remotely
- Compute-only clusters to consume shared storage services
This helps organizations separate compute and storage scaling strategies while reducing infrastructure overhead.
Comprehensive Security with End-to-End Encryption
Security remains a core focus.
VCF 9.1 introduces End-to-End Encryption for Disaggregated vSAN, providing:
- Client-to-storage cluster encryption
- Data-in-transit protection
- Data-at-rest protection
- Complete encryption coverage across storage communications
For organizations implementing disaggregated storage architectures, this delivers enterprise-grade security without additional complexity.
Simplified Stretched Cluster Maintenance
Managing maintenance windows in stretched-cluster environments has traditionally been challenging.
VCF 9.1 introduces Site Maintenance Mode for vSAN Stretched Clusters.
The feature allows administrators to:
- Place an entire site into maintenance mode
- Automate promotion of surviving sites
- Streamline planned maintenance operations
- Improve operational resilience during site-level events
This reduces complexity and risk when performing infrastructure upgrades or maintenance activities.
Final Thoughts
vSAN 9.1 in VMware Cloud Foundation 9.1 is much more than an incremental release. It represents a strategic evolution of the platform, bringing together enhanced cyber recovery capabilities, stronger data protection, improved storage efficiency, expanded cloud-native support, and greater operational flexibility.
The introduction of features such as Auto RAID-6, Global Deduplication, Cyber Recovery Clusters, Replication Seeding, End-to-End Encryption, and enhanced Kubernetes scalability demonstrates VMware's continued investment in making vSAN a comprehensive enterprise storage platform.
For organizations looking to strengthen resilience against cyber threats, improve storage efficiency, and modernize both traditional and cloud-native applications, vSAN 9.1 delivers a compelling set of capabilities that make upgrading well worth consideration.
