Software-Defined Storage: Guide to Top SDS Vendors

The software-defined storage (SDS) space keeps expanding, offering smarter ways to manage data across on-prem, cloud, and hybrid environments. Whether you’re running VMs, containers, or AI workloads, SDS promises flexible, scalable storage without the vendor lock-in of traditional SAN arrays.

Choosing the right SDS solution depends on your infrastructure, workload, and budget. Some systems zap complexity with single-pane management, others aim for deep ecosystem integration or performance at scale. Let’s explore SDS, compare today’s leading platforms, and help you find the best fit.

What Is Software-Defined Storage (SDS)?

Software-Defined Storage (SDS) is a storage architecture that separates software layer from the underlying hardware, enabling flexible, hardware-agnostic data management across virtualized, cloud, or traditional infrastructures.

For example, instead of deploying expensive, proprietary SAN or NAS systems, organizations can install SDS on standard x86 servers to create scalable, centralized storage pools. This allows them to expand capacity, manage storage from a single interface, and adapt quickly to changing workloads, without vendor lock-in or hardware overhauls. SDS is especially valuable for businesses modernizing their legacy disaggregated IT infrastructure, moving to hyperconverged systems, or integrating hybrid cloud environments.

Types of Software-Defined Storage

SDS comes in several architectures, each balancing performance, latency, throughput, and scale for different needs. From IOPS‑hungry, latency‑sensitive databases to cloud‑native object repositories, SDS covers a wide range thanks to modular software on standard hardware. Here’s a practical map.

Type	What it is	Typical workloads	Common interfaces / protocols
HCI / Virtual SAN (node‑local SDS)	Pools local disks across cluster nodes. Data services (mirroring/erasure coding) run on each host and present a datastore to the hypervisor. Some products also export external protocols.	General virtualized workloads, VDI, ROBO/edge, HA clusters, SAN replacement in small/medium footprints.	Hypervisor‑native datastores (e.g., VMFS/vVols, Cluster Shared Volumes). Some vendors optionally expose iSCSI, NFS/SMB, or NVMe‑oF.
Scale‑out block SDS (software SAN)	Disaggregated block storage built from commodity servers; storage nodes present shared block to separate compute.	Databases, virtualization with a separate compute layer, containers via CSI.	NVMe‑oF (TCP or RDMA), Fibre Channel, iSCSI.
Scale‑out / parallel file systems	Distributed namespace with parallel I/O across nodes for high throughput and horizontal scale.	Media production, AI/ML training, HPC, analytics, large backup/archive repositories.	POSIX (native client), often NFS and/or SMB gateways.
Object storage	Stores data as objects with metadata in a flat namespace; accessed over HTTP.	Cloud‑native apps, archives, backups, data lakes, media delivery.	S3‑compatible API, Swift API.
Cloud‑optimized / multicloud SDS	Adds policy‑based placement, caching, tiering, and replication across on‑prem and public cloud; often an overlay across other SDS types.	DR to cloud, cloud bursting, lifecycle tiering, cost optimization.	Varies by product: block (iSCSI/FC/NVMe‑oF), file (NFS/SMB), and/or object (S3).

Benefits of Software-Defined Storage

Software-Defined Storage (SDS) was a fundamental change in how organizations manage, scale, and optimize storage infrastructure. By decoupling storage services from proprietary hardware, SDS provides a set of benefits that directly address modern IT challenges.

Cost efficiency

One of the most immediate benefits of SDS is a significant reduction in capital (CapEx) and operational (OpEx) expenditures. Traditional storage solutions often rely on proprietary hardware, which drives up costs due to vendor lock-in, complex licensing models, and specialized support requirements. In contrast, SDS runs on commodity x86 servers, eliminating the need for expensive storage arrays. This allows organizations to repurpose existing hardware or select cost-effective configurations tailored to their needs.

Flexibility and compatibility

SDS platforms are designed to be hardware-agnostic and hypervisor-neutral. They support a wide range of protocols (iSCSI, SMB, NFS, S3) and integrate seamlessly with virtualization platforms such as VMware vSphere, Microsoft Hyper-V, and KVM. This flexibility allows organizations to build hybrid environments, combine different storage media (HDDs, SSDs, NVMe), and scale resources as needed, without being tied to a specific vendor’s roadmap or ecosystem.

As a result, SDS simplifies procurement and deployment across diverse infrastructure stacks, whether on-premises, in the cloud, or at the edge.

Simplified management

SDS consolidates storage operations into a unified management layer with centralized control, often accessible through a web-based or API-driven interface. Advanced features such as policy-based provisioning, automation, deduplication, compression, snapshots, and replication are typically included out-of-the-box. This reduces the administrative burden on IT teams by eliminating manual configuration steps and enabling faster response to changing workload demands.

Scalability

Traditional storage systems are limited by scale-up architecture, which requires forklift upgrades and downtime to expand capacity or performance. SDS, on the other hand, follows a scale-out model: additional capacity or performance is achieved by simply adding new nodes to the cluster.

This linear scalability ensures that storage infrastructure can grow in step with business needs, without disruption. Whether the workload involves a few virtual machines or a distributed application spanning multiple data centers, SDS provides predictable and incremental growth.

Data protection and availability

Most SDS solutions come with built-in mechanisms for data redundancy, high availability, replication, and disaster recovery. These features are typically software-defined and do not require dedicated hardware or third-party solutions. Data can be mirrored across nodes or sites to ensure availability in the event of hardware failure or site outage.

Common use cases

SDS is most used in scenarios such as:

Use Case	Description	Why SDS?
Virtualization infrastructure	Shared storage for virtual machines across platforms like VMware, Hyper-V, and KVM.	Separates storage from hardware, enables fast provisioning, supports automation.
Hyperconverged infrastructure (HCI)	Combines compute, storage, and networking into a single software-managed appliance.	Simplifies deployment, reduces hardware footprint, enables linear scalability.
High availability (HA) and disaster recovery (DR)	Ensures business continuity via data replication across servers within single location or across multiple sites.	Integrated replication and failover, hardware flexibility, improved RTO/RPO.
Remote and branch offices (ROBO)	Centralized storage management for geographically distributed sites.	Lightweight deployment, minimal on-site IT requirements, remote provisioning.
Backup and archiving	Provides reliable, scalable storage for long-term retention and data protection.	Cost-effective capacity scaling, support for deduplication and compression.
Development and testing	Delivers agile storage environments for CI/CD pipelines and sandbox testing.	Rapid provisioning, cloning, snapshot support, API integration.
Big data and analytics	Supports data lakes, AI/ML workloads, and analytics platforms requiring high throughput and scalability.	Scale-out design, parallel data access, compatibility with mixed media (HDD, SSD, NVMe).
Containerized workloads	Persistent storage for Kubernetes and other container orchestration systems.	CSI compatibility, dynamic provisioning, multi-tenant isolation.
Hybrid and multi-cloud deployments	Bridges on-premises infrastructure with public cloud platforms.	Unified storage plane, cross-environment replication, no vendor lock-in.

What do you need to run SDS?

To implement Software-Defined Storage, you don’t need proprietary hardware, but several key components are required:

• x86-based servers: сommodity hardware such as x86-based servers with sufficient CPU, RAM, storage, and networking resources to handle SDS workloads.
• Supported OS or hypervisor: Linux, Windows Server, or VMware ESXi, depending on the chosen SDS vendor.
• High-speed switches: ensure low-latency, high-throughput communication within the infrastructure.
• SDS software stack: includes centralized console for storage provisioning, automation, monitoring, and access control.
• API & orchestration support: REST APIs or integrations with tools like Kubernetes, Ansible, or vCenter for automation and scalability. These are mostly needed for large-scale deployments and are optional for small environments.

Top Software-Defined Storage vendors in 2025

The Software-Defined Storage market continues to evolve rapidly in 2025, with vendors offering solutions tailored to different IT environments. Below are some of the top SDS vendors.

VMware vSAN

Overview:

VMware vSAN remains a leading SDS solution, tightly integrated into the VMware ecosystem. Included directly into the ESXi hypervisor, vSAN aggregates local disks across a cluster to form a shared storage pool managed via vCenter. It offers policy-based storage provisioning, native data protection, and supports stretched clusters for high availability. VMware Cloud Foundation (VCF) further extends vSAN capabilities in hybrid cloud deployments.

VMware vSAN Operations Overview dashboard

Key Features:
 

• Deep integration with VMware stack (vSphere, NSX, Tanzu, Horizon)
• Storage policies for performance, availability, and compliance
• Native support for disaster recovery, deduplication, and compression
• Scales easily with additional hosts

Best for:


Enterprises already invested in VMware technologies looking for seamless SDS integration with virtualization and cloud infrastructure.

Considerations: 

• VMware vSAN Hardware Compatibility: VMware provides a hardware compatibility matrix that lists server hardware certified to work with vSAN. It’s critical to verify that your servers, network components, and storage devices are on the list to ensure stable performance and full support.
• Licensing: requires VMware vSAN included license.
• Limited hypervisor flexibility (ESXi only).

Microsoft Storage Spaces Direct (S2D)

Overview:

Storage Spaces Direct is Microsoft’s SDS solution built into Windows Server Datacenter edition. It uses local disks in a Windows Server cluster to create highly available, scalable storage and is a core component of Azure Stack HCI. S2D management experience can be further improved with tools like Windows Admin Center or System Center.

S2D Storage Pools overview in Windows Server Manager

Key Features: 

• Native to Windows Server and Azure Stack HCI
• Compatible with industry-standard x86 hardware
• Integrated with Active Directory, PowerShell, and Windows Admin Center
• Supports SMB3, caching, and storage tiers
• Delivers both converged and hyperconverged deployments

 Best for: 

SMBs and enterprises using Windows Server and Azure who want tight integration and cost-effective SDS.

Considerations: 

• Hardware compatibility: S2D requires certified hardware. While most modern server components are supported, this requirement limits flexibility in choosing hardware.
• Licensing: S2D is only available with Windows Server Datacenter edition.
• Limited native support for Linux and Kubernetes: S2D runs only on Windows Server hosts. While Linux VMs can be deployed, the platform lacks native integration with Linux-based management tools. Kubernetes is not built-in and must be deployed and managed separately.
• Basic built-in management tools: Native S2D management interfaces may feel outdated compared to other SDS platforms. This can be improved with Windows Admin Center or System Center, but these require additional system resources, and System Center comes with extra licensing costs.

StarWind Virtual SAN (VSAN)

Overview:

StarWind VSAN is a high-performance SDS solution designed for SMB, ROBO, and edge use cases. It runs on standard x86 servers and creates a fault-tolerant, shared storage pool from local disks. Unlike many SDS vendors, StarWind does not require a separate witness node and can run as a VM or bare-metal service, which simplifies deployment in small environments.

Create LUN wizard in StarWind Virtual SAN web UI

Key Features: 

• Ease to deploy and manage, centralized management web UI, minimal learning curve
• Supports iSCSI, NVMe-oF, NFS and SMB protocols
• High availability and most storage features are available starting from 2 nodes
• Compatible with commodity x86 hardware, no strict HCLs
• Supports Microsoft Hyper-V, VMware ESXi, Proxmox VE, and other KVMs
• Lightweigh and robust software architecture provides maximum performance with minimum overhead

Best for:

SMBs, ROBO, and edge sites that need compact, cost-effective, and easy to manage SDS

 Considerations: 

• Focused on operational simplicity over large-scale orchestration.

Nutanix Unified Storage

Overview: 

Originally known for hyperconverged infrastructure, Nutanix has expanded its SDS portfolio with Nutanix Unified Storage (NUS). It separates storage from compute and offers file, block, and object services. NUS is managed via Nutanix Prism and integrates tightly with the Nutanix Cloud Platform (AOS), supporting multi-cloud and hybrid environments.

Nutanix Prism home screen

Key Features:
 

• Unified file, block, and object storage in one platform
• Built-in replication, snapshots, and disaster recovery
• Intelligent tiering and machine learning-based optimization
• Managed via Nutanix Prism or REST APIs
• Native integration with Nutanix AHV and Kubernetes

Best for: 

Organizations already invested in Nutanix infrastructure or looking for unified SDS with strong multi-cloud capabilities.

Considerations: 

• Hypervisor limitation: usage is limited to the Nutanix AHV hypervisor, reducing flexibility compared to solutions that support multiple hypervisors.
• Hardware compatibility: Nutanix AHV requires certified hardware, which limits the range of server platforms that can be used with NUS.
• Licensing: Licensing may be complex depending on deployment model.

Red Hat Ceph Storage

Overview: 

Red Hat Ceph is an open-source, massively scalable SDS solution built on the Ceph project. Designed for cloud-native, containerized, and AI/ML workloads, it integrates tightly with Red Hat OpenShift and OpenStack environments.

Ceph installer wizard in RHEL

Key Features: 

• Highly scalable, distributed architecture
• Supports S3-compatible object storage, RBD (block), and CephFS (file)
• Deep integration with Kubernetes and OpenShift
• Strong performance for AI/ML and big data
• Fully open-source with commercial support from Red Hat

Best for: 

Cloud-native applications, service providers, and enterprises needing flexible, scalable, and open-source SDS.

Considerations:

• Requires significant Linux expertise.
• Platform limitation: Ceph is available with Proxmox VE, Red Hat OpenStack Services on OpenShift, but is not supported in standalone Red Hat KVM deployments. It has been also tested on Ubuntu and CentOS and available in Proxmox VE.
• Operational complexity at scale, steep learning curve for small teams.

DataCore SANsymphony

Overview: 

DataCore SANsymphony is a mature SDS platform designed to virtualize and manage storage across heterogeneous environments. It supports SAN, NAS, DAS, and local server disks, enabling both traditional and HCI configurations. The platform offers features like caching, auto-tiering, and synchronous mirroring.

DataCore SANsymphony user interface

Key Features: 

• Hardware-agnostic storage virtualization
• Features deduplication, caching and automated storage tiering
• Offers synchronous and asynchronous replication for HA and DR
• Provides centralized management and analytics
• Integrates with VMware vSphere, Microsoft Hyper-V, and Linux KVM

Best for:

Enterprises with diverse storage environments that need a flexible SDS layer compatible with both modern and existing infrastructure.

Considerations: 

• May require training for full feature use.

NetApp ONTAP Select

Overview: 

ONTAP Select brings NetApp’s flagship ONTAP software to industry-standard x86 servers. It delivers enterprise-grade NAS and SAN features as SDS, enabling flexible deployments in edge, ROBO, or virtualized data centers. It also integrates with NetApp’s hybrid cloud ecosystem.

NetApp ONTAP user interface

Key Features: 

• Proven ONTAP software stack on commodity hardware
• SnapMirror replication, deduplication, and compression
• S3-compatible object support
• Centralized management via NetApp Cloud Manager
• Supports single- or multi-node deployments placed on-prem or in the cloud

Best for:

Enterprises seeking to replicate ONTAP functionality outside traditional NetApp appliances or extend it to edge and virtualized deployments.

Considerations: 

• Best when paired with other NetApp products.
• Licensing tied to capacity and performance tiers.
• Limited hypervisor flexibility: available only for KVM and VMware hypervisors.
• CPU architecture restriction: supported only on Intel-based servers; AMD processors are not supported.

IBM Spectrum Scale

Overview: 

IBM Spectrum Scale (formerly GPFS) is a high-performance SDS solution designed for demanding workloads like HPC, AI, and analytics. It offers scalable, POSIX-compliant file services with advanced caching, multi-site replication, and policy-driven data placement.

IBM Spectrum Scale Services UI

Key Features: 

• Parallel file system optimized for performance
• Supports hybrid cloud and multicloud deployments
• Tiering to tape, cloud, and local disk
• Multi-protocol access (POSIX, NFS, SMB, HDFS, S3)
• Advanced metadata and lifecycle management

Best for: 

Research institutions, AI/ML workloads, and enterprises needing fast parallel access to massive datasets.

Considerations: 

• Requires advanced administration skills.
• Overkill for general-purpose use cases.

OpenEBS (for Kubernetes environments)

Overview: 

OpenEBS is a Kubernetes-native SDS solution that provides persistent block storage for containerized workloads. It runs per-pod and supports multiple storage engines like cStor and Mayastor, enabling performance tuning for stateful applications.

OpenEBS Storage Classes overview

Key Features: 

• Fully containerized storage for Kubernetes
• Dynamic volume provisioning with CSI
• Multiple backends (local PV, NVMe, iSCSI, etc.)
• Cloud-native monitoring and automation
• Open-source with commercial support via MayaData

Best for: 

DevOps teams running Kubernetes clusters that need lightweight, customizable SDS for cloud-native apps.

Considerations: 

• Not suited for non-Kubernetes environments.
• Performance varies based on selected engine and configuration.

SDS Vendors Summary

Final Thoughts

There’s no one-size-fits-all Software-Defined Storage solution in 2025. It all depends on your environment, team expertise, and growth plans.

• VMware vSAN excels in VMware-centric enterprises.
• Microsoft Storage Spaces Direct (S2D) fits Azure and Windows environments tightly.
• StarWind Virtual SAN is ideal for SMBs and remote offices needing simplicity and cost efficiency.
• Nutanix Unified Storage offers easy scaling and hybrid cloud readiness.
• Red Hat Ceph Storage is a solid open-source choice for cloud-native and containerized workloads.
• DataCore SANsymphony is great for replacing legacy SAN/NAS with versatile protocol support.
• NetApp ONTAP Select stands out in hybrid cloud and enterprise data management.
• IBM Spectrum Scale and Pure Storage Purity focus on high-performance, demanding workloads.
• OpenEBS is essential for Kubernetes environments needing container-level storage control.

Pick your SDS platform based on infrastructure compatibility, licensing model, and support model. A well-matched solution will not only reduce storage costs but also streamline operations across your stack in 2025 and beyond.

 

Vendor	Primary Focus	Licensing Model	Key Strengths	Best For
VMware vSAN	VMware ecosystem, enterprise	Subscription	Tight VMware integration, mature	Large VMware shops, enterprises
Microsoft Storage Spaces Direct (S2D)	Azure integration, Windows shops	Perpetual & Subscription	Seamless Windows/ Azure integration	Azure-centric, Windows environments
StarWind Virtual SAN (VSAN)	SMB, ROBO, edge	Perpetual & Subscription	Cost-effective, simple, flexible	SMB, remote offices
Nutanix Unified Storage	HCI, hybrid cloud	Subscription	Easy scale, multi-cloud ready	Enterprises, cloud-hybrid
Red Hat Ceph Storage	Open source, cloud-native	Subscription	Open source, container-native	Cloud-native, Linux environments
DataCore SANsymphony	SAN/NAS replacement, multi-protocol	Subscription	Protocol flexibility, legacy support	Enterprise SAN replacement
NetApp ONTAP Select	Hybrid cloud, enterprise	Subscription	Strong data management, cloud	Enterprise, hybrid environments
IBM Spectrum Scale	High performance, AI workloads	Subscription	Performance, AI/data analytics	High-end, AI-driven workloads
OpenEBS	Kubernetes-native SDS	Open source	Cloud-native, container-granular storage	Kubernetes environments, DevOps

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