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Software-Defined Storage

A Comprehensive Guide to Enterprise Software-Defined Storage Technology

This guide is intended to be educational and present a high-level overview of software-defined storage for on-premises/private, public, edge, and hybrid clouds. For a more technical description go to our product page: Lightbits software-defined storage.

What is Software-defined Storage?

Software-defined storage (SDS) technology is an approach to data storage architecture in which the software that manages storage-related tasks is decoupled from the physical storage hardware. SDS architecture enables storage provisioning, management, and optimization through software, abstracting the hardware.

Software-defined storage is used primarily in data centers due to the need for storage consolidation, scalability, cost efficiency, flexibility, and centralized management. SDS helps modernize data center operations, making it a crucial component in meeting the evolving storage demands of today’s digital enterprises. 

SDS can also be provisioned through service providers–cloud service providers, the AWS Marketplace, the Microsoft Azure Marketplace, and specialty service providers, such as AI Cloud service providers like Crusoe Cloud.

SDS in the Data Center

SDS can integrate seamlessly with your existing data center infrastructure and transform how your storage is managed and utilized, providing a more flexible, scalable, and cost-effective solution compared to traditional storage architectures. By decoupling the storage management from the hardware, you can optimize your storage resources, enhance performance, and better align with the dynamic needs of a modern IT environment.

SDS vs. Traditional Storage. The primary difference between SDS software-defined storage and traditional storage lies in how the storage infrastructure is managed and implemented. SDS offers a more flexible, scalable, and cost-efficient approach compared to traditional storage. SDS leverages commodity hardware and centralized management, providing greater adaptability to modern IT environments and integration with cloud services. Traditional storage, while reliable and often optimized for specific use cases, tends to be more expensive, less flexible, and more challenging to scale and manage due to its reliance on proprietary hardware and fragmented management tools. In these architectures, the hardware and software are tightly integrated, with the storage management functions tied to specific hardware devices.

How SDS is different from NAS and SAN. SAN (Storage-Attached Network) and NAS (Network-Attached Storage) are types of traditional storage architectures designed for specific workloads, offering robust solutions for block-level and file-level storage, respectively. While they provide reliable and performant storage options, they are often deployed in a fixed configuration and not easily reconfigurable; resulting in flexibility, scalability, and cost limitations. In contrast, software-defined storage represents a modern approach that leverages commodity hardware and centralized management to offer more adaptable and cost-effective storage solutions. 

SDS can be deployed on a SAN or NAS, allowing you to optimize your existing infrastructure, increase flexibility, and improve storage efficiency. However, successful integration will require careful consideration of compatibility and potential complexities. 

Software-defined Storage vs. Cloud Storage

Both SDS and cloud storage offer modern, flexible solutions for data storage, however, can be implemented to meet different needs. SDS is best for organizations that require control over their storage infrastructure and are willing to manage it within their data centers. On the other hand, cloud storage is ideal for businesses that prioritize leveraging the infrastructure and services of third-party cloud providers. It’s important to understand that SDS can be provisioned through cloud service providers as well and in either case offer the benefits of scalability, accessibility, and reduced management complexity.

Integrating software-defined storage with cloud services

SDS can be effectively integrated with cloud services, providing a seamless and flexible hybrid storage environment that leverages the strengths of both on-premises and public cloud storage. This approach allows you to leverage the performance and control of on-premises SDS while benefiting from the scalability and flexibility of public cloud storage. This integration can be achieved through cloud gateways and unified management tools. The result is a scalable, cost-efficient, and flexible storage solution that enhances data management, protection, and overall operational efficiency and agility. 

The Cloud Gateway acts as a bridge between on-premises SDS and cloud storage transferring data between the local SDS infrastructure and cloud storage services. Most organizations choosing this implementation model will benefit from a unified management control plane that supports hybrid environments, providing a centralized interface to control storage policies, provisioning, and monitoring of both the on-premises and cloud storage resources.

Many organizations leverage a hybrid implementation model for its flexibility in data tiering, automatically moving data to where and when it’s needed while optimizing costs–frequently accessed data on-premises and infrequently accessed data on the cloud. Other organizations will choose a hybrid model to satisfy backup and disaster recovery (DR) strategies. While others need to respond to unpredictable storage capacity demands and will temporarily move workloads or data to the cloud when on-premises resources are not sufficient–a practice referred to as “cloud bursting”. For any of these use cases, SDS offers the flexibility to deliver a similar experience while adapting to the environment. 

Types of Software-Defined Storage (SDS)

SDS encompasses a range of technologies with numerous software-defined storage vendors catering to different aspects of enterprise storage needs, from large-scale object storage to integrated Hyper-converged Infrastructure (HCI) platforms.

Types of Software-Defined StorageDescriptionExamples of Commercial Software-defined Storage Companies
Scale-out blockSDS for block storage supports iSCSI, Fibre Channel, and Ethernet protocols and clusters server nodes into a single system resulting in coherent communication between nodes. Lightbits high-performance, software-defined block storage
Scale-out fileA distributed, unified file system that spans across all nodes in the cluster, providing a single namespace for storing and accessing files supporting NFS, SMB/CIFS, iSCSI, InfiniBand, and object storage API protocols.NetApp ONTAP, Pure Storage FlashBlade, WekaIO
Scale-out block and fileThis type of SDS supports block (iSCSI and Fibre Channel) and file (NFS, SMB, InfiniBand) storage protocols, making it suitable for various applications and workloads.Dell EMC PowerFlex, IBM Spectrum Scale, NetApp ONTAP, Qumulo
Scale-out objectSoftware-defined object storage distributes data across multiple nodes in a flat namespace, assigning unique identifiers and metadata to the objects themselves Cloudian HyperStore, MinIO, Scality RING, SwiftStack
Unified block, file, and object storageUnified storage supports multiple protocols but tends to prioritize one or two, while unifying storage management across a distributed server clusterDell EMC PowerScale (Isilon), HPE, IBM Ceph Storage, SUSE Enterprise Storage
HCI & Storage VirtualizationA fully integrated infrastructure system that consolidates compute, storage, and networking into a virtualized pool of resources or that can be managed as a cluster of appliances typically through a single management console. HPE SimpliVity, VMware vSphere and vSAN, Nutanix, Cisco HyperFlex, Dell EMC VxRail, DataCore SANsymphony, NexentaStor

 

What is free Software-Defined Storage?

Free SDS solutions provide many of the features of commercial software-defined storage solutions, such as scalability, centralized management, and hardware agnosticism, but do so without licensing fees. Most of these solutions are open-source software-defined storage, allowing users to access, modify, and distribute the source code. Examples include SwiftStack, Ceph Storage, GlusterFS, NexentaStor, OpenEBS, MinIO, and FreeNAS. There may be considerations around support and complexity, as most rely primarily on community support, which can vary in responsiveness and depth, they may require more technical expertise to deploy and manage, and while robust, free SDS solutions may lack some of the advanced features found in commercial products.

Continue your learning: Building Data Storage for the Future 

How does software-defined storage work?

SDS does not separate the storage itself from the hardware; it abstracts storage resources from the hardware. It is a software controller that virtualizes and manages your physical storage resources; sitting between the physical storage and data requests managing how and where data is stored. SDS consolidates all storage capacity and creates a unified, centrally managed storage pool providing access services, networking, and connectivity for all your applications without assuming anything about the underlying hardware’s capabilities. And because it operates through an abstraction layer, a control plane, it can dynamically pool storage resources via policy-based management and automated provisioning. 

The SDS model has gained prominence and adoption due to its inherent flexibility, its hardware independence eliminates reliance on proprietary infrastructure, allowing you to choose any hardware vendor that meets your needs, and avoiding vendor lock-in. It’s an attractive architecture model because it maximizes storage capabilities while minimizing administrative overhead by automating and orchestrating storage management on top of private or public clouds. With this model, storage can be scaled up or scaled out with minimal disruption to operational procedures and reduced capital investment. 

Architecture

SDS is architected to abstract storage resources from physical hardware, creating a flexible, scalable, and centrally managed storage environment. Each core architecture component would be present in the implementation across various solution software-defined storage vendors. Here is a list of key components of software-defined storage architecture

Abstraction Layer: The core component that decouples the storage services from the physical hardware itself and makes virtual storage pools appear as a single storage pool to applications and users.

Control Plane: The centralized management layer for storage operations ensuring efficient resource utilization by orchestrating and automating storage tasks: provisioning, monitoring, policy enforcement, and metadata.

Data Plane: The layer that manages actual data storage and retrieval by executing read/write operations and essential data services (replication, deduplication, compression). It ensures data integrity and high performance during data access.

Lightbits Data Platform software-defined storage topology with applications

Example of Lightbits Data Platform software-defined storage topology

Management Interface: The tool used to interact with the SDS system for visibility and control over the storage infrastructure which in most cases can provide a dashboard for configuring, monitoring, managing storage resources, and simplifying administrative tasks.

 

What do you need to run software-defined storage?

The SDS model is an effective solution for modern data storage needs. With these components and considerations, you can effectively deploy and manage an SDS environment, benefiting from its flexibility, scalability, and cost efficiency. 

  • Storage Nodes: physical or virtual servers that contribute storage resources. Each node runs on the SDS software, which abstracts its storage resources and adds them to the centralized pool. These can be commodity or proprietary servers, as long as there is adequate CPU, memory, and storage capacity. Software-defined storage vendor solutions will vary on the storage media implemented which can include SSDs, HDDs, or NVMe drives. You should implement the solution that delivers the performance and capacity requirements that your applications require.
  • Network Fabric: The high-speed, low latency Network Interface Cards (NICs) and network technologies that connect, facilitate node communication, and ensure data can be transferred efficiently across the cluster. When choosing which networking option to employ, consider the performance and latency requirements of your applications, networking technology options can vary from iSCSI, Fibre Channel, InfiniBand, NFS, and NVMe over TCP. 
    • While traditionally SDS is associated with networked storage solutions like NAS and SAN, it can also be implemented in a Direct Attached Storage (DAS) architecture. In a DAS implementation, the storage devices are directly connected to a single computer or server without a network in between.
  • Cluster Management: Aggregating storage resources by clustering the storage nodes and managing them as a single entity has many technological and operational advantages, such as high availability, redundancy, scalability, and simplified administration. If one node fails, others can take over its workload to maintain continuous service. The DAS model is not a clustered architecture. 
  • SDS Software: Finally, there’s the SDS layer running on each storage node managing the storage abstraction, resource pooling, policy enforcement, and data services.

Continue your learning: The Ultimate Software-Defined Storage Glossary 

What are the disadvantages and advantages of software-defined storage?

Overall, while SDS offers significant benefits in terms of flexibility, efficiency, and modernization, it also comes with challenges that need to be carefully considered to fully realize its potential. It can be difficult to generalize the advantages and disadvantages which ultimately, are going to be intimately connected to your choice of software-defined storage vendor and the implementation model. That said, frequently cited advantages of SDS include flexibility, scalability, cost efficiency, centralized management, [automation of] essential data services, high performance, improved resource utilization, enhanced data protection, and hardware agnosticism. The disadvantages can include complexity, integration challenges, initial setup costs, varying vendor support, security concerns, resource requirements, and reliability.

DAS, in particular, is commonly a challenging implementation model at scale (in large environments) where complexity, scalability, and setup costs can impede a successful implementation.

Why do businesses choose a software-defined storage platform?

The advantages of SDS enable businesses to manage their storage more effectively, reduce costs, scale operations seamlessly, and ensure robust data protection and compliance. As a result, SDS is a powerful solution for modern data storage needs, offering significant strategic and operational benefits.

 

Benefit triangle of implementing Lightbits software-defined storage

The benefits of implementing the Lightbits high-performance software-defined storage platform

The primary reasons why businesses opt to implement SDS:

  • Flexibility: You can choose any hardware or platform (on-premises or public cloud) to fit your needs and budget, switch vendors easily, and avoid being tied to expensive proprietary solutions.
  • Cost-Efficiency: significantly reduces capital expenditures, reduces reliance on specific vendors, and lowers TCO
  • Scalability: scales up and out easily without significant reconfiguration or downtime, and provides a future-proof solution that grows with your business
  • Improved Resource Utilization: dynamically allocates storage resources based on application needs maximizing the use of available storage capacity, and improving overall efficiency
  • Automation: supports policy-based management and automated provisioning of storage resources reducing administrative overhead and accelerating deployments, and improves operational efficiency, leading to faster time-to-market for new applications and services.
  • Hybrid and Multi-Cloud Environments: SDS seamlessly integrates across on-premises and public cloud platforms. With solutions like the Lightbits data platform the software license is portable to whichever cloud (on-premises, public, or edge) the data resides

Why switch to Software-defined storage?

Companies switch to SDS primarily to maximize and extract the greatest utility from their storage investments. Due to its cost efficiency, scalability flexibility, and centralized management with automation capabilities, SDS delivers significant ROI. The benefits of software-defined storage enable you to reduce costs, easily scale your storage infrastructure, and simplify storage management.

Cost Efficiency: Because SDS enables the use of commodity hardware it can significantly reduce both CapEx and OpEx. By leveraging industry-standard servers and storage devices, companies can avoid the high costs associated with traditional storage hardware. Additionally, the ability to scale storage incrementally as needed helps avoid over-provisioning and reduces wasteful spending on unused capacity.

Scalability and Flexibility: With SDS you can add storage capacity incrementally by adding more nodes, which can be done without significant reconfiguration or downtime. This ensures that storage resources can quickly adapt to changing business needs, such as increasing data volumes or fluctuating workloads. The flexibility in platform and hardware models allows you to architect your infrastructure to meet the needs of specific application performance and capacity requirements.

Centralized Management and Automation: While centralized management is a key feature of SDS and offers significant benefits in terms of efficiency, consistency, and visibility, it is not a strict requirement and can be implemented with varying degrees of centralization. However, leveraging centralized management typically enhances the overall effectiveness and value of SDS, making it a preferred approach in many cases. Centralized management and automation can reduce the complexity of managing multiple storage systems and improve operational efficiency. Centralized management tools provide a single interface for monitoring and controlling storage resources, making it easier to enforce policies and optimize resource utilization. Automation capabilities further enhance efficiency by reducing manual intervention, speeding up deployment, and ensuring consistent application of policies across the storage infrastructure.

Continue your learning: Deploying Reliable High-Performance Storage with Lightbits 

Software-Defined Storage Drivers and Use Cases

Flexibility is often cited as the primary need driving the adoption of software-defined storage. It allows organizations to adapt to changing requirements, scale resources efficiently, manage diverse workloads, integrate with cloud services, and achieve cost savings—all while maintaining control and simplicity of storage management. This flexibility makes SDS a crucial component of modern IT infrastructure, supporting the dynamic and evolving needs of today’s digital enterprises.

Given the versatility and flexibility of SDS, the use cases for many data centers span many scenarios and meet many different business needs. 

Data Center Modernization: replaces legacy storage systems enabling better resource utilization and easier management

Hybrid and Multi-Cloud Deployments: enables seamless data movement between on-premises and cloud environments, providing cloud bursting, disaster recovery, and data archiving while optimizing costs and performance

Big Data and Analytics: offers a scalable solution that can handle the vast amounts of data generated by big data applications, like Elasticsearch, ensuring high performance and efficient data processing

DevOps and Agile Development: provides fast, flexible, and automated storage provisioning for development and testing environments, speeding up development cycles and improving collaboration between development and operations teams

Database and Transactional Workloads: offers scalable storage solutions optimized for the performance and reliability requirements of database and transactional workloads

Edge Computing: provides distributed storage capabilities that can operate efficiently in remote or edge locations, supporting real-time data processing and analysis closer to the source of data generation

Continue your learning: Transforming Big Data Analytics with Lightbits Software-Defined Storage

Software-defined storage trends

Given the undeniable technological and operational benefits of SDS, it will undoubtedly continue to see widespread adoption. The long-term trends for SDS point towards increased implementations in hybrid and multi-cloud environments, Software-Defined Everything (SDx), integration with AI/ML, and increased integration with containers and Kubernetes orchestration environments. 

SDS is integral to the adoption of hybrid and multi-cloud environments due to its ability to provide unified management, seamless data mobility, policy-based automation, and cloud cost optimizations. By abstracting storage management from the underlying hardware or cloud provider platform, SDS enables you to leverage the best of both on-premises and cloud storage, fostering a more agile and resilient IT environment.

Continue your learning: An Introduction to Azure Cloud Storage with Use Cases 

SDx is transforming how IT infrastructure is designed, deployed, and managed. By abstracting compute, storage, and networking resources into software layers, SDx provides unprecedented flexibility, scalability, and efficiency. Despite challenges like interoperability, the benefits of SDx—such as cost efficiency, centralized management, and improved security—make it a compelling approach for modernizing IT environments. As technologies like AI, edge computing, and 5G continue to evolve, SDx will play a crucial role in enabling the next generation of digital services and innovations.

Continue your learning: 4 Predictions of Cloud Storage Trends 

SDS can accelerate AI/ML data pipelines providing the high-speed storage required for quick data ingestion and preprocessing. And because it scales effortlessly, it can accommodate a fast-growing dataset while ensuring consistent and reliable data access for training and inferencing, seamless data mobility, and unified management of diverse data types. This makes SDS a critical component in modern AI/ML infrastructure, driving faster insights and innovations.

Continue your learning: The Rise of High-Performance Cloud Storage for AI 

SDS supports and enhances the use of Kubernetes. It can provide persistent storage ensuring that Kubernetes can effectively manage stateful applications large-scale deployments. Its compatibility with hybrid and multi-cloud environments is in line with the Kubernetes portability model, further enhancing its value, and making SDS a key enabler for modern, containerized applications.

Continue your learning: Persistent Storage for Containers 

Additional Resources