The scale and demands of unstructured data continue to grow at a relentless rate, making the need for optimized file-based data storage, and its simplified management, more crucial than ever.

OneFS secure snapshots help customers maximize the long-term value of their critical business data and drive down storage management cost and complexity. This simple, scalable solution offers fast, space-efficient, consistent copies of large datasets on Dell PowerScale NAS storage.

This white paper presents information for managing secure snapshots in a Dell PowerScale cluster. This document does not intend to provide a comprehensive background to the OneFS architecture.

See the OneFS Technical Overview white paper for further details about the OneFS architecture.

The target audience for this white paper is anyone configuring and managing secure snapshots within a OneFS-powered clustered storage environment. It is assumed that the reader has an understanding and working knowledge of the OneFS components, architecture, commands, and features.

More information about OneFS commands and feature configuration is available in the OneFS Administration Guide.

Dell Technologies and the authors of this document welcome your feedback on this document. Contact the Dell Technologies team by email.

Dell PowerScale OneFS is the operating system that powers the Dell PowerScale family of scale-out NAS storage solutions. Designed to handle large-scale unstructured data with high performance, efficiency, and security, OneFS provides a unified, scalable file system that integrates data protection, eliminates volume management, and supports multiple protocols and workloads across edge, core, and cloud environments.

OneFS 9.15 introduces support for the PowerScale Exascale Storage Platform — Dell's first software-defined, subscription-licensed PowerScale product. Rather than shipping as a fixed appliance, the Exascale platform decouples hardware and software: the Dell PowerEdge R7725xd server is procured through standard server sales channels, and OneFS (or ObjectScale) is licensed separately as a subscription. This model gives large AI and HPC customers access to the latest server generation significantly faster than traditional appliance refresh cycles allow.

The PowerEdge R7725xd is the first AMD-based node in the PowerScale lineup. It pairs dual AMD EPYC SP5 9455 processors (96 cores per node) with 768 GB of DDR5-6400 memory, 24 PCIe Gen5 NVMe U.2 SSDs, and 400GbE front- and back-end networking. Per-node raw capacity ranges from 184 TB (24 × 7.68 TB TLC) to 2.88 PB (24 × 122 TB QLC), and sequential throughput reaches 21 GB/s read and 12.4 GB/s write per node.

The Dell PowerScale portfolio is a family of scale-out NAS storage solutions built to handle any type of unstructured data — files, images, video, instrumentation data, and AI training datasets. PowerScale combines the performance, flexibility, and efficiency of the OneFS operating system with hardware innovations including all-NVMe, all-flash, hybrid, and archive nodes. PowerScale enables customers to run diverse workloads across multiple protocols, clouds, and locations while ensuring data security, protection, and management at scale.

The current PowerScale all-flash portfolio spans a range of performance, density, and cost points:

• PowerScale F910: The densest all-flash appliance node. 2U, dual-socket Intel Sapphire Rapids, 24 NVMe SSDs, up to 1.47 PB raw per node, 100GbE front and backend.
• PowerScale F710: Mid-range all-NVMe node. 1U, dual-socket Intel Sapphire Rapids, 10 NVMe SSDs, up to 610 TB raw per node.
• PowerScale F210: Entry all-NVMe node. 1U, single-socket Intel Sapphire Rapids, 4 NVMe SSDs, up to 61 TB raw per node.

OneFS 9.15 extends this portfolio with the Exascale Storage Platform, a software-defined offering built on the Dell PowerEdge R7725xd.

The R7725xd raises the performance ceiling significantly, quadrupling backend network bandwidth to 400GbE, and introducing the AMD EPYC SP5 processor — a first for PowerScale.

The Exascale platform is designed for large, strategic AI and HPC accounts that require extreme-scale storage: organizations training large language models, running distributed inference at scale, processing genomics or financial market data, and operating multi-petabyte media pipelines. Minimum deployments start at 10 PB and scale to 61 PB or more per rack.

• AI/ML Training: High-throughput sequential reads to feed GPU clusters during model training. The R7725xd's 400GbE connectivity and PCIe Gen5 drives deliver sustained data rates that can feed 16,000+ GPUs.
• HPC and Simulation: Parallel file system access patterns requiring both large sequential bandwidth and low-latency metadata operations at scale.
• AI Inference and RAG: Mixed random and sequential access to active datasets, vector stores, and retrieval-augmented generation pipelines.
• Data Management and Pre-processing: Large-scale ETL, data ingestion, and transformation pipelines that require high-throughput writes and scalable namespace management.

Dell Exascale Storage is a software-defined storage platform that runs PowerScale OneFS, ObjectScale, or — in future releases — Dell Lightning File System and PowerFlex, on a shared hardware foundation: the Dell PowerEdge R7725xd server. The platform is designed for deployments of 10 PB or larger and introduces several architectural capabilities not available in traditional PowerScale appliances.

A key design principle of the Exascale platform is that the same PowerEdge R7725xd hardware can host any of three distinct storage software stacks — without any hardware differences between them. The choice of storage engine is a software licensing decision, not a hardware decision.

• Dell PowerScale OneFS: Industry-leading scale-out NAS for unstructured data. POSIX-compliant, multi-protocol (NFS, SMB, S3, HDFS), with enterprise data protection, SmartSync replication, and the full OneFS security suite. Targeted at AI training pipelines, HPC scratch and home directories, media and entertainment, and general-purpose NAS at extreme scale.
• Dell ObjectScale: High-performance S3-compatible object storage. Designed for AI data lakes, model checkpointing, and large-scale object repositories. ObjectScale on R7725xd (Project Hornet) supports S3 over RDMA with CUDA libraries and GPUDirect Storage integration.
• Dell Lightning File System (future): An extremely high-performance, POSIX-compliant, NCP-compatible parallel file system targeting the most demanding AI training and HPC scratch workloads. Lightning on Exascale is planned for a future release.

The shared hardware foundation enables flexible consumption: a customer who initially deploys nodes as PowerScale can, in a future period of their Total License Agreement, re-license some or all nodes as ObjectScale — or vice versa — without any hardware change. This is a capability Dell calls Exascale substitution, enabled by the Total License Agreement (TLA) mechanism described in the licensing section.

The following table shows the Exascale R7725xd node in context with the existing PowerScale all-flash portfolio. The Exascale platform occupies a new tier above the F910 in performance density and is the only software-defined offering in the lineup:

The PowerEdge R7725xd is a 2U server purpose-engineered for extreme-density NVMe storage workloads. It is the foundational hardware for the Exascale Storage Platform and the first PowerScale node built on AMD EPYC processors.

The R7725xd features 24 PCIe Gen5 NVMe U.2 drive bays, dual 400GbE NVIDIA ConnectX-8 frontend NICs, dual 400GbE backend NICs, and 768 GB of DDR5-6400 memory. In a standard 42U rack, the platform delivers up to 61 PB of raw NVMe capacity.

To the right of the node frontend is the RCP (Right Control Panel).

This RCP sub-assembly contains the following components:

As shown above, the backend PCI slots on an Exascale node are populated as follows:

The Exascale platform runs PowerScale OneFS 9.15 and later releases, leveraging the same industry-leading distributed file system that powers the entire PowerScale portfolio. All OneFS features, protocols, and administrative interfaces are available on Exascale nodes, and Exascale nodes can join existing Ethernet-based PowerScale clusters.

Unlike traditional PowerScale appliance products, where software is bundled into the appliance SKU and licensed per hardware purchase, the Exascale platform uses a separate, subscription-based software licensing model. Hardware is procured through standard Dell server sales channels, and OneFS (or ObjectScale) is licensed independently based on raw storage capacity.

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The Exascale platform supports two deployment models: greenfield (a new dedicated Exascale cluster) and brownfield (expanding an existing PowerScale cluster with Exascale nodes). In both cases, the minimum supported deployment is 3 nodes for initial cluster formation; however, commercial minimums are set at 10 PB of usable capacity.

A greenfield Exascale deployment provisions a new OneFS cluster consisting entirely of R7725xd nodes. This is the primary use case for AI Clouds+ customers building dedicated AI training or inference storage infrastructure from scratch.

Greenfield clusters use the Exascale Phase 1 Pave automation (available from June 2026 general availability) to provision multiple nodes simultaneously. The Pave tooling handles initial OneFS configuration, cluster formation, back-end network setup, and license activation from a single workflow. Engineering-led deployment is available during the initial rollout, transitioning to Dell Professional Services as the customer base scales.

• Back-end networking: Exascale clusters use a shared NVIDIA Spectrum-SN5610 back-end fabric. A standard rack configuration includes two SN5610 switches in redundant pairs.
• Minimum configuration: 3 nodes per cluster formation; 10 PB commercial minimum (RPQ-qualified). A full rack of R7725xd nodes with 122 TB QLC drives reaches 61 PB of raw NVMe capacity.
• Scale-out: Additional R7725xd nodes are added to an existing Exascale cluster through the standard OneFS node addition workflow. Data rebalancing is automatic.

Exascale R7725xd nodes are compatible with existing PowerScale clusters running OneFS 9.15 or later. An organization with an existing F910, F710, or F210 cluster can add Exascale nodes to the same cluster namespace, sharing the same data, directories, and OneFS policies across both node types. This enables a gradual capacity and performance expansion without requiring data migration or cluster replacement.

• OneFS version alignment: The entire cluster must be upgraded to OneFS 9.15 before adding Exascale nodes. Mixed-generation clusters running an older OneFS version cannot add R7725xd nodes.
• Networking alignment: The back-end networking of Exascale nodes (400GbE) operates independently of the back-end networking of prior-generation appliance nodes (100GbE). Both coexist in the same cluster; the 400GbE fabric carries traffic specifically between Exascale nodes.
• Dynamic licensing: In a mixed cluster, traditional appliance node capacity and Exascale node capacity are tracked separately within OneFS. Exascale capacity is billed under the SDS subscription model; appliance node capacity is billed under its original hardware SKU model.

• OneFS FlexProtect provides transparent, distributed data protection across all Exascale nodes. Unlike traditional RAID, FlexProtect distributes protection stripes across all nodes in the cluster, enabling data recovery from simultaneous drive and node failures without the performance penalty of traditional RAID rebuild operations. Protection rebuilds occur in the background during normal cluster operation and can be throttled to minimize impact on foreground workloads.

The larger NVMe drive capacities available on the R7725xd (up to 122 TB per drive) make protection rebuild time a more significant consideration than with prior generations. Dell Technologies recommends selecting appropriate protection policies based on drive capacity and total cluster size; guidance is provided in the OneFS Best Practices Guide for AI Workloads.

The Dell PowerScale Exascale Storage Platform represents a significant evolution in the PowerScale portfolio — the first software-defined, subscription-licensed offering built on a shared hardware foundation across multiple storage engines. By decoupling hardware procurement from software licensing, Dell can deliver the latest PowerEdge server technology to AI and HPC customers faster than traditional appliance cycles allow, addressing a critical gap for organizations whose infrastructure roadmaps demand immediate access to the latest silicon, memory, and NVMe generations.

The PowerEdge R7725xd raises the performance and capacity ceiling for PowerScale: up to 2.88 PB of raw NVMe capacity per 2RU node, 21 GB/s of sequential read throughput, 400GbE front- and back-end networking, and the introduction of AMD EPYC SP5 processors with 96 cores and 768 GB of DDR5 memory. These specifications position the platform to feed the largest GPU clusters — 16,000+ GPUs — without storage becoming the bottleneck.

Key takeaways: The Exascale platform is purpose-built for extreme-scale AI and HPC workloads. It is not a replacement for the broad enterprise NAS market served by the F210, F710, and F910 appliance platforms. Rather, it is a specialized offering for customers with 10 PB or more of storage requirements who value rapid access to the latest server technology, flexible consumption through subscription licensing, and the ability to re-purpose hardware between PowerScale and ObjectScale without hardware changes.

As the needs of the AI storage market continue to grow, the Exascale platform positions Dell to address the most demanding AI and HPC workloads with a software-defined architecture that can evolve rapidly alongside the pace of innovation in GPU compute, networking, and storage media.