Announcing Native NVMe in Windows Server 2025: Ushering in a New Era of Storage Performance
We’re thrilled to announce the arrival of Native NVMe support in Windows Server 2025—a leap forward in storage innovation that will redefine what’s possible for your most demanding workloads. Modern NVMe (Non-Volatile Memory Express) SSDs now operate more efficiently with Windows Server. This improvement comes from a redesigned Windows storage stack that no longer treats all storage devices as SCSI (Small Computer System Interface) devices—a method traditionally used for older, slower drives. By eliminating the need to convert NVMe commands into SCSI commands, Windows Server reduces processing overhead and latency. Additionally, the whole I/O processing workflow is redesigned for extreme performance. This release is the result of close collaboration between our engineering teams and hardware partners, and it serves as a cornerstone in modernizing our storage stack. Native NVMe is now generally available (GA) with an opt-in model (disabled by default as of October’s latest cumulative update for WS2025). Switch onto Native NVMe as soon as possible or you are leaving performance gains on the table! Stay tuned for more updates from our team as we transition to a dramatically faster, more efficient storage future. Why Native NVMe and why now? Modern NVMe devices—like PCIe Gen5 enterprise SSDs capable of 3.3 million IOPS, or HBAs delivering over 10 million IOPS on a single disk—are pushing the boundaries of what storage can do. SCSI-based I/O processing can’t keep up because it uses a single-queue model, originally designed for rotational disks, where protocols like SATA support just one queue with up to 32 commands. In contrast, NVMe was designed from the ground up for flash storage and supports up to 64,000 queues, with each queue capable of handling up to 64,000 commands simultaneously. With Native NVMe in Windows Server 2025, the storage stack is purpose-built for modern hardware—eliminating translation layers and legacy constraints. Here’s what that means for you: Massive IOPS Gains: Direct, multi-queue access to NVMe devices means you can finally reach the true limits of your hardware. Lower Latency: Traditional SCSI-based stacks rely on shared locks and synchronization mechanisms in the kernel I/O path to manage resources. Native NVMe enables streamlined, lock-free I/O paths that slash round-trip times for every operation. CPU Efficiency: A leaner, optimized stack frees up compute for your workloads instead of storage overhead. Future-Ready Features: Native support for advanced NVMe capabilities like multi-queue and direct submission ensures you’re ready for next-gen storage innovation. Performance Data Using DiskSpd.exe, basic performance testing shows that with Native NVMe enabled, WS2025 systems can deliver up to ~80% more IOPS and a ~45% savings in CPU cycles per I/O on 4K random read workloads on NTFS volumes when compared to WS2022. This test ran on a host with Intel Dual Socket CPU (208 logical processors, 128GB RAM) and a Solidigm SB5PH27X038T 3.5TB NVMe device. The test can be recreated by running "diskspd.exe -b4k -r -Su –t8 -L -o32 -W10 -d30" and modifying the parameters as desired. Results may vary. Top Use Cases: Where You’ll See the Difference Try Native NVMe on servers running your enterprise applications. These gains are not just for synthetic benchmarks—they translate directly to faster database transactions, quicker VM operations, and more responsive file and analytics workloads. SQL Server and OLTP: Shorter transaction times, higher IOPS, and lower tail latency under mixed read/write workloads. Hyper‑V and virtualization: Faster VM boot, checkpoint operations, and live migration with reduced storage contention. High‑performance file servers: Faster large‑file reads/writes and quicker metadata operations (copy, backup, restore). AI/ML and analytics: Low‑latency access to large datasets and faster ETL, shuffle, and cache/scratch I/O. How to Get Started Check your hardware: Ensure you have NVMe-capable devices that are currently using the Windows NVMe driver (StorNVMe.sys). Note that some NVMe device vendors provide their own drivers, so unless using the in-box Windows NVMe driver, you will not notice any differences. Enable Native NVMe: After applying the 2510-B Latest Cumulative Update (or most recent), add the registry key with the following PowerShell command: reg add HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides /v 1176759950 /t REG_DWORD /d 1 /f Alternatively, use this Group Policy MSI to add the policy that controls the feature then run the local Group Policy Editor to enable the policy (found under Local Computer Policy > Computer Configuration > Administrative Templates > KB5066835 251014_21251 Feature Preview > Windows 11, version 24H2, 25H2). Once Native NVMe is enabled, open Device Manager and ensure that all attached NVMe devices are displayed under the “Storage disks” section. Monitor and Validate: Use Performance Monitor and Windows Admin Center to see the gains for yourself. Or try DiskSpd.exe yourself to measure microbenchmarks in your own environment! A quick way to measure IOPS in Performance Monitor is to set up a histogram chart and add a counter for Physical Disk>Disk Transfers/sec (where the selected instance is a drive that corresponds to one of your attached NVMe devices) then run a synthetic workload with DiskSpd. Compare the numbers before and after enabling Native NVMe to see the realized difference in your real environment! Join the Storage Revolution This is more than just a feature—it’s a new foundation for Windows Server storage, built for the future. We can’t wait for you to experience the difference. Share your feedback, ask questions, and join the conversation. Let’s build the future of high-performance Windows Server storage together. Send us your feedback or questions at nativenvme@microsoft.com! — Yash Shekar (and the Windows Server team)Cache drive reconfiguration in Server 2025 Storage Spaces Direct cluster
We have a three node S2D cluster running Server 2025, with the storage in a 3 way mirror, running Hyper-V VMs. Each node has 4 x NVMe drives that are currently being used as cache drives, but which are connected to a RAID controller (in HBA mode), so in the S2D configuration they appear as SSD drives rather than NVMe drives. We've purchased the required cables and drive bays to be able to reconfigure the NVMe drives so that they're attached directly to the PCIe bus, so they'll show up as NVMe drives and hopefully give us a performance boost, so I'm just trying to plan the reconfiguration. I was hoping it would be a relatively simple process of shutting everything down, reconfiguring the storage and bringing everything back online, but ChatGPT suggests things won't be that easy and that a complete reconfiguration of the storage would be required. So in a nutshell, can the cache drives be reconfigured without a complete rebuild of the S2D storage ? Cheers, Rob
vNVMe on Hyper-V to unlock PCIe 5.0 NVMe performance
On hosts with NVMe PCIe 5.0 (E3.S/U.2), Hyper-V guests still use virtual SCSI and leave a lot of performance on the table. We are paying for top-tier storage, yet software becomes the limiter. A virtual NVMe device that preserves checkpoints/Replica/Live Migration would align guest performance with modern hardware without forcing DDA and its operational trade-offs.26063 deduplication data corruption is still there.
From Server 2022 up to this newest 26063 build, they all have the same problem, as described here: https://techcommunity.microsoft.com/t5/windows-server-insiders/server-vnext-26040-and-server-2022-deduplication-data-corruption/m-p/4047321 I am out of energy for today and give up for today. It seems to be impossible to get Microsoft to care for actual OS bugs instead of marketing.
S2D FaultDomainAwareness
We're setting up a 2 Node windows 2025 cluster with storage spaces direct After creating the pool we created two virtual disk but see the following output PS C:\WINDOWS\system32> Get-VirtualDisk | Format-List FriendlyName, Size, FaultDomainAwareness FriendlyName : ClusterPerformanceHistory Size : 25769803776 FaultDomainAwareness : StorageScaleUnit FriendlyName : S2DVOL01 Size : 10995116277760 FaultDomainAwareness : FriendlyName : S2DVOL02 Size : 10995116277760 FaultDomainAwareness : The FaultDomainAwareness is empty for the two virtual disk created on the storage pool which is configured like this PS C:\WINDOWS\system32> Get-StoragePool –FriendlyName S2D-CLHV-001-Pool | Format-List FriendlyName, Size, FaultDomainAwarenessDefault FriendlyName : S2D-CLHV-001-Pool Size : 57592038555648 FaultDomainAwarenessDefault : StorageScaleUnit is there something wrong ?Allow for the expansion of physical disks in a storage pool
Allow for the expansion of physical disks in a storage pool just like lvm on Linux. This would be useful in virtual environments and in Azure to be able to expand the physical representation of the virtual disk file. Be it a vmdk or vhdx. This currently allowable on other modern logical volume managers out there. This should be trivial to modify since the meta data is already there. It could be added to the powershell commandlets to rescan-physicaldisk, which would rebuild the metadata on the pool. I have a feedback hub suggestion open on it, which if you could please upvote: https://aka.ms/AAy4ihw
Announcing Windows Server vNext Preview Build 26445
Announcing Windows Server vNext Preview Build 26445 Hello Windows Server Insiders! Today we are pleased to release a new build of the next Windows Server Long-Term Servicing Channel (LTSC) Preview that contains both the Desktop Experience and Server Core installation options for Datacenter and Standard editions, Annual Channel for Container Host and Azure Edition (for VM evaluation only). Branding remains, Windows Server 2025, in this preview - when reporting issues please refer to Windows Server vNext preview. If you signed up for Server Flighting, you should receive this new build automatically. What's New [NEW] Rack Level Nested Mirror (RLNM) for S2D Campus Cluster Rack Level Nested Mirror (RLNM) for S2D Campus Cluster enables customers to meet NIS2 two data room requirements for their factories by providing fast and resilient storage using Storage Spaces Direct (S2D). For S2D Campus Cluster, we recommend using all-flash storage (SSD or NVMe drives), all capacity (no cache drives), and RDMA NICs (iWARP, RoCE, or InfiniBand). Note: Rack fault domains must be created on the cluster in order to use this feature – a new cluster must be created: #Create a test cluster but do not create storage: New-Cluster -Name TestCluster -Node Node1, Node2, Node3, Node4 -NoStorage #Define the fault domains for the cluster – two nodes are in “Room1” and two nodes are in “Room2”: Set-ClusterFaultDomain -XML @”<Topology><Site Name=”Redmond”><Rack Name=”Room1”><Node Name=”Node1”/><Node Name=”Node2”/></Rack><Rack Name=”Room2”><Node Name=”Node3”/> <Node Name=”Node4”/></Rack></Site></Topology>”@ #Add Storage Spaces Direct (S2D) Storage to the cluster – note that Enable-ClusterS2D cmdlet can also be used: Enable-ClusterStorageSpacesDirect #Update the Storage Pool Update-StoragePool #Check that the StoragePool version is 29: (Get-CimInstance -Namespace root/microsoft/windows/storage -ClassName MSFT_StoragePool -Filter 'IsPrimordial = false').CimInstanceProperties['Version'].Value #Check that the Storage Pool’s FaultDomainAwareness property is set to StorageRack: Get-storagepool -FriendlyName <S2DStoragePool> | fl #Note that resiliency is specified when the volume is created – our idea with the S2D Campus cluster is that customers can create both four-copy and two-copy volumes - valuable workload (VMs) and data should go on the 4-copy volumes. #Create a four-copy volume on the storage pool, fixed provisioned: New-Volume -FriendlyName “FourCopyVolumeFixed” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -ResiliencySettingName Mirror -PhysicalDiskRedundancy 3 -ProvisioningType Fixed -NumberOfDataCopies 4 –NumberOfColumns 3 #Optional - Create a four-copy volume on the storage pool, thinly provisioned: New-Volume -FriendlyName “FourCopyVolumeThin” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -ResiliencySettingName Mirror -PhysicalDiskRedundancy 3 –ProvisioningType Thin -NumberOfDataCopies 4 –NumberOfColumns 3 #Optional - Create a two-copy volume on the storage pool, fixed provisioned: New-Volume -FriendlyName “TwoCopyVolumeFixed” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -ResiliencySettingName Mirror -PhysicalDiskRedundancy 1 -ProvisioningType Fixed #Optional - Create a two-copy volume on the storage pool, thinly provisioned: New-Volume -FriendlyName “TwoCopyVolumeThin” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -ResiliencySettingName Mirror -PhysicalDiskRedundancy 1 -ProvisioningType Thin Windows Server Flighting is here!! If you signed up for Server Flighting, you should receive this new build automatically today. For more information, see Welcome to Windows Insider flighting on Windows Server - Microsoft Community Hub. Feedback Hub app is now available for Server Desktop users! The app should automatically update with the latest version, but if it does not, simply Check for updates in the app’s settings tab. Known Issues Download Windows Server Insider Preview (microsoft.com) Flighting: The label for this flight may incorrectly reference Windows 11. However, when selected, the package installed is the Windows Server update. Please ignore the label and proceed with installing your flight. This issue will be addressed in a future release. Available Downloads Downloads to certain countries may not be available. See Microsoft suspends new sales in Russia - Microsoft On the Issues. Windows Server Long-Term Servicing Channel Preview in ISO format in 18 languages, and in VHDX format in English only. Windows Server Datacenter Azure Edition Preview in ISO and VHDX format, English only. Microsoft Server Languages and Optional Features Preview Keys: Keys are valid for preview builds only. Server Standard: MFY9F-XBN2F-TYFMP-CCV49-RMYVH Datacenter: 2KNJJ-33Y9H-2GXGX-KMQWH-G6H67 Azure Edition does not accept a key Symbols: Available on the public symbol server – see Using the Microsoft Symbol Server. Expiration: This Windows Server Preview will expire September 15, 2025. How to Download Registered Insiders may navigate directly to the Windows Server Insider Preview download page. If you have not yet registered as an Insider, see GETTING STARTED WITH SERVER on the Windows Insiders for Business portal. We value your feedback! The most important part of the release cycle is to hear what's working and what needs to be improved, so your feedback is extremely valued. Please use the new Feedback Hub app for Windows Server if you are running a Desktop version of Server. If you are using a Core edition, or if you are unable to use the Feedback Hub app, you can use your registered Windows 10 or Windows 11 Insider device and use the Feedback Hub application. In the app, choose the Windows Server category and then the appropriate subcategory for your feedback. In the title of the Feedback, please indicate the build number you are providing feedback on as shown below to ensure that your issue is attributed to the right version: [Server #####] Title of my feedback See Give Feedback on Windows Server via Feedback Hub for specifics. The Windows Server Insiders space on the Microsoft Tech Communities supports preview builds of the next version of Windows Server. Use the forum to collaborate, share and learn from experts. For versions that have been released to general availability in market, try the Windows Server for IT Pro forum or contact Support for Business. Diagnostic and Usage Information Microsoft collects this information over the internet to help keep Windows secure and up to date, troubleshoot problems, and make product improvements. Microsoft server operating systems can be configured to turn diagnostic data off, send Required diagnostic data, or send Optional diagnostic data. During previews, Microsoft asks that you change the default setting to Optional to provide the best automatic feedback and help us improve the final product. Administrators can change the level of information collection through Settings. For details, see http://aka.ms/winserverdata. Also see the Microsoft Privacy Statement. Terms of Use This is pre-release software - it is provided for use "as-is" and is not supported in production environments. Users are responsible for installing any updates that may be made available from Windows Update. All pre-release software made available to you via the Windows Server Insider program is governed by the Insider Terms of Use.Announcing Windows Server vNext Preview Build 26454
Announcing Windows Server vNext Preview Build 26454 Hello Windows Server Insiders! Today we are pleased to release a new build of the next Windows Server Long-Term Servicing Channel (LTSC) Preview that contains both the Desktop Experience and Server Core installation options for Datacenter and Standard editions, Annual Channel for Container Host and Azure Edition (for VM evaluation only). Branding remains, Windows Server 2025, in this preview - when reporting issues please refer to Windows Server vNext preview. If you signed up for Server Flighting, you should receive this new build automatically. What's New Rack Level Nested Mirror (RLNM) for S2D Campus Cluster Rack Level Nested Mirror (RLNM) for S2D Campus Cluster enables customers to meet NIS2 two data room requirements for their factories by providing fast and resilient storage using Storage Spaces Direct (S2D). For S2D Campus Cluster, we recommend using all-flash storage (SSD or NVMe drives), all capacity (no cache drives), and RDMA NICs (iWARP, RoCE, or InfiniBand). Note: Rack fault domains must be created on the cluster in order to use this feature – a new cluster must be created: #Create a test cluster but do not create storage: New-Cluster -Name TestCluster -Node Node1, Node2, Node3, Node4 -NoStorage #Define the fault domains for the cluster – two nodes are in “Room1” and two nodes are in “Room2”: Set-ClusterFaultDomain -XML @”<Topology><Site Name=”Redmond”><Rack Name=”Room1”><Node Name=”Node1”/><Node Name=”Node2”/></Rack><Rack Name=”Room2”><Node Name=”Node3”/> <Node Name=”Node4”/></Rack></Site></Topology>”@ #Add Storage Spaces Direct (S2D) Storage to the cluster – note that Enable-ClusterS2D cmdlet can also be used: Enable-ClusterStorageSpacesDirect #Check that the Storage Pool’s FaultDomainAwareness property is set to StorageRack: Get-storagepool -FriendlyName <S2DStoragePool> | fl #Create a four-copy volume on the storage pool: New-Volume -FriendlyName “FourCopyVolume” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -PhysicalDiskRedundancy 3 -ProvisioningType Fixed -NumberOfDataCopies 4 –NumberOfColumns 3 #Create a four-copy volume on the storage pool, thinly provisioned: New-Volume -FriendlyName “FourCopyVolume” -StoragePoolFriendlyName S2D* -FileSystem CSVFS_ReFS –Size 500GB -PhysicalDiskRedundancy 3 –ProvisioningType Thin -NumberOfDataCopies 4 –NumberOfColumns 3 Windows Server Flighting is here!! If you signed up for Server Flighting, you should receive this new build automatically today. For more information, see Welcome to Windows Insider flighting on Windows Server - Microsoft Community Hub. Feedback Hub app is now available for Server Desktop users! The app should automatically update with the latest version, but if it does not, simply Check for updates in the app’s settings tab. Known Issues Download Windows Server Insider Preview (microsoft.com) Flighting: The label for this flight may incorrectly reference Windows 11. However, when selected, the package installed is the Windows Server update. Please ignore the label and proceed with installing your flight. This issue will be addressed in a future release. Available Downloads Downloads to certain countries may not be available. See Microsoft suspends new sales in Russia - Microsoft On the Issues. Windows Server Long-Term Servicing Channel Preview in ISO format in 18 languages, and in VHDX format in English only. Windows Server Datacenter Azure Edition Preview in ISO and VHDX format, English only. Microsoft Server Languages and Optional Features Preview Keys: Keys are valid for preview builds only. Server Standard: MFY9F-XBN2F-TYFMP-CCV49-RMYVH Datacenter: 2KNJJ-33Y9H-2GXGX-KMQWH-G6H67 Azure Edition does not accept a key Symbols: Available on the public symbol server – see Using the Microsoft Symbol Server. Expiration: This Windows Server Preview will expire September 15, 2025. How to Download Registered Insiders may navigate directly to the Windows Server Insider Preview download page. If you have not yet registered as an Insider, see GETTING STARTED WITH SERVER on the Windows Insiders for Business portal. We value your feedback! The most important part of the release cycle is to hear what's working and what needs to be improved, so your feedback is extremely valued. Please use the new Feedback Hub app for Windows Server if you are running a Desktop version of Server. If you are using a Core edition, or if you are unable to use the Feedback Hub app, you can use your registered Windows 10 or Windows 11 Insider device and use the Feedback Hub application. In the app, choose the Windows Server category and then the appropriate subcategory for your feedback. In the title of the Feedback, please indicate the build number you are providing feedback on as shown below to ensure that your issue is attributed to the right version: [Server #####] Title of my feedback See Give Feedback on Windows Server via Feedback Hub for specifics. The Windows Server Insiders space on the Microsoft Tech Communities supports preview builds of the next version of Windows Server. Use the forum to collaborate, share and learn from experts. For versions that have been released to general availability in market, try the Windows Server for IT Pro forum or contact Support for Business. Diagnostic and Usage Information Microsoft collects this information over the internet to help keep Windows secure and up to date, troubleshoot problems, and make product improvements. Microsoft server operating systems can be configured to turn diagnostic data off, send Required diagnostic data, or send Optional diagnostic data. During previews, Microsoft asks that you change the default setting to Optional to provide the best automatic feedback and help us improve the final product. Administrators can change the level of information collection through Settings. For details, see http://aka.ms/winserverdata. Also see the Microsoft Privacy Statement. Terms of Use This is pre-release software - it is provided for use "as-is" and is not supported in production environments. Users are responsible for installing any updates that may be made available from Windows Update. All pre-release software made available to you via the Windows Server Insider program is governed by the Insider Terms of Use.
Server 2022, network drives and content searching
We have two drives with close to 1TB of data, The one drive has a specific folder where end users want to search for a file using content from the files. The files are generally .xls based files End users are 99% Windows 11 based and server is server 2022. Indexing on the server with content aware filtering has occurred and can find the files when searching for their names however not when searching content. This needs to happen using Windows Search in explorer. Data is unstructured, however structured in a folder system. (Year, month, etc) I have read that Windows Content Search is not supported on network drives, can this be confirmed? Any suggestions on a resolution would be appreciated.
