Microsoft's Windows Server 2012 (formerly code-named Windows Server 8) is due out before the end of 2012, and without a doubt it's one of the most significant releases of the Windows Server operating system to date. The enhancements in Hyper-V promise to put Microsoft's virtualization platform on the same footing as VMware, the new PowerShell integration will enable automated management, and the new Server Manager provides multiserver management. Even with all these new features, the storage enhancements in Windows Server 2012 might very well be the most important changes. Let's explore the top 10 storage enhancements in Windows Server 2012.
10. Revised Chkdsk—One of the more subtle, yet practical, storage enhancements in Windows Server 2012 is the revised Chkdsk utility. With Windows Server 2008 R2 and earlier, if you needed to run Chkdsk, it required a dedicated system and it could take hours to complete on a large volume of stored data. The Windows Server 2012 Chkdsk has been split into two parts. A background process scans the disk; the volume is still online during this process. The second part takes the volume offline while it performs the fixes on problems that were just identified during the scan.
9. VHDX disk format—An important storage enhancement for virtualization is the new VHDX virtual disk format. The new VHDX format significantly extends the size of Virtual Hard Disks (VHDs) by providing support for VHDs with up to 16TB of storage. Previous versions of the VHD format were limited to 2TB.
8. Offloaded Data Transfer (ODX)—Windows Server 2012 has built-in SAN integration with the new ODX technology. ODX can provide significant performance improvements for copy and move operations performed on a SAN by enabling the work of copying or moving the data to be offloaded to the SAN, thus bypassing the need for the Windows Server 2012 OS to handle the data movement.
7. SMB Multichannel—The new Server Message Block (SMB) 2.2 protocol is one of the biggest changes in Windows Server 2012, and one of its coolest features is SMB Multichannel. SMB Multichannel allows multiple TCP connections to be established over multiple NICs for a single SMB session, enabling bandwidth aggregation of the multiple NICs and multiple CPUs involved. The result is greatly improved performance, giving SMB access comparable performance to directly accessed storage.
6. SMB Transparent Failover—The SMB Transparent Failover feature is another new SMB 2.2 feature. SMB Transparent Failover enhances clustering. If a hardware or software failure occurs on a cluster node, all SMB clients can transparently reconnect to another cluster node with no downtime.
5. SMB Scale Out—Another feature in the SMB 2.2 protocol, SMB Scale Out uses Cluster Shared Volumes (CSV) to store file shares that provide simultaneous access through all nodes in a clustered file server. SMB Scale Out provides better utilization of network bandwidth and load balancing of the file server clients.
4. Thin provisioning—Thin provisioning is a feature from Windows Storage Server that has finally made its way to the core Windows Server OS. Thin provisioning optimizes storage utilization by maximizing utilization of existing storage and reclaiming any unused space (aka trimming). Windows Server 2012 allows storage to be allocated on a just-in-time basis—it can identify thin provisioned LUNs, as well as provide notifications for exceeding threshold and physical resource constraints.
3. Data deduplication—Another feature out of Windows Storage Server, data deduplication works at the volume level and stores more data in less physical space. Microsoft claims it provides optimization ratios of 2 to 1 for general file servers and up to 20 to 1 for virtualization data. Data deduplication uses sub-file, variable-size chunking and compression to segment files into small (32KB–128KB) variable-sized chunks. Then it identifies duplicate chunks, maintaining just a single copy of each chunk. Redundant copies of the chunk are replaced by a reference to the single copy.
2. Storage Spaces—Windows Server 2012's new Store Spaces provide a storage solution to organizations and implementations where SANs and NAS devices aren't affordable. With Storage Spaces, the storage is virtualized. The physical disks providing the underlying storage are abstracted from the storage management and aggregated together to be used as a single pool. Data redundancy can be performed automatically. Storage Spaces are designed to work with the new Resilient File System (ReFS).
1. Resilient File System (ReFS)—NTFS has been with us since the initial release of Windows NT back in 1993. Windows Server 2012 breaks new ground by adding ReFS. This new file system has been designed from the ground up with modern computing requirements in mind. It has a high degree of compatibility with the most common NTFS features, but has resiliency and scalability features that go beyond NTFS. ReFS can verify and autocorrect data, and the file system never needs to go offline. ReFS isn't a replacement for NTFS. In the initial release, you can’t boot from ReFS, and ReFs doesn't support conversion from NTFS.