Windows Server 2012 brings a plethora of features built-in to the OS that once required expensive software and hardware add-on purchases. Several of the Windows Server 2012 improvements regard to storage capabilities. Storage Pools combine physical disks into virtual pools to enable aggregation, expansion, and certain administrative tasks. Administrators can create virtual disks out of the pool’s capacity and create volumes out of those disks. When capacity runs low in the pool, simply add more disks to dynamically expand storage capacity. Storage Spaces allows Server Manager administrators to manage those disks, pools, volumes and provisioning for multiple file servers through one screen inside of Server Manager. All of these features can be enabled in all editions of Windows Server 2012, even the OEM-only Foundation edition. As a result, you do not need to pay almost $5000 for your Datacenter license to get these enterprise features! See more about Windows Server 2012 licensing here.
“SAN” via Direct Attached Storage (DAS)
Storage administrators using DAS can turn commodity drives into SAN-like storage. New features built in to Server OS are thin provision with trim support, and expansion of live volumes. Previous features such as striping, mirroring, and pooling JBOD are included and easier to manage. Industry standard SSD, SAS, and low cost SATA disks can be used to create continuously available storage (through failover clustering) to meet business needs without investing in a separate, costly storage environment. Disks cannot be in a RAID array and added to a pool. Only non-RAID or RAID JBOD disks are supported. Server Manager will kick off a nice wizard to create the disk pool and add physical disks as desired.
New file system
The new file system, Resilient File System (ReFS), plays a key supporting role in Storage Spaces and continuous availability. It is backwards compatible with most NTFS features and includes many file system improvements. It supports dynamic shrink and expand tasks run on storage pools across multiple disks, automatic data verification and auto-correction, scale in extreme fashion up to ~262,144 Exabytes (>274 BILLION TB), and keeps the volume online even when the disk is corrupted. CHKDSK speed is vastly improved as well since it scans only the corrupted blocks and not every block on the disk. ReFS is designed solely for file storage and cannot be used for boot drives.
Increase bandwidth with Offloaded Data Transfer (ODX)
ODX provides near-local speed data transfer without high server resource demands. It takes advantage of SMBv3, NIC teaming, as well as multipathing to provide maximum throughput with fault tolerance. ODX increases throughput to and from storage spools by bypassing the OS during data transfer. Instead, ODX passes a token is passed to the OS to track the data movement.
Figure 2 -http://technet.microsoft.com/en-us/library/hh831628.aspx
Storage vendors have been offering data deduplication for several years. Now Microsoft is getting into the game with Windows Server 2012. Microsoft’s data deduplication stores more data in less space by identifying duplicate ‘chunks’ of data and maintaining a single copy of that chunk. Microsoft advertises a typical 2:1 space savings for file servers and 20:1 or better for virtualization data where multiple copies of files are standard. These numbers are far from insignificant. Moreover, enabling this technology after adding it via Role Services requires only a simple checkbox, with minimal optional settings.
New Powershell modules included with Server Manager give administrators uniform and scriptable control over their environment. A comprehensive set of cmdlets can be used for discovery, provisioning disks, snapshot management, replication, creating pools, and volumes. An administrator can use a single script to configure host resources and to configure and present the storage to Windows across many servers from a single prompt.
Storage Spaces and the multitude of supporting components will drastically reduce costs associated with procuring highly or continuously available storage, administrating that storage, and then scaling storage alongside business growth seamlessly. The storage pool model is familiar ground for storage administrators so ramp-up time will be minimal. The new storage stack reduces the layers of administration, yet allows complex configurations as needed to rival many enterprise SAN deployments.