Storage Services Technologies
Updated: March 28, 2003
Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2
Storage Services Technologies
Much of the data stored on Microsoft Windows-based servers is critically important for the day-to-day activities in business organizations. Because it is important that employees are able to access and store data reliably, data storage and recovery are a concern for many IT managers. In response to the expanding needs for storage in distributed computing environments, Windows Server 2003 includes several storage technologies that are designed to help you store, access, and manage data on servers.
In this overview
Storage Services Components
This section discusses the components that make up Storage Services:
Virtual Disk Service
Virtual Disk Service
For Windows 2000, each company that made storage devices (for example, hard disks, Peripheral Component Interconnect (PCI) redundant array of independent disks (RAID) adapters, and storage arrays) provided its own application for installing and managing that storage device. As a result, users had to run separate applications for each type of storage device that they used on their computer system. This made it difficult to manage different types of storage devices. To address this issue, Windows Server 2003 introduced Virtual Disk Service (VDS). VDS is a set of application programming interfaces (APIs) that provides a single interface for managing disks. VDS provides an end-to-end solution for managing storage hardware and disks, and for creating volumes on those disks.
Remote Storage is a component that you can use to extend disk space without adding more hard disks. Remote Storage automatically copies eligible files on your local volumes to a library of magnetic tapes or magneto-optical disks. Remote Storage then monitors the amount of space that is available on your local volumes. When the amount of available space on a local volume falls below the level that you designate, Remote Storage automatically removes the content from a sufficient number of eligible files and migrates this content to an attached storage device, which frees up disk space on the volume.
Removable Storage is a component that you can use to track your removable storage media (tapes and optical disks) and manage the hardware libraries that contain them (changers and jukeboxes).
With Removable Storage, you can:
Label, catalog, and track media.
Control library drives, slots, and doors.
Perform drive-cleaning operations.
Removable Storage works together with your data-management applications such as Backup. You use data-management applications to manage the actual data stored on the media. Removable Storage makes it possible for multiple applications to share the same storage media resources, which can reduce your costs. It also provides a common interface for managing those resources, which makes resource management much more efficient.
Storage Services Scenarios
This section describes a few scenarios in which you can use Virtual Disk Service, Removable Storage, and Remote Storage to solve unique storage problems in your organization.
Virtual Disk Service Scenarios
VDS is commonly used in the following scenarios.
Managing LUNs on Hardware Storage Devices
VDS defines a set of features which provide a virtual view of any storage hardware. You can use the VDS APIs to write a storage management application that can manage any other storage hardware RAID arrays and logical unit numbers (LUNs) that have VDS providers. For example, you can use the VDS APIs to create or delete simple, spanned, striped, mirrored, or striped with parity LUNs.
Managing Disks and Volumes
The VDS APIs enable applications to manage disks and volumes. You can create your own application that uses the VDS APIs or use applications such as the Disk Management snap-in or the DiskPart command-line tool (both use the VDS APIs) to perform tasks such as creating or deleting simple, striped, spanned, mirrored or RAID-5 volumes, formatting volumes, assigning drive letters to volumes, and converting basic disks into dynamic disks.
Managing End-To-End Storage Operations
The VDS APIs enable applications to manage end-to-end storage operations. Using the VDS APIs, your application can create a LUN in the storage array, unmask the LUN to a host, create and format a volume on the LUN, and assign a drive letter to the volume.
Remote Storage Scenarios
Remote Storage is commonly used in the following scenarios.
Conserving disk space on managed volumes
You can use Remote Storage to ensure that disk space on the managed volume where your system files are located does not fall below a certain level. This is important if you want to make sure that operating system efficiency is not compromised because of decreased disk space.
Extending disk space on managed volumes
You can use Remote Storage to make additional space available for new, more frequently accessed files, while retaining older, less frequently accessed files that you might need to access some time in the future.
Generating multiple media copies of removable media
You can use Remote Storage to ensure that one or more copies of your migrated files exist on different media in case the original storage medium (disk or tape) becomes unusable.
Replacing damaged removable media while Remote Storage is running
You can use Remote Storage to ensure that when you replace a copy of your migrated files that has become damaged or unusable with another copy of the same files, Remote Storage will, at the same time, automatically generate additional copies on different media.
Recovering from loss of Remote Storage metadata
You can use Remote Storage to ensure that you can retrieve any metadata that is associated with your Remote Storage files.
Removable Storage Scenarios
Removable Storage is commonly used in the following scenarios.
Managing stand-alone drive libraries
You can use Removable Storage to manage multiple single-drive libraries, such as CD-ROM or DVD-ROM drives. A library consists of data-storage media and the device that is used to read from and write to the media – for example, tape and a stand-alone tape drive. You can also use Removable Storage to organize all the media in your libraries into different media pools, and move media between media pools in order to provide the appropriate amount of data storage that your applications require.
Managing automated libraries
You can use Removable Storage to manage automated libraries. Automated libraries are automated units that hold multiple tapes or disks, and some have multiple drives. These libraries are sometimes called changers or jukeboxes, and commonly use robotic subsystems to move media stored in the library's storage slots. You can also use Removable Storage to manage a combination of single-drive and automated libraries.