[MS-VDS]: Virtual Disk Service (VDS) Protocol Specification

volume managervolume plexThe following terms are specific to this document:active partition: A partition on a master boot record (MBR) disk that becomes the systempartition at system startup if the basic input/output system (BIOS) is configured to selectthat disk for startup. An MBR disk can have exactly one active partition. The activepartition is stored in the partition table on the disk. GUID partitioning table (GPT)disks do not have active partitions. See also master boot record (MBR), systempartition, and partition table.active volume: For volumes that consist of single partitions, active volume is synonymouswith active partition. For volumes that consist of multiple partitions, active volumerefers to a volume in which one of the partitions is an active partition (generally mirroredvolumes because partitions on striped volumes or RAID-5 volumes do not havecomplete copies of volume data). See also active partition.attach: To create and expose a disk device object for a virtual disk on the operating system.For example, when a user creates a virtual disk, a virtual disk file is allocated as thebacking store for the virtual disk. However, creating the virtual disk does not cause anoperating system disk object to be created and exposed; attaching does this.backing store: The virtual disk file that stores the data for a virtual disk.detach: To delete a virtual disk object from the operating system. See attach.differencing chain: The set of virtual disks defined by a differencing disk and its parent orparents. For example, differencing disk A's parent may be differencing disk B, anddifferencing disk B's parent may be virtual disk C. In this example, disks A, B, and Ccreate a differencing chain where disk A is the child and disks B and C are both parents.differencing disk: The current state of a virtual disk represented as a set of modified blocksstoring differences from the parent virtual disk. A differencing disk is not independent; itdepends on the parent virtual disk to be fully functional. A differencing disk may be theparent to another differencing disk. See differencing chain.disk quorum: The minimum number of disks in a disk group that is required to enable theonline status of a disk group. A disk quorum is defined as n/2 + 1, where n is the totalnumber of disks in the group. A disk quorum prevents disk groups from gaining onlinestatus on more than one computer.EUI-64: The IEEE-defined 64-bit extended unique identifier (EUI-64). EUI-64 is aconcatenation of the 24-bit company_id value by the IEEE Registration Authority and a 40-bitextension identifier that is assigned by the organization with that company_id assignment. Formore information, see [EUI64].file system: A set of data structures for naming, organizing, and storing files in a volume.NTFS, FAT, and FAT32 are examples of file system types.full-volume encryption: Encryption of the entire volume, including user files, system files,swap files, and hibernation files.import target: An iSCSI target with which the LUNs being imported to the subsystem areassociated.[MS-VDS] — v20110610Virtual Disk Service (VDS) Protocol SpecificationCopyright © 2011 Microsoft Corporation.Release: Friday, June 10, 201116 / 360