Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

disk access records Configuration records used to specify the access path to particular disks. Each
disk access record contains a name, a type, and possibly some type-specific
information, which is used by VxVM in deciding how to access and manipulate
the disk that is defined by the disk access record.
disk array A collection of disks logically arranged into an object. Arrays tend to provide
benefits such as redundancy or improved performance.
disk array serial number This is the serial number of the disk array. It is usually printed on the disk array
cabinet or can be obtained by issuing a vendor- specific SCSI command to the
disks on the disk array. This number is used by the DMP subsystem to uniquely
identify a disk array.
disk controller In the multipathing subsystem of VxVM, the controller (host bus adapter or HBA)
or disk array connected to the host, which the operating system represents as the
parent node of a disk.
disk enclosure An intelligent disk array that usually has a backplane with a built-in Fibre Channel
loop, and which permits hot-swapping of disks.
disk group A collection of disks that share a common configuration. A disk group
configuration is a set of records containing detailed information on existing VxVM
objects (such as disk and volume attributes) and their relationships. Each disk
group has an administrator-assigned name and an internally defined unique ID.
The disk group names bootdg (an alias for the boot disk group), defaultdg (an
alias for the default disk group) and nodg (represents no disk group) are reserved.
disk group ID A unique identifier used to identify a disk group.
disk ID A universally unique identifier that is given to each disk and can be used to identify
the disk, even if it is moved.
disk media name An alternative term for a disk name.
disk media record A configuration record that identifies a particular disk, by disk ID, and gives that
disk a logical (or administrative) name.
disk name A logical or administrative name chosen for a disk that is under the control of
VxVM, such as disk03. The term disk media name is also used to refer to a disk
name.
dissociate The process by which any link that exists between two VxVM objects is removed.
For example, dissociating a subdisk from a plex removes the subdisk from the
plex and adds the subdisk to the free space pool.
dissociated plex A plex dissociated from a volume.
dissociated subdisk A subdisk dissociated from a plex.
distributed lock
manager
A lock manager that runs on different systems in a cluster, and ensures consistent
access to distributed resources.
593Glossary