Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

rootability The ability to place the root file system and the swap device under VxVM control.
The resulting volumes can then be mirrored to provide redundancy and allow
recovery in the event of disk failure.
secondary path In Active/Passive disk arrays, the paths to a disk other than the primary path are
called secondary paths. A disk is supposed to be accessed only through the primary
path until it fails, after which ownership of the disk is transferred to one of the
secondary paths.
sector A unit of size, which can vary between systems. Sector size is set per device (hard
drive, CD-ROM, and so on). Although all devices within a system are usually
configured to the same sector size for interoperability, this is not always the case.
A sector is commonly 1024 bytes.
shared disk group A disk group in which access to the disks is shared by multiple hosts (also referred
to as a cluster-shareable disk group).
shared volume A volume that belongs to a shared disk group and is open on more than one node
of a cluster at the same time.
shared VM disk A VM disk that belongs to a shared disk group in a cluster.
slave node A node that is not designated as the master node of a cluster.
slice The standard division of a logical disk device. The terms partition and slice are
sometimes used synonymously.
snapshot A point-in-time copy of a volume (volume snapshot) or a file system (file system
snapshot).
spanning A layout technique that permits a volume (and its file system or database) that is
too large to fit on a single disk to be configured across multiple physical disks.
sparse plex A plex that is not as long as the volume or that has holes (regions of the plex that
do not have a backing subdisk).
SAN (storage area
network)
A networking paradigm that provides easily reconfigurable connectivity between
any subset of computers, disk storage and interconnecting hardware such as
switches, hubs and bridges.
stripe A set of stripe units that occupy the same positions across a series of columns.
stripe size The sum of the stripe unit sizes comprising a single stripe across all columns
being striped.
stripe unit Equally-sized areas that are allocated alternately on the subdisks (within columns)
of each striped plex. In an array, this is a set of logically contiguous blocks that
exist on each disk before allocations are made from the next disk in the array. A
stripe unit may also be referred to as a stripe element.
567Glossary