VERITAS Volume Manager 3.1 Administrator's Guide

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communicate with each other and
inform VxVM of changes in cluster
membership.
cluster-shareable disk group A
disk group in which the disks are
shared by multiple hosts (also
referred to as a shared disk
group).
column A set of one or more
subdisks within a striped plex.
Striping is achieved by allocating
data alternately and evenly across
the columns within a plex.
concatenation A layout style
characterized by subdisks that are
arranged sequentially and
contiguously.
configuration database A set of
records containing detailed
information on existing Volume
Manager objects (such as disk and
volume attributes).Asingle copy of
a configuration database is called a
configuration copy.
data stripe This represents the
usable data portion of a stripe and
is equal to the stripe minus the
parity region.
detached A state in which a
VxVM object is associated with
another object, but not enabled for
use.
device name The device name or
address used to access a physical
disk, such as c0t0d0. The c#t#d#
syntax identifies the controller,
target address, and disk.
Dirty Region Logging The
procedure by which the Volume
Manager monitors and logs
modifications to a plex. A bitmap of
changed regions is kept in an
associated subdisk called a log
subdisk.
disabled path A path to a disk
that is not available for I/O. A path
can be disabled due to real
hardware failures or if the user
has used the vxdmpadm disable
command on that controller.
disk A collection of read/write
data blocks that are indexed and
can be accessed fairly quickly.
Each disk has a universally unique
identifier.
disk access name Thenameused
to access a physical disk, such as
c0t0d0. The c#t#d#s# syntax
identifies the controller, target
address, disk, and partition. The