VERITAS Volume Manager 3.1 Administrator's Guide

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primary path In Active/Passive
type disk arrays, a disk can be
bound to one particular controller
on the disk array or owned by a
controller. The disk can then be
accessed using the path through
this particular controller. See
“path”, “secondary path”.
private disk group A disk group
in which the disks are accessed by
only one specific host.
private region A region of a
physical disk used to store private,
structured Volume Manager
information. The private region
contains a disk header, a table of
contents, and a configuration
database. The table of contents
maps the contents of the disk. The
disk header contains a disk ID. All
data in the private region is
duplicated for extra reliability.
public region A region of a
physical disk managed by the
Volume Manager that contains
available space and is used for
allocating subdisks.
RAID A Redundant Array of
Independent Disks (RAID) is a
disk array set up with part of the
combined storage capacity used for
storing duplicate information
about the data stored in that array.
This makes it possible to
regenerate the data if a disk
failure occurs.
read-writeback mode A
recovery mode in which each read
operationrecoversplex consistency
for the region covered by the read.
Plex consistency is recovered by
reading data from blocks of one
plex and writing the data to all
other writable plexes.
root configuration The
configuration database for the root
disk group.This is special in that it
always contains records for other
disk groups, which are used for
backup purposes only. It also
contains disk records that define
all disk devices on the system.
root disk The disk containing the
root file system. This disk may be
under VxVM control.
root disk group A special
private disk group that always
exists on the system. The root disk
group is named rootdg.
root file system The initial file
system mounted as part of the
UNIX kernel startup sequence.