Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

80 Administering disks
Disk devices
smallest copy of the configuration database on any of its member
disks.
public region An area that covers the remainder of the disk, and which is used for
the allocation of storage space to subdisks.
A disk’s type identifies how VxVM accesses a disk, and how it manages the disk’s private
and public regions. The following disk access types are used by VxVM:
simple The public and private regions are on the same disk area (with the
public area following the private area).
nopriv There is no private region (only a public region for allocating
subdisks). This is the simplest disk type consisting only of space for
allocating subdisks. Such disks are most useful for defining special
devices (such as RAM disks, if supported) on which private region
data would not persist between reboots. They can also be used to
encapsulate disks where there is insufficient room for a private region.
The disks cannot store configuration and log copies, and they do not
support the use of the
vxdisk addregion command to define
reserved regions. VxVM cannot track the movement of nopriv disks
on a SCSI chain or between controllers.
auto When the
vxconfigd daemon is started, VxVM obtains a list of
known disk device addresses from the operating system and
configures disk access records for them automatically.
Auto-configured disks (with disk access type auto) support the following disk formats:
cdsdisk The disk is formatted as a Cross-platform Data Sharing (CDS) disk
that is suitable for moving between different operating systems. This
is the default format for disks that are not used to boot the
system.Typically, most disks on a system are configured as this disk
type. However, it is not a suitable format for boot, root or swap disks,
for mirrors or hot-relocation spares of such disks, or for Extensible
Firmware Interface (EFI) disks.
hpdisk The disk is formatted as a simple disk. This format can be applied to
disks that are used to boot the system. The disk can be converted to a
CDS disk if it was not initialized for use as a boot disk.
See the
vxcdsconvert(1M) manual page for information about the utility that you can
use to convert disks to the cdsdisk format.
Caution: The CDS disk format is incompatible with EFI disks. If a disk is initialized by
VxVM as a CDS disk, the CDS header occupies the portion of the disk where the partition
table would usually be located. If you subsequently use a command such as fdisk to
create a partition table on a CDS disk, this erases the CDS information and could cause
data corruption.