VERITAS Volume Manager 3.1 Administrator's Guide

Disk Tasks
Placing Disks Under Volume Manager Control
Chapter 4 163
Placing Disks Under Volume Manager Control
When you add a disk to a system that is running Volume Manager, you
need to put the disk under Volume Manager control so that the Volume
Manager can control the space allocation on the disk. Unless another
disk group is specified, Volume Manager places new disks in the default
disk group, rootdg. When you are asked to name a disk group, enter
none instead of selecting rootdg or typing in a disk group name. The
disk is then initialized as before, but is reserved for use at a later time. It
cannot be used until it is added to a disk group. Note that this type of
“spare disk” should not be confused with a hot-relocation spare disk.
The method by which you place a disk under Volume Manager control
depends on the circumstances:
• If the disk is new, it must be initialized and placed under Volume
Manager control.
• If the disk is not needed immediately, it can be initialized (but not
added to a disk group) and reserved for future use.
• If the disk was previously initialized for future Volume Manager use,
it can be reinitialized and placed under Volume Manager control.
• If the disk was previously used for a file system, Volume Manager
gives you an option before destroying the file system.
• If the disk was previously in use, but not under Volume Manager
control, you can preserve existing data on the disk while still letting
Volume Manager take control of the disk. This is accomplished using
conversion. With conversion, the virtual layout of the data is fully
converted to Volume Manager’s control (see the VERITAS Volume
Manager Migration Guide).
• Multiple disks on one or more controllers can be placed under Volume
Manager control simultaneously. Depending on the circumstances, all
of the disks may not be processed the same way.
When initializing multiple disks at once, it is possible to exclude
certain disks or certain controllers. To exclude disks, list the names of
the disks to be excluded in the file /etc/vx/disks.exclude before
the initialization. Similarly, you can exclude all disks on specific
controllers from initialization by listing those controllers in the file
/etc/vx/cntrls.exclude.