HP-UX Reference (11i v3 07/02) - 1M System Administration Commands N-Z (vol 4)

v
vgextend(1M) vgextend(1M)
-x extensibility Set allocation permission for additional physical extents on the physical volume
specified by pv_path. extensibility can have one of the following values:
y Allow allocation of additional physical extents on the physical volume.
n Prohibit allocation of additional physical extents on the physical volume.
Logical volumes residing on the physical volume can still be accessed.
-z sparepv This option requires the installation of the optional HP MirrorDisk/UX software.
It allows you to mark the physical volume(s) specified by pv_path to be either a
spare physical volume or a regular, non-spare physical volume. (A spare physi-
cal volume can be used to replace an existing physical volume within a volume
group when mirroring is in effect, in the event the existing physical volume
fails.) sparepv can have one of the following values:
y The physical volume(s) will be used as spare(s). No physical extents from a
spare physical volume will be available as part of the "free" pool of extents
in the volume group. The spare physical volume(s) will only be used in the
event of another physical volume within this volume group becomes una-
vailable (fails).
n The physical volume(s) will be used as regular, non-spare members of the
volume group. This is the default.
Alternate Links (PVLinks)
In this release of HP-UX, LVM continues to support Alternate Links to a device to allow continued access to
the device, if the primary link fails. This multiple link or multipath solution increases data availability, but
does not allow the multiple paths to be used simultaneously.
There is a new feature introduced in the Mass Storage Subsystem on this version of HP-UX that also sup-
ports multiple paths to a device and allows access to the multiple paths simultaneously. The Mass Storage
Subsystem will balance the I/O load across the valid paths. This new multi-path behavior is enabled and
disabled through the use of the scsimgr command. See scsimgr(1M) for details.
It is no longer required or recommended to configure LVM with alternate links. However, it is possible to
maintain the traditional LVM behavior. To do so, both of the following criteria must be met:
• Only the legacy device special file naming convention is used in the volume group configuration.
• The scsimgr command is used to disable the Mass Storage Subsystem multipath behavior.
EXTERNAL INFLUENCES
Environment Variables
LANG determines the language in which messages are displayed.
If LANG is not specified or is null, it defaults to "C" (see lang(5)).
If any internationalization variable contains an invalid setting, all internationalization variables default to
"C" (see environ(5)).
EXAMPLES
Add physical volumes
/dev/dsk/c0t1d0 and /dev/dsk/c0t2d0
to volume group /dev/vg03 :
vgextend /dev/vg03 /dev/dsk/c0t1d0 /dev/dsk/c0t2d0
Extend physical volume group PVG0 while adding physical volumes /dev/dsk/c0t3d0 and
/dev/dsk/c0t4d0 to volume group /dev/vg03 :
vgextend -g PVG0 /dev/vg03 /dev/dsk/c0t3d0 /dev/dsk/c0t4d0
Add an alternate link to one of the physical volumes in the volume group where /dev/dsk/c0t4d0 and
/dev/dsk/c1t4d0 refer to the same physical volume (referenced via different controllers), and the
volume group already contains /dev/dsk/c0t4d0. /dev/dsk/c0t4d0
remains the primary link (in
use) and
/dev/dsk/c1t4d0 becomes the alternate link.
vgextend /dev/vg03 /dev/dsk/c1t4d0
Add a spare physical volume to a volume group:
vgextend -z y /dev/vg03 /dev/dsk/c2t4d0
636 Hewlett-Packard Company − 2 − HP-UX 11i Version 3: February 2007