NAME
pvchange — change characteristics and access path of physical volume in LVM volume group
SYNOPSIS
/usr/sbin/pvchange
[-A
autobackup]
-s
pv_path
/usr/sbin/pvchange
[-A
autobackup]
-S
autoswitch
pv_path
/usr/sbin/pvchange
[-A
autobackup]
-x
extensibility
pv_path
/usr/sbin/pvchange
[-A
autobackup]
-t
IO_timeout
pv_path
/usr/sbin/pvchange
[-A
autobackup]
-z
sparepv
pv_path
Remarks
pvchange
cannot be performed if the volume group is activated in shared mode.
DESCRIPTION
The
pvchange
command changes the characteristics and access path of a physical volume
(pv_path)
in a volume group.
For multiported devices accessed via multiple paths,
pvchange
may be used to customize the circumstances that may cause LVM to
automatically switch from one path to another, or when LVM will switch
back to a prior path which failed when it is available again
(generally described as the physical volume's
autoswitch
behavior).
pvchange
also permits you to switch manually to a specific
path to the physical volume.
pvchange
sets the allocation permission to add physical extents to the physical volume.
If you have installed the optional HP MirrorDisk/UX software, you
can use the
-z
option to designate a spare physical volume to 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.
Options and Arguments
pvchange
recognizes the following options and arguments.
- pv_path
The block device path name of a physical volume.
- -A autobackup
Set automatic backup for this invocation of this command.
autobackup
can have one of the following values:
- y
Automatically back up configuration changes made to the logical volume.
This is the default.
After this command executes, the
vgcfgbackup
command (see
vgcfgbackup(1M))
is executed for the volume group to which the logical volume belongs.
- n
Do not back up configuration changes this time.
- -s
Immediately begin accessing the associated physical volume named by
pv_path.
- -S autoswitch
This option specifies the
autoswitch
behavior for multiported physical volumes accessed via multiple paths.
It has no effect for physical volumes without alternate paths.
autoswitch
option may be set to one of the following values:
- y
LVM is directed to automatically switch from the path it is using whenever a
better path to the physical volume is available.
LVM will switch paths when a better path recovers (after it had
failed earlier), or if the current path fails and another path is available.
This is the default.
- n
LVM is directed to automatically switch to using the best available path only
when the path currently in use is unavailable.
LVM will continue using a specific path for the physical volume
as long as it works, regardless of whether another better path
recovers from a failure.
- -x extensibility
Set the allocation permission to add physical extents to the physical volume
pv_path.
extensibility
can have the following values:
- y
Allow allocation of additional physical extents on the physical volume.
This is the default.
- n
Prohibit allocation of additional physical extents on the physical volume.
However, logical volumes residing on the physical volume are accessible.
- -t IO_timeout
Set
IO_timeout
for the physical volume to the number of seconds indicated. An
IO_timeout
value of zero (0) causes the system to use the default value supplied
by the device driver associated with the physical device.
IO_timeout
is used by the device driver to determine how long to wait for disk
transactions to complete before concluding that an IO request
can not be completed (and the device is offline or unavailable).
- -z sparepv
This option requires the installation of the optional HP MirrorDisk/UX
software. It allows you to change the physical volume specified by
pv_path
into a spare physical volume for its
volume group, or change the specified spare physical volume back into a regular
physical volume for this volume group. No physical extents from
a spare physical volume will be available as part of the "free" pool of
extents in the volume group. A spare physical volume will only be used
in the event that another physical volume within this volume group
becomes unavailable (fails).
sparepv
can have one of the following values:
- y
Change the specified physical volume to be a "stand-by" spare for its
volume group. The specified physical volume must not have extents
allocated on it (i.e., no logical
volumes residing on it) at the time this command is
issued. A stand-by spare physical volume will only be
used in the event of a failure of another physical volume -- prior
to such a failure, no
logical volume is allowed to reside on it.
- n
Change the specified spare physical volume back into a regular physical volume.
If the physical volume was a stand-by spare, then all of the
disk space associated with it will be immediately available for use by
logical volumes. If the physical volume is an "active" spare, that is,
it was previously a stand-by spare but then took over for a
failed physical volume, it will
simply mark the physical volume as a regular member of its volume group
and the logical volumes residing on it will remain unchanged.
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
Prohibit the allocation of additional physical extents to a physical volume:
pvchange -x n /dev/dsk/c0t0d0
Allow the allocation of additional physical extents to a physical volume:
pvchange -x y /dev/dsk/c0t0d0
Only switch paths when the current path is unavailable. Do not
switch back to a prior path which had failed and has recovered,
when the current path works:
pvchange -S n /dev/dsk/c0t0d0
Switch paths whenever a better path becomes available again after a
failure, even if the current path is fine:
pvchange -S y /dev/dsk/c0t0d0
Manually switch a physical volume to use another controller path:
pvchange -s /dev/dsk/c2t0d2
Set the
IO_timeout
value
for a physical volume to 60 seconds:
pvchange -t 60 /dev/dsk/c2t0d2
Set the
IO_timeout
value
for a physical volume to zero (0) to use the driver default:
pvchange -t 0 /dev/dsk/c2t0d2
Change the (empty) physical volume to become a stand-by spare for the volume
group:
pvchange -z y /dev/dsk/c2t0d2
Change the (active or stand-by) spare physical volume to become a regular
member of the volume group:
pvchange -z n /dev/dsk/c2t0d2
Printable version
