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

p
pvchange(1M) pvchange(1M)
When the only path to a device is detached, the associated physical volume
will be unavailable to the volume group. The path remains part of the
volume group but no I/O is queued to it and the path will remain unused by
LVM until it is reattached. LVM will only stop using the physical volume
when all the paths to the physical volume are detached.
Individually detaching all the paths to a physical volume has the same
consequences as detaching the physical volume entirely using the
-a N
option. The system administrator may safely diagnose or replace hardware
along the path detached, but care should be taken to avoid accessing the
physical volume if it is still being accessed by LVM via other active paths to
it.
N Detach the given path and all other paths to the physical volume. The sys-
tem administrator should always presume that all the disks that belong to
an active volume group are attached and may be used by LVM at any time,
unless LVM has been specifically notified to detach them. Prior to replacing
or repairing any disk belonging to an active volume group, the administra-
tor must first detach the physical volume using this command.
When a physical volume is detached, LVM closes all the paths to the physi-
cal volume and no longer directs any I/O operations to it. If a suitable
spare physical volume is available in the volume group, LVM will use it to
reconstruct the detached disk. The given path must be an attached path to
the physical volume; otherwise, the command will fail and display an error
message indicating the problem.
If for any reason the use of the -a N option fails, the physical volume can
still be detached from the volume group by individually detaching each of
the paths to the physical volume using the -a n option instead.
-s (See WARNINGS section). Immediately begin accessing the associated physical
volume named by pv_path.
-S autoswitch (See WARNINGS section). This option specifies the autoswitch behavior for mul-
tiported physical volumes accessed via multiple paths. It has no effect for physi-
cal 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 the I/O timeout value for the physical volume, to the number of seconds indi-
cated. An I/O timeout value of zero (0) causes the system to use the default
value supplied by the device driver associated with the physical device. I/O
timeout value is used by the device driver to determine how long to wait for disk
transactions to complete before concluding that an I/O request can not be com-
pleted (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
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