HP-UX Reference (11i v2 04/09) - 1M System Administration Commands A-M (vol 3)

l
lvchange(1M) lvchange(1M)
NAME
lvchange - change LVM logical volume characteristics
SYNOPSIS
/usr/sbin/lvchange
[-a availability ][-A autobackup ][
-c mirror_consistency][
-C contiguous ]
[
-d schedule ][-D distributed ][
-M mirror_write_cache][
-p permission ][-r relocate ][-s
strict ][-t IO_timeout ] lv_path
Remarks
Mirrored disk operations require the installation of the optional HP MirrorDisk/UX software, which is not
included in the standard HP-UX operating system.
lvchange cannot be performed if the volume group is activated in shared mode.
DESCRIPTION
The
lvchange command changes certain characteristics of a logical volume. Other characteristics can
be changed with the lvextend and lvreduce
commands (see lvextend (1M) and lvreduce (1M)).
The command-line options specify the type and extent of change. Each current characteristic for a logical
volume remains in effect until explicitly changed by the corresponding option. All options take effect
immediately, except
-s, which takes effect only when new extents are allocated by the
lvextend com-
mand.
If a logical volume is striped, its scheduling policy is always parallel and its allocation policy is always
strict and noncontiguous; these attributes cannot be changed with
lvchange.
The
lvchange command can also be used to change the timeout value for a logical volume. This can be
useful to control how long an IO request will be retried (for a transient error, like a device timeout),
before giving up and declaring a pending IO to be failed. The default behavior is for the system to con-
tinue to retry an IO for a transient error until the IO can complete. Thus, the IO will not be returned to
the caller until the IO can complete. By setting a non-zero IO timeout value, this will set the maximum
length of time that the system will retry an IO. If the IO cannot complete before the length of time
specified by the IO timeout, then the IO will be returned to the caller with an error. The actual duration
of the IO request may exceed the logical volume’s maximum IO timeout value when the underlying physi-
cal volume(s) have timeouts which either exceed the logical volume’s timeout value or are not an integer
multiple of the logical volume’s timeout value (see pvchange (1M) for details on how to change the IO
timeout value on a physical volume).
Options and Arguments
The
-c, -d, -M, and -s options are meaningful only if the optional HP MirrorDisk/UX software has been
installed on the system.
lvchange recognizes the following options and arguments:
lv_path The block device path name of a logical volume.
-a availability Set logical volume availability. availability can have one of the following
values:
y Make a logical volume available. An open of the logical volume will
succeed.
n Make a logical volume temporarily unavailable. An open of the log-
ical volume will fail. However, all current processes that have the
logical volume open remain open.
-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.
-c mirror_consistency Set mirror consistency recovery. This option is effective only when -M n
is specified or previously set. mirror_consistency can have one of the
Section 1M−−392 Hewlett-Packard Company − 1 − HP-UX 11i Version 2: September 2004