HP-UX Reference (11i v1 05/09) - 1M System Administration Commands A-M (vol 3)

lvreduce(1M) lvreduce(1M)

One, and only one, -l, -L

,or-m option must be speciﬁed.

-m mirror_copies Reduce the number of mirror copies allocated for each logical extent. A mirror

copy contains the same data as the original. mirror_copies can have the value

or 1. It must be smaller than the current value.

If optional pv_path arguments are speciﬁed, the mirror copies are deallocated

from the speciﬁed physical volumes.

One, and only one, -l, -L

,or-m option must be speciﬁed.

-k This option should be used only in the special instance when you want to reduce

a mirrored logical volume on a physical volume that is missing or has failed.

Use this option with the -m option.

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

Decrease the number of the logical extents of a logical volume to one hundred:

lvreduce -l 100 /dev/vg01/lvol3

Reduce to one mirror (that is, an original and one copy) for each logical extent of a logical volume:

lvreduce -m 1 /dev/vg01/lvol5

Remove mirror copies of logical extents of a logical volume from the physical volume

/dev/dsk/c1t0d0:

lvreduce -m 0 /dev/vg01/lvol4 /dev/dsk/c1t0d0

Remove a logical volume from a one-way mirrored set on the speciﬁed pv_path.

lvreduce -m 0 -k /dev/vg01/lvol1 /dev/dsk/c1t0d0

WARNINGS

LVM does not store any information about which physical extents within a logical volume contain useful

data; therefore, reducing the space allocated to a logical volume without doing a prior backup of the data

could lead to the loss of useful data. The lvreduce command on a logical volume containing a ﬁle system

of greater length than the size being reduced to will cause data corruption.

To reduce a logical volume being used for swap, that swap area must not be currently in use.