lvreduce allows you to reduce the size of a logical volume.
Be careful when reducing a logical volume's size, because data in the
reduced part is lost!!!
You should therefore ensure that any filesystem on the volume is
resized
before
running lvreduce so that the extents that are to be removed are not in use.
Shrinking snapshot logical volumes (see
lvcreate(8)
for information to create snapshots) is supported as well.
But to change the number of copies in a mirrored logical
volume use
lvconvert (8).
Sizes will be rounded if necessary - for example, the volume size must
be an exact number of extents and the size of a striped segment must
be a multiple of the number of stripes.
Reduce or set the logical volume size in units of logical extents.
With the - sign the value will be subtracted from
the logical volume's actual size and without it the will be taken as
an absolute size.
The number can also be expressed as a percentage of the total space
in the Volume Group with the suffix %VG or relative to the existing
size of the Logical Volume with the suffix %LV or as a percentage of the remaining
free space in the Volume Group with the suffix %FREE.
-L, --size [-]LogicalVolumeSize[kKmMgGtTpPeE]
Reduce or set the logical volume size in units of megabyte by default.
A size suffix of k for kilobyte, m for megabyte,
g for gigabytes, t for terabytes, p for petabytes
or e for exabytes is optional.
With the - sign the value will be subtracted from
the logical volume's actual size and without it it will be taken as
an absolute size.
Example
"lvreduce -l -3 vg00/lvol1" reduces the size of logical volume lvol1
in volume group vg00 by 3 logical extents.
