| .TH LVREDUCE 8 "LVM TOOLS #VERSION#" "Sistina Software UK" \" -*- nroff -*- |
| .SH NAME |
| lvreduce \(em reduce the size of a logical volume |
| .SH SYNOPSIS |
| .B lvreduce |
| .RB [ \-A | \-\-autobackup |
| .RI { y | n }] |
| .RB [ \-\-commandprofile |
| .IR ProfileName ] |
| .RB [ \-d | \-\-debug ] |
| .RB [ \-h | \-\-help ] |
| .RB [ \-t | \-\-test ] |
| .RB [ \-v | \-\-verbose ] |
| .RB [ \-\-version ] |
| .RB [ \-f | \-\-force ] |
| .RB [ \-\-noudevsync ] |
| .RB { \-l | \-\-extents |
| .RI [ \- ] LogicalExtentsNumber [ % { VG | LV | FREE | ORIGIN }] |
| .RB | |
| .BR \-L | \-\-size |
| .RI [ \- ] LogicalVolumeSize [ bBsSkKmMgGtTpPeE ]} |
| .RB [ \-n | \-\-nofsck ] |
| .RB [ \-\-reportformat |
| .RB { basic | json }] |
| .RB [ \-r | \-\-resizefs ] |
| .IR LogicalVolume { Name | Path } |
| .SH DESCRIPTION |
| 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!!! |
| .br |
| You should therefore ensure that any filesystem on the volume is |
| resized |
| .I before |
| running lvreduce so that the extents that are to be removed are not in use. |
| .br |
| Shrinking snapshot logical volumes (see |
| .BR lvcreate (8) |
| for information to create snapshots) is supported as well. |
| But to change the number of copies in a mirrored logical |
| volume use |
| .BR lvconvert (8). |
| .br |
| 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. |
| .br |
| .SH OPTIONS |
| See \fBlvm\fP(8) for common options. |
| .TP |
| .BR \-f ", " \-\-force |
| Force size reduction without prompting even when it may cause data loss. |
| .TP |
| .IR \fB\-l ", " \fB\-\-extents " [" \- ] LogicalExtentsNumber [ % { VG | LV | FREE | ORIGIN }] |
| Reduce or set the logical volume size in units of logical extents. |
| With the \fI-\fP sign the value will be subtracted from |
| the logical volume's actual size and without it the value will be taken |
| as an absolute size. |
| The total number of physical extents freed will be greater than this logical |
| value if, for example, the volume is mirrored. |
| The number can also be expressed as a percentage of the total space |
| in the Volume Group with the suffix \fI%VG\fP, relative to the existing |
| size of the Logical Volume with the suffix \fI%LV\fP, as a percentage of the |
| remaining free space in the Volume Group with the suffix \fI%FREE\fP, or (for |
| a snapshot) as a percentage of the total space in the Origin Logical |
| Volume with the suffix \fI%ORIGIN\fP. |
| The resulting value for the subtraction is rounded downward, for the absolute |
| size it is rounded upward. |
| N.B. In a future release, when expressed as a percentage with VG or FREE, the |
| number will be treated as an approximate total number of physical extents to be |
| freed (including extents used by any mirrors, for example). The code may |
| currently release more space than you might otherwise expect. |
| .TP |
| .IR \fB\-L ", " \fB\-\-size " [" \- ] LogicalVolumeSize [ bBsSkKmMgGtTpPeE ] |
| Reduce or set the logical volume size in units of megabytes. |
| A size suffix of \fIk\fP for kilobyte, \fIm\fP for megabyte, |
| \fIg\fP for gigabytes, \fIt\fP for terabytes, \fIp\fP for petabytes |
| or \fIe\fP for exabytes is optional. |
| With the \fI\-\fP sign the value will be subtracted from |
| the logical volume's actual size and without it it will be taken as |
| an absolute size. |
| .TP |
| .BR \-n ", " \-\-nofsck |
| Do not perform fsck before resizing filesystem when filesystem |
| requires it. You may need to use \fB\-\-force\fR to proceed with |
| this option. |
| .TP |
| .BR \-\-noudevsync |
| Disable udev synchronisation. The |
| process will not wait for notification from udev. |
| It will continue irrespective of any possible udev processing |
| in the background. You should only use this if udev is not running |
| or has rules that ignore the devices LVM2 creates. |
| .TP |
| .BR \-r ", " \-\-resizefs |
| Resize underlying filesystem together with the logical volume using |
| .BR fsadm (8). |
| .SH Examples |
| Reduce the size of logical volume lvol1 in volume group vg00 by 3 logical extents: |
| .sp |
| .B lvreduce \-l \-3 vg00/lvol1 |
| .SH SEE ALSO |
| .BR fsadm (8), |
| .BR lvchange (8), |
| .BR lvconvert (8), |
| .BR lvcreate (8), |
| .BR lvextend (8), |
| .BR lvm (8), |
| .BR lvresize (8), |
| .BR vgreduce (8) |
