mirror of
git://sourceware.org/git/lvm2.git
synced 2024-12-25 01:34:38 +03:00
111 lines
3.8 KiB
Groff
111 lines
3.8 KiB
Groff
.TH VGCREATE 8 "LVM TOOLS" "Sistina Software UK" \" -*- nroff -*-
|
|
.SH NAME
|
|
vgcreate \- create a volume group
|
|
.SH SYNOPSIS
|
|
.B vgcreate
|
|
.RB [ \-\-addtag
|
|
.IR Tag ]
|
|
.RB [ \-\-alloc
|
|
.IR AllocationPolicy ]
|
|
.RB [ \-A | \-\-autobackup " {" y | n }]
|
|
.RB [ \-c | \-\-clustered " {" y | n }]
|
|
.RB [ \-d | \-\-debug ]
|
|
.RB [ \-h | \-\-help ]
|
|
.RB [ \-l | \-\-maxlogicalvolumes
|
|
.IR MaxLogicalVolumes ]
|
|
.RB [ -M | \-\-metadatatype type]
|
|
.RB [ -p | \-\-maxphysicalvolumes
|
|
.IR MaxPhysicalVolumes ]
|
|
.RB [ \-s | \-\-physicalextentsize
|
|
.IR PhysicalExtentSize [ \fBkKmMgGtT\fR ]]
|
|
.RB [ \-t | \-\-test ]
|
|
.RB [ \-v | \-\-verbose ]
|
|
.RB [ \-\-version ]
|
|
.I VolumeGroupName PhysicalVolumePath
|
|
.RI [ PhysicalVolumePath ...]
|
|
.SH DESCRIPTION
|
|
.B vgcreate
|
|
creates a new volume group called
|
|
.I VolumeGroupName
|
|
using the block special device
|
|
.IR PhysicalVolumePath
|
|
previously configured for LVM with
|
|
.BR pvcreate (8).
|
|
.SH OPTIONS
|
|
See \fBlvm\fP for common options.
|
|
.TP
|
|
.BR \-c ", " \-\-clustered " " { y | n }
|
|
If clustered locking is enabled, this defaults to \fBy\fP indicating that
|
|
this Volume Group is shared with other nodes in the cluster.
|
|
|
|
If the new Volume Group contains only local disks that are not visible
|
|
on the other nodes, you must specify \fB\-\-clustered\ n\fP.
|
|
If the cluster infrastructure is unavailable on a particular node at a
|
|
particular time, you may still be able to use such Volume Groups.
|
|
.TP
|
|
.BR \-l ", " \-\-maxlogicalvolumes " " \fIMaxLogicalVolumes\fR
|
|
Sets the maximum number of logical volumes allowed in this
|
|
volume group.
|
|
The setting can be changed with \fBvgchange\fP.
|
|
For volume groups with metadata in lvm1 format, the limit
|
|
and default value is 255.
|
|
If the metadata uses lvm2 format, the default value is 0
|
|
which removes this restriction: there is then no limit.
|
|
.TP
|
|
.BR \-p ", " \-\-maxphysicalvolumes " " \fIMaxPhysicalVolumes\fR
|
|
Sets the maximum number of physical volumes that can belong
|
|
to this volume group.
|
|
The setting can be changed with \fBvgchange\fP.
|
|
For volume groups with metadata in lvm1 format, the limit
|
|
and default value is 255.
|
|
If the metadata uses lvm2 format, the default value is 0
|
|
which removes this restriction: there is then no limit.
|
|
If you have a large number of physical volumes in
|
|
a volume group with metadata in lvm2 format,
|
|
for tool performance reasons, you should consider
|
|
some use of \fB--metadatacopies 0\fP
|
|
as described in \fBpvcreate(8)\fP.
|
|
.TP
|
|
.BR \-s ", " \-\-physicalextentsize " " \fIPhysicalExtentSize\fR[\fBkKmMgGtT\fR]
|
|
Sets the physical extent size on physical volumes of this volume group.
|
|
A size suffix (k for kilobytes up to t for terabytes) is optional, megabytes
|
|
is the default if no suffix is present.
|
|
The default is 4 MB and it must be at least 1 KB and a power of 2.
|
|
|
|
Once this value has been set, it is difficult to change it without recreating
|
|
the volume group which would involve backing up and restoring data on any
|
|
logical volumes. However, if no extents need moving for the new
|
|
value to apply, it can be altered using vgchange \-s.
|
|
|
|
If the volume group metadata uses lvm1 format, extents can vary in size from
|
|
8KB to 16GB and there is a limit of 65534 extents in each logical volume. The
|
|
default of 4 MB leads to a maximum logical volume size of around 256GB.
|
|
|
|
If the volume group metadata uses lvm2 format those restrictions do not apply,
|
|
but having a large number of extents will slow down the tools but have no
|
|
impact on I/O performance to the logical volume. The smallest PE is 1KB.
|
|
|
|
The 2.4 kernel has a limitation of 2TB per block device.
|
|
.SH EXAMPLES
|
|
To create a volume group named
|
|
.B test_vg
|
|
using physical volumes
|
|
.BR /dev/hdk1 ", and " /dev/hdl1
|
|
with default physical extent size of 4MB:
|
|
.nf
|
|
|
|
\ vgcreate test_vg /dev/sdk1 /dev/sdl1
|
|
|
|
.fi
|
|
.SH SEE ALSO
|
|
.BR lvm (8),
|
|
.BR pvdisplay (8),
|
|
.BR pvcreate (8),
|
|
.BR vgdisplay (8),
|
|
.BR vgextend (8),
|
|
.BR vgreduce (8),
|
|
.BR lvcreate (8),
|
|
.BR lvdisplay (8),
|
|
.BR lvextend (8),
|
|
.BR lvreduce (8)
|