VGCREATE(8) | System Manager's Manual | VGCREATE(8) |
vgcreate - create a volume group
vgcreate [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-c|--clustered {y|n}] [-d|--debug] [-h|--help] [-l|--maxlogicalvolumes MaxLogicalVolumes] [-M|--metadatatypetype] [-p|--maxphysicalvolumes MaxPhysicalVolumes] [-s|--physicalextentsize PhysicalExtentSize[kKmMgGtT]] [-t|--test] [-v|--verbose] [--version] VolumeGroupName PhysicalVolumePath [PhysicalVolumePath...]
vgcreate creates a new volume group called VolumeGroupName using the block special device PhysicalVolumePath previously configured for LVM with pvcreate(8).
See lvm for common options.
If the new Volume Group contains only local disks that are not visible on the other nodes, you must specify --clustered n. If the cluster infrastructure is unavailable on a particular node at a particular time, you may still be able to use such Volume Groups.
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.
To create a volume group named test_vg using physical volumes /dev/hdk1, and /dev/hdl1 with default physical extent size of 4MB:
vgcreate test_vg /dev/sdk1 /dev/sdl1
lvm(8), pvdisplay(8), pvcreate(8), vgdisplay(8), vgextend(8), vgreduce(8), lvcreate(8), lvdisplay(8), lvextend(8), lvreduce(8)
LVM TOOLS 2.02.44-cvs (02-17-09) | Sistina Software UK |