vgcreate(8) — Maintenance

OSF — Environment_Note_Added

NAME

vgcreate − Creates a volume group

SYNOPSIS

vgcreate [-x Extensibility] [-e MaxPhysicalExtents] [-l MaxLogicalVolumes] [-p MaxPhysicalVolumes] [-s PhysicalExtentSize] [-v VGDA] VolumeGroupName PhysicalVolumePath ...

FLAGS

-x Extensibility
Sets the allocation permission for adding physical extents on the physical volumes specified by the PhysicalVolumePath parameter. The Extensibility parameter is represented by one of the following:

yAllows the allocation of additional physical extents on the physical volume. (The default.)

nProhibits the allocation of additional physical extents on the physical volume. The logical volumes that reside on the physical volume can still be accessed, after the volume group has been activated with the vgchange -a y command.

-e MaxPhysicalExtents
Sets the maximum number of physical extents that can be allocated from any of the physical volumes in the volume group. The default is 1016.

-l MaxLogicalVolumes
Sets the maximum number of logical volumes that the volume group is allowed to contain. The default is 255.

-p MaxPhysicalVolumes
Sets the maximum number of physical volumes that the volume group is allowed to contain. The default is 32.

-s PhysicalExtentSize
Sets the number of megabytes in each physical extent, where PhysicalExtentSize is expressed in units of megabytes from 1 through 256. PhysicalExtentSize must be equal to a power of 2 (for example, 1, 2, 4, 8). The default is 1 megabyte.

-v VGDAThis option allows you to specify if a VGDA (Volume Group Descriptor Area) of the volume group has to be stored on the physical volume(s). A VGDA is always stored on the first physical volume specified. This flag impacts only the second, third, and so on, physical volumes specified. VGDA is represented by one of the following:

yAllows the creation of a VGDA on the physical volume. (The default.)

nProhibits the creation of a VGDA on the physical volume.

DESCRIPTION

The vgcreate command creates a new volume group. VolumeGroupName is a symbolic name for the volume group and must be used by all references to it. VolumeGroupName is the path to a directory-entry under /dev which must contain a character special file named group. Except for the group entry, the directory VolumeGroupName should not contain any other entries.

The vgcreate command leaves the volume group in an active state.

Before assigning a physical volume to a volume group, the physical volume has to be created with the pvcreate command.

If vgcreate fails to install the first specified physical volume into the volume group, the volume group is not created. If, for any reason, one of the remaining specified physical volumes cannot be installed into the volume group, an error message is printed, but the installation continues to the end of the list of physical volumes.

EXAMPLES

1.To create a volume group named /dev/my_vg that contains three physical volumes, with extent size set to 2 megabytes, enter:

vgcreate -s 2 /dev/my_vg /dev/hdisk3 /dev/hdisk5 /dev/hdisk6

If the directory /dev/my_vg exists with the character special file group, the volume group will be created.

2.To create a volume group named /dev/user_vg that can contain a maximum of three logical volumes, with extent size set to 8 megabytes, enter:

vgcreate -l 3 -s 8 /dev/user_vg /dev/hdisk3

A new volume group, /dev/user_vg is created with extent size equal to 8 megabytes.

FILES

/usr/sbin/vgcreate
Specifies the command path

ENVIRONMENT NOTES

This section describes system features that are not generic to OSF/1 but that are provided in this OSF/1 implementation.

ULTRIX Compatibility