vgcreate(1M) — Series 800 Only

NAME

vgcreate − create a volume group

SYNOPSIS

/etc/vgcreate [-x extensibility] [-e max_physical_extents] [-l max_logical_vols] [-p max_physical_vols] [-s physical_extent_size] [-g physical_vol_group_name] volume_group_name physical_volume_path ...

DESCRIPTION

vgcreate creates a new volume group. volume_group_name is a symbolic name for the volume group and must be used in all references to it. volume_group_name 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 volume_group_name should not contain any other entries.

vgcreate leaves the volume group in an active state.

Before assigning a physical volume to a volume group, the physical volume has to be created using the pvcreate command (see pvcreate(1M)).

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 until the end of the list of physical volumes.

Options and Arguments

-x extensibility Set the allocation permission for adding physical extents on the physical volumes specified by the physical_volume_path parameter. extensibility can have either of the following values:

y (default) Allow allocation of additional physical extents on the physical volume.

n Prohibit allocation of additional physical extents on the physical volume. Logical volumes residing on the physical volume can still be accessed after the volume group has been activated by the vgchange -a y command.

-e max_physical_extents
Set maximum number of physical extents that can be allocated from any of the physical volumes in the volume group. Default value for max_physical_extents is 1016. However, if the size of any physical volume exceeds 1016 times the physical_extent_size, the default value for max_physical_extents is adjusted to match the physical volume size. The maximum number of physical extents can be a value ranging from 1 through 65535.

-l max_logical_vols
Set maximum number of logical volumes that the volume group is allowed to contain. Default value for max_logical_vols is 255. The maximum number of logical volumes can be a value ranging from 1 through 255.

-p max_physical_vols
Set maximum number of physical volumes that the volume group is allowed to contain. Default value for max_physical_vols is 16. The maximum number of physical volumes can be a value ranging from 1 through 255.

−s physical_extent_size
Sets the number of megabytes in each physical extent, where physical_extent_size is expressed in units of Mbytes from 1 through 256. physical_extent_size must be equal to a power of 2 (1, 2, 4, 8, etc.). Default value for physical_extent_size is 4 Mbytes.

−g physical_vol_group_name
Create a new physical volume group with the name physical_vol_group_name. All physical volumes specified in the physical_volume_path parameter become a member of the newly created physical volume group.

The physical volume group information is stored in an ASCII file /etc/lvmpvg. The file can be edited to create a physical volume group instead of using the vgcreate command. However, ensure that the physical volumes to be used have already been installed in the volume group prior to creating the physical volume group.

The physical volume group name must be unique within a volume group although identical physical volume group names can appear in different volume groups (see lvmpvg(4) for format details).

EXTERNAL INFLUENCES

Environment Variables

LANG determines the language in which messages are displayed.

If LANG is not specified or is set to the empty string, a default of "C" (see lang(5)) is used instead of LANG.

If any internationalization variable contains an invalid setting, vgcreate behaves as if all internationalization variables are set to "C". See environ(5).

EXAMPLES

Create a volume group named /dev/vg00 containing two physical volumes with extent size set to 2 Mbytes. If directory /dev/vg00 exists with the character special file group, the volume group is created:

vgcreate -s 2 /dev/vg00 /dev/dsk/c1d0s2 /dev/dskc2d0s2

Create a volume group named /dev/vg01 that can contain a maximum of three logical volumes, with extent size set to 8 Mbytes:

vgcreate −l 3 −s 8 /dev/vg01 /dev/dsk/c4d0s2

Create a volume group named /dev/vg00 and a physical volume group named PVG0 with two physical volumes:

vgcreate −g PVG0 /dev/vg00 /dev/dsk/c1d0s2 /dev/dsk/c2d0s2

REMARKS

It is not possible to create a volume group that contains both HP-IB devices and devices using another type of interface.

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