vgcreate(1M)															      vgcreate(1M)

NAME

       vgcreate - create LVM volume group

SYNOPSIS

       autobackup] extensibility] max_pe] max_lv] max_pv] pe_size] pvg_name] vg_name pv_path ...

       pe_size vg_size autobackup] extensibility] pvg_name] vg_name pv_path ...

       pe_size | vg_size}

DESCRIPTION

       The  command without the option creates a new volume group.  vg_name is a symbolic name for the volume group and must be used in all refer-
       ences to it.  vg_name is the path to a directory entry under that must contain a character special file named Except  for  the  entry,  the
       vg_name	directory  should be empty.  A user may explicitly create the vg_name directory and the file before creating the volume group.	If
       absent, the command will automatically create the directory and the file, assigning the minor number.  If the file  is  automatically  cre-
       ated, any available minor number may be assigned to the file.

       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 command (see pvcreate(1M)).

       If 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  con-
       tinues until the end of the list of physical volumes.

       The  command  with the option displays information which may be useful in deciding on parameters for use in creating a volume group version
       2.0 and higher.

       The option (only for volume groups versions 2.0 and higher) displays the relationship between physical extent size  (pe_size)  and  maximum
       volume  group size (vg_size).  See lvm(7) for more on this topic.  A pe_size or a vg_size must be supplied on the command line.	If pe_size
       is specified, then the maximum volume group size which can be created using that  extent  size  is  displayed  using  the  suffix  notation
       explained in the description of the option.  If the vg_size is specified then the minimum extent size required to support the given maximum
       volume group size is displayed in megabytes.

   Options and Arguments
       recognizes the following options and arguments:

	      Specify the version of the volume group.
				  Currently only and are supported.  Different versions represent significant changes in  LVM  software  and  data
				  layout  and  may  have  compatibility implications when volume groups are shared or moved from system to system.
				  See lvm(7) for more details.	The default version is 1.0.

	      pv_path		  The block device path name of a physical volume that will be assigned to the new volume group.

				  On PA-RISC systems, pv_path should be the path name for the whole disk.  For HP Integrity system  boot  physical
				  volumes,  pv_path  should be the path name for the disk section containing the HP-UX partition (see model(1) and
				  getconf(1)).	For HP Integrity system non-boot physical volumes, pv_path can be the path name for the whole disk
				  or the disk section containing the HP-UX partition.

				  You  can  specify  physical volume links pv-links for a physical volume providing different paths that reference
				  the same physical volume in the pv_path list.  The order in which the paths are listed is important.	The  first
				  path	becomes  the to the physical volume, and the second becomes an to the physical volume.	The is the default
				  path used to access the physical volume.  (see section).  If the becomes unavailable, LVM automatically switches
				  to  the  to  access  the  physical volume.  Currently, LVM supports a maximum of 8 paths to a physical volume (7
				  alternate and one primary).

	      vg_name		  The path name of a subdirectory of the directory.  vg_name must be empty except for  a  character  special  file
				  named Typically, this directory name is in the form where NN numbers sequentially from

	      Set automatic backup for this invocation of this command.
				  autobackup can have one of the following values:

				  Automatically back up configuration changes made to the volume group.
					 This is the default.

					 After this command executes, the command (see vgcfgbackup(1M)) is executed for the volume group.

				  Do not back up configuration changes this time.

	      Only applicable to volume groups version 1.0.
				  Set  the maximum number of physical extents that can be allocated from any of the physical volumes in the volume
				  group.  The default value for max_pe is However, if the size of any physical volume exceeds times  the  pe_size,
				  the  default	value  for  max_pe  is adjusted to match the physical volume size.  The maximum number of physical
				  extents can be a value in the range 1 to 65535.

	      Only applicable to volume groups version 1.0.
				  This option will force a volume group to be created with a physical volume which has alternate block(s)  already
				  allocated, (that is, this physical volume was not initialized using This option should be used with extreme cau-
				  tion.  If the volume group to be created has a different physical extent size, the alternate block(s)  might	be
				  inside the user data area.  Potential data corruption could occur.

	      Create a new physical volume group with the name
				  pvg_name.  All physical volumes specified in the pv_path parameter become a member of the newly created physical
				  volume group.

				  The physical volume group information is stored in an ASCII file, The file can be edited to  create  a  physical
				  volume  group  instead  of using the 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).

	      Only applicable to volume groups version 1.0.
				  Set  the  maximum  number of logical volumes that the volume group is allowed to contain.  The default value for
				  max_lv is The maximum number of logical volumes can be a value in the range 1 to 255.

	      Only applicable to volume groups version 1.0.
				  Set the maximum number of physical volumes that the volume group is allowed to contain.  The default	value  for
				  max_pv is The maximum number of physical volumes can be a value in the range 1 to 255.

	      Sets the number of megabytes in each physical extent, where
				  pe_size  is  expressed  in units of megabytes (MB) in the range 1 to 256.  pe_size must be equal to a power of 2
				  (1, 2, 4, 8, etc.).  The default value for pe_size is (four megabytes) for volume groups version 1.0.  For  vol-
				  ume  groups  versions  2.0  and higher, this is a required parameter.  See lvm(7) for more information on extent
				  sizes on volume groups versions 2.0 and higher.

	      Set the allocation permission for adding physical extents
				  on the physical volumes specified by the pv_path parameter.  extensibility can have one of the following values:

				  Allow allocation of additional physical extents on the physical volume.
					 This is the default.

				  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 command.

	      Only applicable to volume groups versions 2.0 and 2.1.
				  Sets	the  maximum  size of the volume group.  The maximum size is the total size of all physical extents in the
				  volume group.  The unit for is specified as a suffix.  The recognized values for  the  suffix  are  (megabytes),
				  (gigabytes),	(terabytes),  and  (petabytes).   If no suffix is supplied, then (megabytes) is assumed.  A of 512
				  terabytes would be specified as 512t.  Only whole numbers are accepted.  The maximum supported vg_size is 2p.

				  If the product of the physical extent size and the total number of physical extents  for  the  physical  volumes
				  specified  on  the command line is greater than the value specified, then vg_size is upgraded to take account of
				  this size and an informational message is issued.

	      Only applicable to volume groups versions 2.0 and higher.
				  Either or must be supplied.  This option will display the maximum VG size based on  the  given  physical  extent
				  size	option)  or  minimum physical extent size based on the max VG size option).  The output will be in where x
				  and y are determined by or See the section in lvm(7) for more information.

   Alternate Links (PVLinks)
       In this release of HP-UX, LVM continues to support Alternate Links to a device to allow continued access to the device, if the primary link
       fails.	This  multiple link or multipath solution increases data availability, but does not allow the multiple paths to be used simultane-
       ously.

       There is a new feature introduced in the Mass Storage Subsystem on this version of HP-UX that also supports multiple paths to a device  and
       allows access to the multiple paths simultaneously.  The Mass Storage Subsystem will balance the I/O load across the valid paths.  This new
       multi-path behavior is enabled and disabled through the use of the scsimgr command.  See scsimgr(1M) for details.

       It is no longer required or recommended to configure LVM with alternate links.  However, it is possible to  maintain  the  traditional  LVM
       behavior.  To do so, both of the following criteria must be met:

	      o Only the legacy device special file naming convention is used in the volume group configuration.

	      o The command is used to disable the Mass Storage Subsystem multipath behavior.

EXTERNAL INFLUENCES

   Environment Variables
       determines the language in which messages are displayed.

       If is not specified or is null, it defaults to "C" (see lang(5)).

       If any internationalization variable contains an invalid setting, all internationalization variables default to "C" (see environ(5)).

EXAMPLES

       Create a volume group version 1.0 named containing two physical volumes with extent size set to 2 MB, from scratch.

	      Initialize the disks using

	      Create a volume group version 1.0.

	    or

	      The  vg_name directory and group file will be created automatically.  Optionally, these files can be created before doing the vgcre-
	      ate, as follows:

	      The minor number for the group file should be unique among all the volume groups on the system.  It has the format  0xNN0000,  where
	      NN runs from to

	      If the file is automatically created, any available minor number may be assigned to the group file.

	      Create a volume group version 1.0 named that can contain a maximum of three logical volumes, with extent size set to 8 MB:

	      Create a volume group version 1.0 named and a physical volume group named with two physical volumes:

	      Using  the  feature to create a volume group version 1.0 named with a physical volume that can be referenced by two different paths.
	      and refer to the same physical volume, accessed via different controller hardware paths.	In this example, becomes the to the physi-
	      cal volume.  becomes an to the physical volume.

       Create a volume group version 2.0 named with 2 physical volumes, an extent size of 256 megabytes and a maximum total size of 1 petabyte.

	      Initialize the disks using pvcreate

	      Create the volume group version 2.0.

	      The directory and file will be created automatically.  Optionally, these files can be created before doing the as follows:

	      Notice  that  the major number for a volume group version 2.0 or higher is 128 while the major number for a volume group version 1.0
	      is 64.  Also, the volume group number occupies the high order 12 bits of the minor number rather than the high order 8  bits  as	in
	      volume groups version 1.0.

	      Create a volume group version 2.0 of size comparable to a volume group version 1.0 created with and on an already initialized disk.

	      First calculate the appropriate vg_size parameter as follows: (in megabytes) Now create the volume group version 2.0.

	      Display the minimum extent size required to create a 512 terabyte volume group version 2.0.

SEE ALSO

       getconf(1),  model(1),  idisk(1M),  lvmadm(1M),	pvcreate(1M),  scsimgr(1M), vgchange(1M), vgdisplay(1M), vgextend(1M), vgreduce(1M), envi-
       ron(5), lang(5), intro(7), lvm(7).

																      vgcreate(1M)