HP-UX Reference (11i v3 07/02) - 1M System Administration Commands N-Z (vol 4)
v
vgcreate(1M) vgcreate(1M)
-f 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 pvcreate -f.) 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.
-g pvg_name 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,
/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).
-l max_lv Set the maximum number of logical volumes that the volume group is allowed to
contain. The default value for max_lv is 255. The maximum number of logical
volumes can be a value in the range 1 to 255.
-p max_pv Set the maximum number of physical volumes that the volume group is allowed
to contain. The default value for max_pv is 16. The maximum number of physi-
cal volumes can be a value in the range 1 to 255.
-s pe_size 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
4 (four
megabytes).
-x extensibility 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:
y Allow allocation of additional physical extents on the physical volume. This
is the default.
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.
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 simultaneously.
There is a new feature introduced in the Mass Storage Subsystem on this version of HP-UX that also sup-
ports 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:
• Only the legacy device special file naming convention is used in the volume group configuration.
• The
scsimgr command is used to disable the Mass Storage Subsystem multipath behavior.
EXTERNAL INFLUENCES
Environment Variables
LANG determines the language in which messages are displayed.
If LANG 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)).
HP-UX 11i Version 3: February 2007 − 2 − Hewlett-Packard Company 627