chvg

chvg Command



Purpose

Sets the characteristics of a volume group.

Syntax

chvg [ -a AutoOn { n | y } ] [ -c ] [ -Q { n | y } ] [-u 
] [ -x { n | y } ] VolumeGroup

Description

The chvg command specifies whether or not the volume group is automatically
activated during the system startup. If there is a volume group that
is infrequently used, you may not want it activated at system startup
because it uses kernel resources (memory).

Note:	To use this command,  either have root user authority
or be a member of the system group.

You can use the System Management Interface Tool (SMIT) to run this
command. To use SMIT, enter:

smit chvg

Flags

-a AutoOn	Determines if the volume group is automatically activated
during system startup. The AutoOn variable can be either of the following:

n	The volume group is not automatically activated during system startup.

y	The volume group is automatically activated during system startup.

-c	Changes the volume group into a Concurrent Capable volume group.
Howerver, the volume group must be varied on in non-concurrent mode
for this command to take effect. This flag only applies to AIX Version
4.2 or later.

Note:	You can tranform a non-concurrent volume group into a Concurrent
Capable volume group. However, you can not transform a Concurrent
Capable volume group into a non-concurrent capable volume group.

-Q 	Determines if the volume group is automatically varied off after
losing its quorum of physical volumes. The default value is yes. The
change becomes effective the next time the volume group is activated.

n	The volume group stays active until it loses all of its physical
volumes.

y	The volume group is automatically varied off after losing its quorum
of physical volumes.

Note:	Run the bosboot or savebase command after the chvg -Q n or chvg
-Q y command to update the boot image.

-u	Unlocks the volume group. This option is provided if the volume
group is left in a locked state by abnormal termination of another
LVM operation (such as the command core dumping, or the system crashing).

Note:	Before using the -u flag, make sure that the volume group is
not being used by another LVM command.

-x	Changes the mode which the Concurrent Capable volume group is varied
on. The volume group must be varied on in non-concurrent mode for
this command to take effect. This flag only applies to AIX Version
4.2 or later.

y	autovaryon the volume group in concurrent mode.

n	autovaryon the volume group in non-concurrent mode.

Note:	If the volume group is not created Concurrent Capable, this
command has no effect on the volume group.

In order for this auto-varyon into concurrency of the volume group
to take effect,  enter the following line into the /etc/inittab"
file:

rc_clvmv:2:wait:/usr/sbin/clvm_cfg 2>&1

Attention: This entry must be added after the entry used to initiate
srcmstr.

Examples

To cause volume group vg03 to be automatically activated during system
startup, enter:

chvg -a y vg03

Files

/usr/sbin	Directory where the chvg command resides.

Related Information

Commands: bosboot, lsvg, mkvg, savebase, varyonvg.

The Logical Volume Storage Overview in AIX Version 4 System Management
Guide: Operating System and Devices explains the Logical Volume Manager,
physical volumes, logical volumes, volume groups, organization, ensuring
data integrity, and allocation characteristics.

The System Management Interface Tool (SMIT): Overview in AIX Version
4 System Management Guide: Operating System and Devices explains the
structure, main menus, and tasks that are done with SMIT.

AIX HACMP/6000 Concepts and Facilities.