reducevg

reducevg Command



Purpose

Removes physical volumes from a volume group. When all physical volumes
are removed from the volume group, the volume group is deleted.

Syntax

reducevg [ -d ] [ -f ] VolumeGroup PhysicalVolume ...

Description

Attention: You can use the reducevg command while the volume group
is in concurrent mode. However, if you run this command while the
volume group is in concurrent mode and the end result is the deletion
of the volume group, then the reducevg command will fail.

The reducevg command removes one or more physical volumes represented
by the PhysicalVolume parameter from the VolumeGroup. When you remove
all physical volumes in a volume group, the volume group is also removed.
The volume group must be varied on before it can be reduced.

All logical volumes residing on the physical volumes represented by
the PhysicalVolume parameter must be removed with the rmlv command
or the -d flag before starting the reducevg command.

Notes: 

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

2.	Sometimes a disk is removed from the system without first running
reducevg VolumeGroup PhysicalVolume. The VGDA still has this removed
disk in it's memory, but the PhysicalVolume name no longer exists
or has been reassigned. To remove references to this missing disk
you can still use reducevg, but with the Physical Volume ID (PVID)
instead of the disk name: reducevg VolumeGroup PVID

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

smit reducevg

Flags

-d	Deallocates the existing logical volume partitions and then deletes
resultant empty logical volumes from the specified physical volumes.
User confirmation is required unless the -f flag is added.

Attention: The reducevg command with the -d flag automatically deletes
all logical volume data on the physical volume before removing the
physical volume from the volume group. If a logical volume spans multiple
physical volumes, the removal of any of those physical volumes may
jeopardize the integrity of the entire logical volume.

-f	Removes the requirement for user confirmation when the -d flag
is used.

Examples

1.	To remove physical volume hdisk1 from volume group vg01, enter:

reducevg vg01 hdisk1

2.	To remove physical volume hdisk1 and all residing logical volumes
from volume group vg01 without user confirmation, enter the following
command.

Attention: The reducevg command with the -d flag automatically deletes
all logical volume data before removing the physical volume.

reducevg -d -f vg01 hdisk1

The physical volume hdisk1 and all residing logical volumes are removed.

Files

/etc	Directory where the reducevg command resides.

/tmp	Directory where the temporary files are stored and while the
command is running.

Related Information

The extendvg command, rmlv command.

The Logical Volume Storage Overview in AIX Version 4 System Management
Guide: Operating System and Devices.

The System Management Interface Tool (SMIT) Overview in AIX Version
4 System Management Guide: Operating System and Devices.

AIX HACMP/6000 Concepts and Facilities.