reducevg Command

AIX Version 4.3 Commands Reference, Volume 4

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

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 Web-based System Manager Volumes application (wsm lvm fast path) to run this command. You could also use the System Management Interface Tool (SMIT) smit reducevg fast path to run this command.

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

To remove physical volume hdisk1 from volume group vg01, enter:
```
reducevg vg01 hdisk1
```
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 4.3 System Management Guide: Operating System and Devices.

Setting up and running Web-based System Management in AIX Version 4.3 System Management Guide: Operating System and Devices.

The System Management Interface Tool (SMIT) Overview in AIX Version 4.3 System Management Guide: Operating System and Devices.

AIX HACMP/6000 Concepts and Facilities.