VERITAS Volume Manager 3.5 Administrator's Guide (September 2002)

Chapter 1, Understanding VERITAS Volume Manager

Online Relayout

Transformations are not supported for the following objects:

◆ Log plexes.

◆ Volume snapshot when there is an online relayout operation running on the volume.

Also note the following limitations:

◆ Online relayout cannot create a non-layered mirrored volume in a single step. It

always creates a layered mirrored volume even if you specify a non-layered mirrored

layout, such as mirror-stripe or mirror-concat. Use the vxassist convert

command to turn the layered mirrored volume that results from a relayout into a

non-layered volume. See “Converting Between Layered and Non-Layered Volumes”

on page 224 for more information.

◆ Online relayout can be used only with volumes that have been created using the

vxassist command or the VERITAS Enterprise Administrator (VEA).

◆ The usual restrictions apply for the minimum number of physical disks that are

required to create the destination layout. For example, mirrored volumes require at

least as many disks as mirrors, striped and RAID-5 volumes require at least as many

disks as columns, and striped-mirror volumes require at least as many disks as

columns multiplied by mirrors.

◆ To be eligible for layout transformation, the plexes in a mirrored volume must have

identical stripe widths and numbers of columns.

◆ Online relayout involving RAID-5 volumes is not supported for shareable disk

groups in a cluster environment.

◆ Online relayout cannot transform sparse plexes, nor can it make any plex sparse. (A

sparse plex is not the same size as the volume, or has regions that are not mapped to

any subdisk.)

Supported Relayout Transformations for Unmirrored Stripe, and Layered Striped-Mirror Volumes

Relayout to From stripe, or stripe-mirror

concat Yes.

concat-mirror Yes.

mirror-concat No. Use vxassist convert after relayout to concatenated-mirror volume

instead.

mirror-stripe No. Use vxassist convert after relayout to striped-mirror volume instead.

raid5 Yes. The stripe width and number of columns may be changed.

stripe Yes. The stripe width or number of columns must be changed.

stripe-mirror Yes. The stripe width or number of columns must be changed.