Note the following limitations of online relayout:

• Log plexes cannot be transformed.

• Volume snapshots cannot be taken when there is an online relayout operation running on the volume.

• 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.

• 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. Relayout is not possible unless you make the layouts of the individual plexes identical.

• Online relayout cannot transform sparse plexes, nor can it make any plex sparse. (A sparse plex is a plex that is not the same size as the volume, or that has regions that are not mapped to any subdisk.)

• The number of mirrors in a mirrored volume cannot be changed using relayout. Instead, use alternative commands, such as the vxassist mirror command.

• Only one relayout may be applied to a volume at a time.