Managed Mode Volumes - IBM Storwize V5010 Manual

IBM Spectrum Virtualize also supports the reverse process, in which a managed mode
volume can be migrated to an image mode volume. If a volume is migrated to another MDisk,
it is represented as being in managed mode during the migration, and is only represented as
an image mode volume after it reaches the state where it is a straight-through mapping.
An image mode MDisk is associated with exactly one volume. If the (image mode) MDisk is
not a multiple of the MDisk Group's extent size, the last extent is partial (not filled). An image
mode volume is a pass-through one-to-one map of its MDisk. It cannot be a quorum disk and
it does not have any metadata extents that are assigned to it from the IBM Spectrum
Virtualize system. Managed or image mode MDisks are always members of a storage pool.
It is a preferred practice to put image mode MDisks in a dedicated storage pool and use a
special name for it (for example, Storage Pool_IMG_xxx). The extent size that is chosen for
this specific storage pool must be the same as the extent size into which you plan to migrate
the data. All of the IBM Spectrum Virtualize copy services functions can be applied to image
mode disks. See Figure 6-2.
Figure 6-2 Image mode volume versus striped volume

6.1.2 Managed mode volumes

Volumes operating in managed mode provide a full set of virtualization functions. Within a
storage pool, the IBM Spectrum Virtualize supports an arbitrary relationship between extents
on (managed mode) volumes and extents on MDisks. Each volume extent maps to exactly
one MDisk extent.
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Implementing the IBM Storwize V5000 Gen2 with IBM Spectrum Virtualize V8.1