386 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
9.1  Storage migration overview
To migrate data from a storage system to the Storwize V7000, it is necessary to use the 
built-in external virtualization capability. This capability places external connected Logical 
Units (LUs) under the control of the Storwize V7000. After volumes are virtualized, hosts 
continue to access them, but do so through the Storwize V7000, which acts as a proxy.
Consider the following points about the storage migration process:
/SM590000Typically, storage systems divide storage into many Small Computer System Interface LUs 
that are presented to hosts.
/SM590000I/O to the LUs must be stopped and changes made to the mapping of the external storage 
system LUs and to the fabric configuration so that the original LUs are presented directly 
to the Storwize V7000 and not to the hosts anymore. The Storwize V7000 discovers the 
external LUs as unmanaged MDisks.
/SM590000The unmanaged MDisks are imported to the Storwize V7000 as image-mode volumes and 
placed into a temporary storage pool. This storage pool is now a logical container for the 
LUs.
/SM590000Each MDisk has a one-to-one mapping with an image-mode volume. From a data 
perspective, the image-mode volumes represent the LUs exactly as they were before the 
import operation. The image-mode volumes are on the same physical drives of the 
external storage system and the data remains unchanged. The Storwize V7000 is 
presenting active images of the LUs and is acting as a proxy.
/SM590000The hosts must have the storage system multipath device driver removed, and are then 
configured for Storwize V7000 attachment. The Storwize V7000 hosts are defined with 
worldwide port names (WWPNs) or iSCSI Qualified Names (IQNs), and the volumes are 
mapped to the hosts. After the volumes are mapped, the hosts discover the Storwize 
V7000 volumes through a host rescan or reboot operation.
/SM590000IBM Spectrum Virtualize volume mirroring operations are then initiated. The image-mode 
volumes are mirrored to generic volumes. Volume mirroring is an online migration task, 
which means a host can still access and use the volumes during the mirror 
synchronization process.
/SM590000After the mirror operations are complete, the image-mode volumes are removed. The 
external storage system LUs are now migrated and the now redundant storage can be 
decommissioned or reused elsewhere.
Attention: The system does not require a license for its own control and expansion 
enclosures. However, a license is required for each enclosure of any external systems that 
are being virtualized. Data can be migrated from storage systems to your system by using 
the external virtualization function within 45 days of purchase of the system without 
purchase of a license. After 45 days, any ongoing use of the external virtualization function 
requires a license for each enclosure in each external system.
Set the license temporarily during the migration process to prevent messages that indicate 
that you are in violation of the license agreement from being sent. When the migration is 
complete, or after 45 days, reset the license to its original limit or purchase a new license.