Chapter 2. System overview 17
This option has two variations:
 Space-efficient source and target with background copy
Copies only the allocated space.
 Space-efficient target with no background copy
Copies only the space that is used for changes between the source and target, and 
is referred to as a snapshot.
This function can be used with multitarget, cascaded, and incremental FlashCopy.
– Consistency groups
Consistency groups address the issue where application data is on multiple volumes. 
By placing the FlashCopy relationships into a consistency group, commands can be 
issued against all of the volumes in the group. This action provides a consistent 
point-in-time copy of all of the data, even if it is on a physically separate volume.
FlashCopy mappings can be members of a consistency group, or they can be operated 
in a stand-alone manner, not as part of a consistency group. FlashCopy commands 
can be issued to a FlashCopy consistency group, which affects all FlashCopy 
mappings in the consistency group, or to a single FlashCopy mapping if it is not part of 
a defined FlashCopy consistency group.
/SM590000Metro Mirror
Provides a synchronous remote mirroring function up to approximately 300 km 
(186.4 miles) between sites. Because the host I/O only completes after the data is cached 
at both locations, performance requirements might limit the practical distance. Metro 
Mirror provides fully synchronized copies at both sites with zero data loss after the initial 
copy is completed. Metro Mirror can operate between multiple IBM Storwize systems and 
IBM SAN Volume Controllers.
/SM590000Global Mirror
Provides a long-distance asynchronous remote mirroring function up to approximately 
8,000 km (4,971 miles) between sites. With Global Mirror, the host I/O completes locally 
and the changed data is sent to the remote site later. This feature maintains a consistent 
recoverable copy of data at the remote site, which lags behind the local site. Global Mirror 
can operate between multiple IBM Storwize systems and IBM SAN Volume Controllers.
/SM590000External virtualization
IBM Storwize V7000 provides a data migration function that can be used to import external 
storage systems into the IBM Storwize V7000 system. The following tasks can be 
accomplished:
– Move volumes nondisruptively onto a newly installed storage system.
– Move volumes to rebalance a changed workload.
– Migrate data from other back-end storage to IBM Storwize V7000-managed storage.
/SM590000Software Encryption
IBM Storwize V7000 Gen2 and IBM Storwize Gen2+ provide optional encryption of 
data-at-rest functionality, which protects against the potential exposure of sensitive user 
data and user metadata that is stored on discarded, lost, or stolen storage devices. 
Encryption can only be enabled and configured on enclosures that support encryption.
Starting with IBM Spectrum Virtualize V7.6, IBM Spectrum Virtualize offers 
software-enabled encryption (hardware encryption was introduced in V7.4), which 
includes encryption of internal or external storage. Encryption keys now can be stored 
either on USB flash drives, IBM Security Key Lifecycle Manager server, or both.