Chapter 11. Advanced Copy Services 465
Table 11-7   FlashCopy and remote copy interaction
11.1.20  FlashCopy attributes and limitations
The FlashCopy function in IBM Spectrum Virtualize features the following attributes:
/SM590000The target is the time-zero copy of the source, which is known as FlashCopy mapping 
target.
/SM590000FlashCopy produces an exact copy of the source volume, including any metadata that was 
written by the host operating system, Logical Volume Manager (LVM), and applications. 
/SM590000The source volume and target volume are available (almost) immediately following the 
FlashCopy operation.
/SM590000The source and target volumes must be the same “virtual” size.
/SM590000The source and target volumes must be on the same Storwize V7000 system.
/SM590000The source and target volumes do not need to be in the same I/O Group or storage pool.
/SM590000The storage pool extent sizes can differ between the source and target.
/SM590000The target volumes can be the source volumes for other FlashCopy mappings (cascaded 
FlashCopy). But a target volume can only have one source copy.
/SM590000Consistency groups are supported to enable FlashCopy across multiple volumes at the 
same time.
/SM590000The target volume can be updated independently of the source volume.
/SM590000Bitmaps that are governing I/O redirection (I/O indirection layer) are maintained in both 
nodes of the Storwize V7000 I/O Group to prevent a single point of failure.
/SM590000FlashCopy mapping and Consistency Groups can be automatically withdrawn after the 
completion of the background copy.
/SM590000Thin-provisioned FlashCopy (or Snapshot in the graphical user interface (GUI) use disk 
space only when updates are made to the source or target data, and not for the entire 
capacity of a volume copy.
Component Remote copy primary si te Remote copy secondary site 
FlashCopy
Source
Supported Supported latency: When the 
FlashCopy relationship is in the 
preparing and prepared states, 
the cache at the remote copy 
secondary site operates in 
write-through mode.
This process adds latency to 
the latent remote copy 
relationship. 
FlashCopy
Target
This is a supported combination 
and has the following 
restrictions:
/SM590000Issuing a stop -force 
might cause the remote 
copy relationship to be fully 
resynchronized.
/SM590000Code level must be 6.2.x or 
later.
/SM590000I/O Group must be the 
same.
This is a supported combination 
with the major restriction that 
the FlashCopy mapping cannot 
be copying, stopping, or 
suspended. Otherwise, the 
restrictions are the same as at 
the remote copy primary site.