GLYPH<SM590000> In a reverse FlashCopy, the grain size of all the FlashCopy mappings that participate must be the same. 

GLYPH<SM590000> No FlashCopy mapping can be added to a consistency group while the FlashCopy mapping status is Copying . 

GLYPH<SM590000> No FlashCopy mapping can be added to a consistency group while the consistency group status is Copying . 

GLYPH<SM590000> The use of Consistency Groups is restricted when using Cascading FlashCopy. A Consistency Group serves the purpose of starting FlashCopy mappings at the same point in time. Within the same  Consistency Group, it is not possible to have mappings with these conditions: 

– The source volume of one mapping is the target of another mapping. 

– The target volume of one mapping is the source volume for another mapping. 

These combinations are not useful because within a Consistency Group, mappings cannot be established in a certain order. This limitation renders the content of the target volume undefined. For instance, it is not possible to determine whether the first mapping was established before the target volume of the first mapping that acts as a source volume for the second mapping. 

Even if it were possible to ensure the order in which the mappings are established within a Consistency Group, the result is equal to Multi Target FlashCopy (two volumes holding the same target data for one source volume). In other words, a cascade is useful for copying volumes in a certain order (and copying the changed content targets of FlashCopies), rather than at the same time in an undefined order (from within one single Consistency Group). 

GLYPH<SM590000> Both source and target volumes can be used as primary in a Remote Copy relationship. For more details about the FlashCopy and the Remote Copy possible interactions see “Interaction between Remote Copy and FlashCopy” on page 227. 

## FlashCopy presets 

The IBM Spectrum Virtualize/Storwize GUI interface provides three FlashCopy presets (Snapshot, Clone, and Backup) to simplify the more common FlashCopy operations. Figure 5-9 on page 195 shows the preset selection panel in the GUI. 

