460 Implementing the IBM Storwize V7000 with IBM Spectrum Virtualize V8.2.1
Table 11-6   Mapping events
Overview of a FlashCopy sequence of events: The following tasks show the FlashCopy 
sequence:
1. Associate the source data set with a target location (one or more source and target 
volumes).
2. Create a FlashCopy mapping for each source volume to the corresponding target 
volume. The target volume must be equal in size to the source volume.
3. Discontinue access to the target (application dependent).
4. Prepare (pre-trigger) the FlashCopy:
a. Flush the cache for the source.
b. Discard the cache for the target.
5. Start (trigger) the FlashCopy:
a. Pause I/O (briefly) on the source.
b. Resume I/O on the source.
c. Start I/O on the target.
Mapping event Description
Create A FlashCopy mapping is created between the specified source volume 
and the specified target volume. The operation fails if any one of the 
following conditions is true:
/SM590000The source volume is a member of 256 FlashCopy mappings.
/SM590000The node has insufficient bitmap memory.
/SM590000The source and target volumes are different sizes.
Prepare The prestartfcmap or prestartfcconsistgrp command is directed to a 
Consistency Group for FlashCopy mappings that are members of a 
normal Consistency Group or to the mapping name for FlashCopy 
mappings that are stand-alone mappings. The prestartfcmap or 
prestartfcconsistgrp command places the FlashCopy mapping into the 
Preparing state.
The prestartfcmap or prestartfcconsistgrp command can corrupt any 
data that was on the target volume because cached writes are discarded. 
Even if the FlashCopy mapping is never started, the data from the target 
might be changed logically during the act of preparing to start the 
FlashCopy mapping.
Flush done The FlashCopy mapping automatically moves from the preparing state 
to the prepared state after all cached data for the source is flushed and 
all cached data for the target is no longer valid.