The FlashBackup cache partition may have run out of space
In that case, the cache partition may not be large enough for the backup requirements.
If the cache partition is full, messages such as the following appear in the system log:
WARNING: sn_alloccache: cache /dev/vx/rdsk/flash1dg/f full - all
snaps using this cache are now unusable
WARNING: sn_failsnap: snapshot id 5 failed error 28Specify a larger cache partition, or designate additional cache partitions in the list.