HP Data Protector A.06.11 Integration Manual page 54

DP snapshot
Snapshot mode: single
A full backup in the Single mode progresses in the same way as a full backup in the
Disabled mode, with the exception that the DP snapshot is not removed at the end
(you end up with one DP snapshot). A subsequent differential backup is shown in the
following figure.
54 Integrating VMware Virtual Infrastructure and Data Protector
A rectangle denoted by DP snapshot represents a process (snapshot
operation triggered by Data Protector). This process closes the current
active state to become a read-only file. At the same time, it creates a new
delta file, which becomes the active state. The active state is denoted by
round corners.