HP XP Array Manager Software - Manual (Page 417)

Restoring by using transaction logs (Roll-forward)
When backup data on Exchange Server is restored, the database returns to the state it was in at the
time of the backup. If the transaction logs from when the backup was executed up until when the
restoration command was executed are stored on the primary volume, the transaction logs can be
rolled forward by specifying the
-recovery option. In this case, by applying the transaction logs
after backup, the database can be recovered to the state it was in immediately before the error
occurred.
The procedure for using the transaction logs of Exchange Server to restore backup data by using
roll-forward is described below. The explanations in this section use operation examples for Exchange
Server 2007.
The figure below shows a flow of operation using transaction logs.
Figure 120 Flow of operation using transaction logs
In the figure above, after the database is backed up from the primary volume to the secondary volume
at point A, the database is updated at point B. If an error occurs in a data file on the primary volume
at point C and then the database is restored from the secondary volume to the primary volume, the
database returns to the state it was in at point A. In this case, if the transaction logs from when the
backup was executed up until when the restoration command was executed are stored on the primary
Application Agent CLI User Guide 417