Data Protection for Exchange supports
different types of backups. The full backup, copy backup, incremental
backup, and differential backup types can be performed with VSS operations.
Data Protection for Exchange backup
types have the following characteristics:
- Full backup (VSS)
- A full backup backs up the specified database, and associated
transaction logs. The Exchange Server deletes the committed log files
after the database, and logs are successfully checked for integrity
and backed up. If the database is not mounted, the backup fails and
the transaction logs are not truncated.
- Copy Backup (VSS)
- A copy backup is similar to a full backup except that transaction
log files are not deleted after the backup. A copy backup is used
to make a full backup of the Exchange Server database without disrupting
any backup procedures that use an incremental or differential backup.
- Incremental Backup (VSS)
- An incremental backup backs up only transaction logs. The Exchange
Server deletes the committed log files after they are successfully
backed up. These log files are not deleted if the backup fails. Restoration
of an Exchange Server database from an incremental backup requires
the following tasks:
- Restore of the last full backup
- Restore of any other incremental backups that are performed between
the full backup and this incremental backup
- Restore of this incremental backup
The log files are not deleted if databases are not mounted.
- Differential Backup (VSS)
- A differential backup backs up transaction logs. The log files
are not deleted. When you run a full backup followed by only differential
backups, the last full backup and the latest differential backup contain
all data that is required to bring the database back to the most recent
state. This type of backup is also called a cumulative incremental backup.
Restoring an Exchange Server database from a differential backup
requires the following tasks:
- Restore of the last full backup
- Restore of this differential backup, but no other differential
backups
When circular logging is enabled, you cannot
use differential or incremental backups. Data loss might occur if
the log wrapped before an incremental or differential backup is finished.
If you choose a backup strategy that involves incremental or differential
backups, you must disable circular logging for the Exchange database
from the Exchange program. See theMicrosoft Exchange
Server documentation for more information about circular logging.