Acronis Backup for Windows Server Essentials - User Guide - Manual (Page 231)

231 Copyright © Acronis International GmbH, 2002-2014
Back up a typical machine before backing up several machines with similar contents
When backing up several machines with similar contents, it is recommended that you back up one
machine first and wait until the end of the backed-up data indexing. After that, the other machines
will be backed up faster owing to the efficient deduplication. Because the first machine's backup has
been indexed, most of the data is already in the deduplication data store.
Back up different machines at different times
If you back up a large number of machines, spread out the backup operations over time. To do this,
create several backup plans with various schedules.
Use fast cataloging
Indexing of a backup starts after its cataloging has been completed. To reduce the overall time
required for backup processing, switch automatic cataloging (p. 108) to the fast mode. You can start
full cataloging manually outside of the backup window.
Configure alert notifications
It is recommended that you configure the "Vaults" alert notification (p. 389) in the management
server options. This can help you to promptly react in out-of-order situations. For example, a timely
reaction to a "There is a vault with low free space" alert can prevent an error when next backing up
to the vault.
7.5.7.5 Deduplication restrictions
Common restrictions
Deduplication cannot be performed if you protected the archive with a password. Data blocks of
password-protected archives are stored in the backups as they would be in a non-deduplicating
vault.
If you want to protect an archive while still allowing it to be deduplicated, leave the archive
non-password-protected and encrypt the deduplicating vault itself with a password. You can do this
when creating the vault.
Disk-level backup
Deduplication of disk blocks is not performed if the volume's allocation unit size—also known as
cluster size or block size—is not divisible by 4 KB.
Tip: The allocation unit size on most NTFS and ext3 volumes is 4 KB. This allows for block-level deduplication.
Other examples of allocation unit sizes allowing for block-level deduplication include 8 KB, 16 KB, and 64 KB.
File-level backup
Deduplication of a file is not performed if the file is encrypted and the In archives, store encrypted
files in decrypted state check box in the backup options is cleared (it is cleared by default).
Deduplication and NTFS data streams
In the NTFS file system, a file may have one or more additional sets of data associated with it—often
called alternate data streams.
When such file is backed up, so are all its alternate data streams. However, these streams are never
deduplicated—even when the file itself is.