Product Overview
How Does AutoBackup Work?
This section describes the following five factors, which are fundamental to the way
that backup is implemented on HP SureStore AutoBackup.
Baseline and incremental backups
Use of a SQL database
Redundant file elimination
Compression
Load balancing
Baseline and Incremental
Backups
When clients carry out the first backup operation, they carry out a "baseline" backup,
which writes the full amount of data to the appliance hard disk. Subsequent backups
only write the actual portions of individual files that have changed since the last
backup. So, although a full baseline backup may take 40 minutes or so, subsequent
backups should only take a few minutes. This is termed block-level incremental
backups.
This approach has two major advantages over magnetic tape and standard Explorer
copy file actions. It keeps network traffic and storage space requirements low and
allows versioning. Clients can restore the latest or an earlier version of a particular
file according to backup date.
Note: As HP SureStore AutoBackup is designed for relatively short-term file restore
rather than long-term archiving, earlier versions of a file are not kept indefinitely, but
are overwritten after a specified retention period (normally one month). Any files
that are deleted on the client's PC will also be deleted on the appliance after a
specified time. See
Retention Limit
for further details.
How Does It Work?
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