User guide

Introduction to AppAssure 5 | 21
The typical disk layout of a server consists of the operating system, application, and
data. In most environments, the administrators often use a common flavor of the
server and desktop operating system across multiple systems for effective
deployment and management. When backup is performed at the block level across
multiple machines at the same time, it provides a more granular view of what is in
the backup and what is not, irrespective of the source. This data includes the
operating system, the applications, and the application data across the environment.
Figure 1. True Global Deduplication
AppAssure 5 performs target-based inline data deduplication. This means that the
snapshot data is transmitted to the Core before it is deduplicated. Inline data
deduplication simply means the data is deduplicated before it is committed to disk.
This is very different from at-source or post-process deduplication, where the data
is deduplicated at the source before it is transmitted to the target for storage, and in
post-process the data is sent raw to the target where it is analyzed and deduplicated
after the data has been committed to disk. At-source deduplication consumes
precious system resources on the machine whereas the post-process data
deduplication approach needs all the requisite data on disk (a greater initial capacity
overhead) before commencing the deduplication process. On the other hand, inline
data deduplication does not require additional disk capacity and CPU cycles on the
source or on the Core for the deduplication process. Lastly, conventional backup
applications perform repetitive full backups every week, while AppAssure performs
incremental block-level backups of the machines forever. This incremental forever
approach in tandem with data deduplication helps to drastically reduce the total
quantity of data committed to the disk with a reduction ratio of as much as 80:1.