Chapter 3: DXi4500 Concepts
Data Deduplication Policy
Quantum DXi4500 User’s Guide
25
Data Deduplication Policy
To enable data deduplication when you create a NAS share, select the
Enable Data Deduplication
check box on the
Add NAS Share
page.
(The check box is selected by default.) After the NAS share is created,
you cannot disable data deduplication for the share.
When data deduplication is enabled for a NAS share, there are two data
deduplication policies to consider:
•
Adaptive In-line Data Deduplication (Backup Window Not Defined)
•
Deferred Processing Data Deduplication (Backup Window Defined)
Adaptive In-line Data
Deduplication (Backup
Window Not Defined)
If you do not define a backup window for the NAS share, data
deduplication is running all of the time. Backup data is sent to the
DXi4500 and deduplication is performed on data as it is ingested. Data
deduplication begins when the backup begins.
To use adaptive in-line data deduplication, clear the
Enable Backup
Window
check box on the
Add NAS Share
page.
Note:
The data deduplication setting for OST storage servers is not
configurable. It is always adaptive in-line data deduplication.
Advantages
- The advantage of selecting adaptive in-line data
deduplication is that there is no need to reserve any extra disk space for
the backup, minimizing disk requirements, and replication of new
blocks takes place while the backup is in progress.
Disadvantages
- Because the system resources are always performing
data deduplication while ingest is going on, there are situations in
which the backup window can be negatively affected.
Deferred Processing
Data Deduplication
(Backup Window
Defined)
If you define a backup window for the NAS share, data deduplication is
disabled for a specific time period which can boost ingest speeds and
shorten the backup window. All of the backup data is sent to the
DXi4500 immediately in its raw form without deduplication. After the
backup window is closed and data deduplication is re-enabled, the data
Summary of Contents for DXi4500
Page 18: ...Preface xviii Quantum DXi4500 User s Guide...
Page 22: ...Preface xxii Quantum DXi4500 User s Guide...
Page 34: ...Chapter 1 DXi4500 System Description DXi Advanced Reporting 12 Quantum DXi4500 User s Guide...
Page 56: ...Chapter 3 DXi4500 Concepts Network Segmentation 34 Quantum DXi4500 User s Guide...
Page 146: ...Chapter 6 DXi4500 Status System 124 Quantum DXi4500 User s Guide...
Page 218: ...Appendix A DXi4500 System Specifications 196 Quantum DXi6500 User s Guide...