Contents
1 Introduction
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13
2 Concepts
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15
Disk-based Backup and Virtual Tape Libraries
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15
Problems Addressed by Virtual Tape Libraries
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15
Integration of Disk in Data Protection Processes
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15
Where Virtual Tape Fits in the Big Picture
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16
HP VLS and D2D Portfolio
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16
Typical VLS Environments
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17
Typical D2D Environments
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17
What are the Alternatives?
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18
Physical Tape
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18
NAS
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18
Application-based Disk Backup
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18
Business Copy
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19
Deduplication
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20
Introduction
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20
HP StorageWorks Deduplication Solutions
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20
Deduplication Ratios
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21
Target-based Deduplication
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22
Tape Oversubscription
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23
Replication
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23
Introduction to Replication
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23
HP StorageWorks Replication Solutions
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24
Replication Deployment Options
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26
Backup Application Interaction with Replication
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28
Replication Limitations
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29
3 Backup Solution Design Considerations
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31
Analyze the Existing Environment
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31
Consider How you Want to Back Up your Data to the VLS or D2D
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31
Consider How you Want to Copy the Backup Data to an Off-site Location
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33
Consider Speed and Ease of the Restore as well as the Backup
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33
Single Library vs. Multiple Libraries
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33
Single Library
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33
Benefits of Single Library Systems
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34
Considerations for Single Library Systems
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34
Multiple Library
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35
Benefits of Multiple Library Systems
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35
Multiplexing, Multistreaming, and Multipathing
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36
Multiplexing
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36
Multistreaming
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36
Multipathing
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36
Blocksize and Transfer Size
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37
HP StorageWorks VLS and D2D Solutions Guide
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