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Step 2
Use HP D2D Web
Management Interface to
copy to tape drive.
Step 1
Use backup application on
host to write to cartridge.
HP StorageWorks D2D Backup System
Library
HP StorageWorks D2D Backup System
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2
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8
Library
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Physical
Tape Drive
Cartridge
Figure 55 Cartridge copy
Why use the Copy functionality?
Copy creates two instances of the same cartridge; one stored on the HP D2D, the other on physical
tape. Logically these are the same cartridge and the backup application has no awareness that there
are two copies. If data from this cartridge is required for restore, the backup application will always
restore the data from the HP D2D if it is available. The physical cartridge is, therefore, an additional
copy that will be required only if the HP D2D is not available.
When would Copy be used?
Cartridge copies are likely to be appropriate when the user wishes to use the HP D2D Backup System
for all foreseeable restore processes but requires an additional offsite copy for insurance or data
security purposes. This may mean that weekly, monthly and yearly cartridges are copied. Weekly
and monthly physical cartridges may be rotated; the cartridges on the HP D2D Backup System are
overwritten after a period of time. Yearly cartridges may be kept indefinitely. Clear labeling of the
cartridges in this case is essential because the backup application may overwrite the cartridge on the
HP D2D Backup System and, therefore, lose any knowledge of the existence of the physical tape
cartridge.
When is it necessary to restore from a copied cartridge?
There are three situations where it may be necessary to restore from the copied cartridge:
• The cartridge stored in the library device on the HP D2D is overwritten (accidentally) by the backup
application.
The backup application database is updated to reflect the new contents of the cartridge
and all knowledge of the old data is lost. If the backup administrator becomes aware that this has
happened, it is possible to import the physical cartridge back into the HP D2D System, from where
its data can be "imported" back into the application database for restore, if required. In this case,
because the backup application has overwritten the database entry for the cartridge, some external
knowledge of what is on the copied cartridge is required in order to be able to decide whether
the data on the copied cartridge is useful.
D2D Backup System HP D2D4112 149