Disadvantages Of Export; Compression; Cartridge Import - HP StorageWorks D2D100 - Backup System User Manual

Disadvantages of Export

1. Restores may take longer if a physical cartridge is required for the restore.
2. Backup applications may require the exported cartridge for the next job in their rotation scheme.

Compression

When you are moving data from the HP D2D to physical tape, it is important to be aware that the
cartridge maximum size is the native size (without compression). HP StorageWorks tape drives apply
hardware compression, therefore, the data from the HP D2D Backup System is likely to require less space
on a physical tape cartridge. When moving data to a physical cartridge for off-site storage, there is no
need for concern if the data seems to utilize less space.
The capacity quoted for physical media assumes that the tape drive will be able to compress your data
and reduce the file sizes by 50%, but this can be achieved only if your data is not already compressed.
For example, JPEG pictures, movies, music or ZIP files, are already in compressed formats: spreadsheets,
text files, high-resolution graphics are not. Most users have a mixture of compressed and uncompressed
data and seldom achieve 50% compression.
Some users may choose to enable software compression from their backup application to increase
the storage space available to the backup application, but this can make backup jobs slower to run.
However, once software compression has been applied, the data is not further compressed when it is
exported to a physical tape directly attached to the HP D2D Backup System. This ensures that the user
knows exactly how much physical cartridge space is required for export or copy.

Cartridge import

The Web interface on the HP D2D is used to Import cartridge data from the attached tape drive to the
mail slot on the HP D2D Backup System. The backup application on the host is used to move the data
from the mail slot back into one of the library slots.
Physical
Tape Drive
Cartridge
Figure 39 Cartridge import
When you import a cartridge:
• If it is less than 200 GB, the cartridge Max Size is set to 200 GB.
• If it is over 200 GB, the cartridge Max Size is set to 400 GB.
• If it is over 400 GB, the cartridge Max Size is set to 800 GB.
98
Export, import and copy using an attached tape drive
Step 1
Use HP D2D Web Management
Interface to import from tape
drive.
1
Mailslot 2
3
4
5
6
7
8
Library
HP StorageWorks D2D Backup System
Step 2
Use backup application on host
to move the mail slot cartridge
back to autoloader slot.
1
Mailslot 2
3
4
5
6
7
8
Library
HP StorageWorks D2D Backup System