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Adding TL895 Libraries to the Compaq Enterprise Backup Storage System
Server Information
Enter a server name and the estimated total Gigabytes of data to be backed up.
Figure 4-4. Server Information screen
Determining the Configured Primary Storage System
The primary storage configuration is an important link in the backup performance calculation. It
has a direct effect on the speed at which the server can send data to the tape device. Select the
type and configuration that most closely matches your server’s primary storage system. Pull
down the menu selections for various hard disk controllers to select the approximate feed speed
of the primary storage system. You may also select Automatic to test the performance of disk
drives physically connected to the machine the sizer tool is running on.
Ideal primary storage feed speed would be above three times the backup rate (3:1) of each DLT
drive. This will allow the data to stream to the DLT drive and achieve near 100% performance.
If the feed speed is 2:1 but less than 3:1, the backup performance is reduced by approximately
20%. If the feed speed is less than 2:1, the backup performance is reduced by approximately
50%. The sizer tool uses the reduction ratios to better estimate the actual performance for
various primary storage controller systems.
IMPORTANT:
These percentages are only estimates and individual performance may vary.