Vts Management Policies Window (By Pools) - IBM TotalStorage 3494 Tape Library Operator's Manual

Management Policies (VTS x) window (shown in Figure 149).
Figure 149. VTS Management Policies Window (by Pools)
The Free Storage Threshold , measured in gigabytes (GB), defines the capacity of all
the empty stacked volumes in the VTS or TS7700 Virtualization Engine and
provides a warning when the VTS or TS7700 Virtualization Engine is running low
on free storage, A threshold is provided for each VTS or TS7700 Virtualization
Engine installed in the library and is entered in GB. The default value is 600 GB.
The VTS Active Data window (Figure 99 on page 173) displays the Free Storage
Threshold as the Free Storage Alarm Level. If the free storage drops below the
threshold (alarm level), the Library Manager signals an intervention-required
condition to notify you to add more stacked volumes.
The Free Storage Threshold value specified in the VTS/VE Management Policies
window. The number of stacked volumes required to store the Free Storage
Threshold depends on the compression of data (when writing from the tape
volume cache to the stacked volume) and the type and model of tape drive
associated with the VTS or TS7700 Virtualization Engine (3592 J1A Tape Drive,
3590 B1A, E1A, or H1A tape drives).
v The 3494 B18, B10, and B20 VTSs with enhanced ESCON host attachments
provide compression into the tape volume cache. Therefore, further compression
when writing to the stacked volume is unlikely, and the capacity of a J media
stacked volume is approximately 10 GB for 3590 B1A Tape Drives, 20 GB for
3590 E1A Tape Drives, 30 GB for 3590 H1A Tape Drives.
v The capacity for a K media stacked volume is approximately 20 GB for 3590 B1A
Tape Drives, 40 GB for 3590 E1A Tape Drives, and 60 GB for 3590 H1A Tape
Drives.
v The capacity for a JA media stacked volume is approximately 300 GB for a 3592
J1A Tape Drive or a 3592 E05 Tape Drive emulating a 3592 J1A Tape Drive.
v The capacity for a JB media stacked volume is approximately 700 GB for a 3592
J1A Tape Drive or a 3592 E05 Tape Drive emulating a 3592 J1A Tape Drive.
v The capacity for a JJ media stacked volume is approximately 60 GB for a 3592
J1A Tape Drive or a 3592 E05 Tape Drive emulating a 3592 J1A Tape Drive.
Chapter 6. Advanced Operating Procedures
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