StorageTek Host Software Component 6.0, Руководство системного программиста

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106 VM/HSC 6.0 System Programmer’s Guide
1st ed., 6/30/04 - 312579601
Defining Unit Attributes (UNITATTR)
UNITATTR statements describe the recording technique attributes of library and
nonlibrary transports. Transports are described by:
• unit address
• transport model number.
To allow the HSC to operate correctly, the user must specify UNITATTR statements
for all
nonlibrary transport models that appear to the operating system as 3490E-type
and 3590-type devices. For library devices, the model type is determined by the LMU.
Refer to “Unit Attribute (UNITATTR) Control Statement” on page 136 for more
information.
Collections of transports with common characteristics can be identified with a single
UNITATTR statement by specifying a list of unit addresses, range of addresses, or
multiple ranges of addresses.
The UNITDEF command causes the HSC to open the definition data set containing the
UNITATTR statements. See “Unit Attribute Definition (UNITDEF) Command and
Control Statement” on page 140 and “Unit Attribute (UNITATTR) Control Statement” on
page 136 for descriptions of syntax and parameters.
Defining Volume Attributes (VOLATTR)
VOLATTR statements describe the media type and recording technique attributes of
cartridge tape volumes.
Volumes are described by:
• volume serial number (VOLSER)
• media type
• recording technique.
To allow the HSC to operate correctly, the user must define VOLATTR statements
for all ECART, ZCART, helical, 9840/T9840B (STK1), and T9940A media. Volumes
not defined by VOLATTRs are presumed to be standard capacity cartridges
.
Note: Alternatives to defining VOLATTR statements are available. Refer to “Volume
Attribute (VOLATTR) Control Statement” on page 143 for more information.
Collections of cartridges with common attributes can be identified in a single VOLATTR
statement by specifying ranges and lists of VOLSERs, or using wild card characters.
Scratch counts are based entirely on VOLATTR information. Accurately defined
VOLATTR control statements are critical for correct processing of nonspecific
volume requests.
For specific mounts, the actual media type, as determined by the LMU, overrides
what is specified in the VOLATTR.