StorageTek Host Software Component 6.0, Руководство системного программиста

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50 VM/HSC 6.0 System Programmer’s Guide
1st ed., 6/30/04 - 312579601
primary copy. If a standby CDS copy is active, the new primary CDS copy is copied
over the standby CDS copy, and the standby becomes the new secondary copy.
• If a standby CDS copy is active, and a failure occurs in accessing the secondary CDS
copy, the current primary CDS copy is copied over the standby CDS copy, and the
standby becomes the new secondary copy.
To utilize full automatic CDS recovery capabilities of the HSC, StorageTek recommends
that all three CDS copies (primary, secondary, and standby) should be used. CDS copies
must be created (by the SLICREAT program), defined to the HSC (by the CDSDEF
control statement in PARMLIB), and active (by the CDs Enable/Disable command). CDS
copies should be located on different DASD volumes for redundancy.
For more details about automatic CDS recovery, refer to “Control Data Set Recovery” on
page 49 and “CDS Recovery Capabilities” on page 439 .
Automatic Recognition of Configuration Changes
Some changes to the library configuration are automatically recognized by the HSC.
Automatic Update of LSM from 4410 to 9310
When an LSM comes online, the LSM type is reported to the HSC by the LMU. If the
LSM is defined in the CDS as a 4410, but it is actually a 9310 (PowderHorn), the LSM
type is automatically updated in the CDS. Thus, an LSM upgrade from a 4410 to a 9310 is
automatically recognized and recorded in the CDS without running the Reconfiguration
utility.
Note: Replacing a 9310 with a 4410 LSM does not result in an automatic update of
the LSM type. (In some cases the hardware report of this change may not be
accurate.)
If an LSM is defined to the HSC as a 9310, but it is actually a 4410, the HSC
manages it without problems, since the panel configurations and LMU requests and
responses are the same for 4410 and 9310 LSMs. However, HSC preferencing by
LSM type will not work correctly using MNTD SCRDISM(CURRENT/ARCHIVE)
for scratch dismount requests.
Run-time Recognition of 9740 CAP Configuration
The 9740 CAP can either be a 14-cell array, or it can hold a 10-cell removable magazine.
The HSC recognizes the current CAP size when the LSM is modified online. This allows
the user to change the 9740 CAP configuration without running the Reconfiguration utility
or recycling the HSC.
Using the SET Utility Instead of LIBGEN and Reconfiguration
Changing a configuration using the Reconfiguration utility requires a global outage. Many
of the changes made by the SET utility can be performed while HSC subsystems are up