StorageTek Host Software Component 6 User Manual

Page of 718
54   VM/HSC 6.0 System Programmer’s Guide
1st ed., 6/30/04 - 312579601
 
Using CDS Rename/Relocate/Expand
The HSC can rename, relocate, and expand an existing CDS(s) without requiring tape 
activity to be suspended or the HSC to be taken down on all hosts.  To use these features, 
users must be at HSC 5.0 or later, however, compatible down-level releases of the HSC 
may be initialized after the CDS has been modified as long as the CDSDEF control 
statements are consistent with the active CDS definitions.
For a rename or relocation operation, the CDS must be disabled (inactive) on all HSC 
hosts to ensure that no active HSC hosts attempt to update or read the target CDS copy 
during a rename or relocation activity.  When using the CDS EXpand function, all CDS 
copies are reformatted at the same time, so all CDSs must be enabled (active) on all hosts.
CDs Command
The CDs operator command provides rename, relocation, and expand capabilities.  Refer 
to the “Commands, Control Statements, and Utilities” chapter in the HSC Operator’s 
Guide
 for a description of the keywords used to perform these operations.
Renaming/Relocating a CDS - Scenarios
To rename and relocate a CDS copy, only one copy of the CDS must be disabled at a time. 
For example,
Renaming a CDS Copy
Before you enable the renamed CDS copy, assume only one CDS has been disabled using 
the CDs Disable command (see above), and ACS.DBASEOLD is renamed to 
ACS.DBASECPY. The inactive (disabled) data set is then enabled using the following 
command:
If the Enable command fails for the renamed CDS, CDS definitions are restored to what 
they were before the command was issued. Users must modify CDSDEF control 
statements to keep them consistent with the active CDS.  
Renaming and Relocating a CDS Copy
To relocate a CDS copy with the CDS Enable command, the user must first create a data 
set containing the appropriate CDS attributes: a fixed, 4096-byte record, single extent, 
physical sequential file. Optionally, users may rename the CDS.
The data set can be created using JCL as shown for the SLICREAT job discussed in the 
HSC Configuration Guide or using the TSO 3.2 Data Set Utility facility.
CDS DISABLE DSN(ACS.DBASEOLD)
CDS ENABLE DSN(ACS.DBASECPY)