FIXCDS: Displaying, creating, or modifying a record in the MCDS, BCDS, or OCDS

The FIXCDS command displays or modifies records in the migration control data set (MCDS), backup control data set (BCDS), or offline control data set (OCDS). You can display a record in one of the control data sets with FIXCDS and then by issuing FIXCDS again, make changes to that record. A record consists of a key field (44 bytes), followed by a header field (20 bytes), followed by variable data.

Use the FIXCDS command to fix minor problems that occur in the control data sets. For example, you can use the FIXCDS command when the audit process finds a discrepancy between the computing system catalog and the MCDS.

Use the DISPLAY parameter of the FIXCDS command to display the data before you change it. Then, after you change a control data set record, verify that the change was successful by again specifying the DISPLAY parameter of the FIXCDS command.

Although DFSMShsm keeps copies of the following records in working storage, the changes you specify with the FIXCDS command for these types of records are made only to the DASD copy of the following records:

Backup control record (BCR)
Daily statistics record (DSR)
Migration level-2 control record (L2CR)
Management control record (MCR)
JES3 volume activity count record (VAC)
Volume statistics record (VSR)

If you want the virtual storage copy of the above records to keep the changes you make to the records, use the PATCH command. Otherwise, the changes you made to the CDS records with the FIXCDS command are replaced with the unchanged records from the virtual storage copy.

Use the FIXCDS command to make the following changes to the MCDS, BCDS, and OCDS:

Delete a control data set record (DELETE).
Expand a control data set record by a specified number of bytes (EXPAND).
Rename a control data set record by specifying a new key (NEWKEY).
Change existing data at the specified offset in a control data set record (PATCH).
Create a new record in one of the control data sets (CREATE).

Use the FIXCDS command to make the following changes only to the MCDS:

Add a new MCDS data set record for a migrated data set residing on the volume that you specify (ADDMIGRATEDDATASET).
Turn the assigned bit on or off in the MCDS for a migrated data set record to show the migration status of a data set (ASSIGNEDBIT).

Use the FIXCDS command to request the refresh of all of the BVRs in the BCDS (REFRESH) during the next DFSMShsm CDS backup.

You can request a printout of the SYSOUT data set.

Note: For information on DFSMShsm supported patches, refer to z/OS DFSMShsm Implementation and Customization Guide .