Customizing the DSSOPT DD statement

You can use the DSSOPT DD statement to replace the DFSMSdss DUMP, COPY, and RESTORE commands that are used by DFSMSrmm. You might want to customize the operands based on the media that you used for the backup, the copy, or the resource that you have available.

Figure 1 shows examples of the DFSMSdss DUMP, COPY, and RESTORE commands that DFSMSrmm issues. You can replace the second line of the commands that are shown in Figure 1 with one or more DFSMSdss options. If you decide to change the commands, specify all the operands you want to have processed because DFSMSrmm uses your input in place of its own.

Figure 1. DFSMSdss commands that are issued by DFSMSrmm

 DUMP DS(INCLUDE(cds_name)) OUTDD(BACKUP) SHARE -
    COMPRESS CONCURRENT VALIDATE OPTIMIZE(1)

 COPY DS(INCLUDE(cds_name)) [OUTDD(BACKUP)] SHARE –
    FR(PREF) CONCURRENT  RENAMEU((**.CDS,**.COPYCDS)) REPLACEU

 RESTORE DS(INCLUDE(**)) INDD(BACKUP) -
    REPLACE

The command operands that you can specify in the DSSOPT DD statement are controlled and validated by DFSMSdss, not by DFSMSrmm. If you specify an unsupported command operand, DFSMSdss fails the operation.

The COPY command used by DFSMSrmm includes the OUTDD(BACKUP) keyword only if you have specified the BACKUP DD. When the OUTDD keyword is not specified, processing relies on SMS ACS processing being used to determine the target volume. You can override this processing by specifying the OUTDD keyword in DSSOPT or by specifying any other alternative DFSMSdss keyword that directs where the target copy is to be created.

The COPY command includes FR(PREF) combined with the CONCURRENT keyword. This enables the use of FlashCopy, concurrent or virtual concurrent copy if possible. If this is possible, a non-intrusive backup is performed to create a CDS copy. Otherwise, the backup continues, but CDS updates are prevented until the CDS copy completes. An alternative approach you can use with the DSSOPT DD is to cause the copy to fail if one of these methods cannot be used. For example:

FR(PREF) CONCURRENT(VIRTUALREQ) RENAMEU((*.CDS.**,*.COPYCDS.**)) REPLACEU
or
FR(PREF) CONCURRENT(ANYREQ) RENAMEU((*.CDS.**,*.COPYCDS.**)) REPLACEU

Do not specify FR(PREF) without the CONCURRENT keyword or the FR(REQ) keyword, because this causes processing to be intrusive.

The RENAMEU keyword on the COPY command specifies a filter mask (**.CDS) and renaming rule (**.COPYCDS). This changes the ending qualifier of the copied data set from '.CDS' to '.COPYCDS'. If your control data set name does not end in ',CDS' or you want to use a different renaming rule, you must use DSSOPT to override the second line of the command. See z/OS DFSMSdfp Storage Administration for details of the use of RENAMEU.

The REPLACE keyword on the RESTORE command ensures that when you recover the DFSMSrmm control data set from a backup, any existing control data set is reused when possible or reallocated if necessary. If you are increasing the size of the control data set and have preallocated a larger control data set, specify the REPLACE keyword to restore to the preallocated data set.

The DSSOPT DD statement can be specified for dump, copy, and restore operations. DFSMSrmm reads all the records and uses them to replace its default command operands beginning at the second line. You can include comments in the DSSOPT records by using DFSMSdss conventions.

Example: Ensure that DFSMSdss does not compress the data and that the tape hardware is used to compress the records. This example uses EDGHSKP to back up to tape. To use EDGBKUP, the backup data sets must be allocated on DASD.

//EDGBKUP  EXEC PGM=EDGHSKP,PARM='BACKUP(DSS)'
//SYSPRINT DD SYSOUT=*
//MESSAGE  DD SYSOUT=* 
//BACKUP   DD DISP=(,CATLG),UNIT=TAPE,DSN=BACKUP.CDS(+1),
//         LABEL=(,SL)
//JRNLBKUP DD DISP=(,CATLG),UNIT=TAPE,DSN=BACKUP.JRNL(+1),
//         RECFM=VB,LRECL=9248,
//         LABEL=(2,SL),VOL=REF=*.BACKUP
//DSSOPT   DD *
    CONCURRENT OPTIMIZE(4) VALIDATE
/*

Example: Rename the control data set during restore processing. The restored control data set is renamed when DFSMSdss renames each of the components of the backup copy of the original DFSMSrmm control data set. The example also shows how to restore the control data set and forward recover it to a volume different from the volume on which it was backed up. When the control data set is renamed during the restore, do not specify the MASTER DD statement unless it identifies the predefined target data set.

//EDGBKUP  EXEC PGM=EDGBKUP,PARM='RESTORE'
//SYSPRINT DD SYSOUT=*
//BACKUP   DD DISP=SHR,UNIT=TAPE,DSN=BACKUP.CDS(0)
//JOURNAL  DD DISP=SHR,DSN=BACKUP.JOURNAL(0)
//         DD DISP=SHR,DSN=RMM.JOURNAL
//NEWVOL   DD DISP=SHR,VOL=SER=MYVOLX
//DSSOPT   DD *
/*RESTORE TO NEW VOLUME,AND
RENAME THE CDS */
OUTDD(NEWVOL)RENAMEU((*.CDS,*.NEWCDS))

Example: Create a copy of the control data set using fast replication. The copy of the control data set is created using a new data set name based on the current CDS dsname. The example ensures that fast replication is used so that an almost instant copy of the CDS can be created. No journal backup is created in this example. The example is run with DFSMSrmm active so that the MASTER DD is not required. The CDS data set name is obtained from the running DFSMSrmm subsystem. The data set name of the copy is created from the existing CDS data set name. The second qualifier of CDS is renamed to COPYCDS. The copy is almost instant, and this is a non-intrusive copy of the CDS. Updates to the CDS are allowed during backup.

//EDGBKUP EXEC PGM=EDGBKUP,PARM='BACKUP(COPY)'
//SYSPRINT DD SYSOUT=*
//BACKUP DD DISP=SHR,UNIT=SYSDA,VOL=SER=myvol
//DSSOPT DD *
  FR(PREF) CC(ANYREQ) RENAMEU((*.CDS.**,*.COPYCDS.**)) REPLACEU
/*