Allocate a data set using SMS class specifications: Example 1

In this example, the ALLOCATE command is used to allocate a new data set. By providing the SMS data class, management class, and storage class, you can take advantage of the attributes assigned by your storage administrator through the ACS routines.

Although this example includes DYNAMNBR, it is not required in this example. Because this example contains two DD statements, you can do up to two allocations. DYNAMNBR is required only when the number of allocations exceeds the number of DD statements. This example sets DYNAMNBR to 1. This allows up to three allocations for each DD statement (2) plus DYNAMNBR (1).

//ALLOC    JOB  ...
           EC PGM=IDCAMS,DYNAMNBR=1
//SYSPRINT DD   SYSOUT=A
//SYSIN    DD   *
     ALLOC -
           DSNAME(ALX.ALLOCATE.EXAMP1) -
           NEW CATALOG -
           DATACLAS(STANDARD) -
           STORCLAS(FAST) -
           MGMTCLAS(VSAM)
/*

Because the system syntax checks and ignores SMS classes when SMS is inactive, and because no overriding attributes are given, this example works only if SMS is active. The parameters are:

DSNAME states that the name of the data set being allocated is ALX.ALLOCATE.EXAMP1.
NEW creates a data set.
CATALOG retains the data set by the system in the catalog after step termination. This is mandatory for SMS-managed data sets.
DATACLAS gives an installation-defined name of a data class to be assigned to this new data set. The data set assumes the RECORG or RECFM, LRECL, KEYLEN, KEYOFF, AVGREC, SPACE, EXPDT or RETPD, VOLUME, CISIZE, FREESPACE, SHAREOPTIONS, and IMBED or REPLICATE parameters assigned to this data class by the ACS routines. This parameter is optional. If it is not used, the data set assumes the default data class assigned by the ACS routines.
STORCLAS gives an installation-defined name of an SMS storage class to be assigned to this new data set. This storage class and the ACS routines are used to determine the volume. This parameter is optional and, if not given, the data set assumes the default storage class assigned by the ACS routines.
MGMTCLAS is the installation-defined name of an SMS management class to be assigned to this new data set. The data set assumes the migration and backup criteria assigned to this management class by the ACS routines. This parameter is optional and, if not given, the data set assumes the default management class assigned by the ACS routines.