Defining extrapartition data sets

You can define each extrapartition data set for either input only or output only, but not for both.

About this task

Define transient data extrapartition data sets used as queues for CICS® messages with a record length of 132 bytes and a record format of V or VB. If you use the FREE=CLOSE parameter for an input extrapartition entry, be aware that it is usable only once in the CICS session. Any attempt to read the queue after it has been CLOSEd and OPENed again results in the IOERR condition being raised.

If you decide to specify VBS for the extrapartition data set, be aware that BFTEK=A should be specified on the definition in the JCL. When variable-length spanned records are processed without the extended logical record interface (XLRI), and a record area is provided for a logical record interface (LRI) (BFTEK=A has been specified in the data control clock), QSAM will provide an area large enough to contain the maximum record size (up to 32756 bytes). Failure to specify BFTEK=A on such data set definitions can result in run time errors such as abend 002 returned from the access method.

If you want to encrypt the data sets, see Encrypting data sets.

Sample JCL to define transient data extrapartition data sets

In Figure 1, the high level qualifier (CICSTSnn.CICS) assumes the release level of CICS TS beta. You must adapt it for your own CICS release.

Figure 1. Sample JCL to define transient data extrapartition data sets

//LOGUSR  DD   DSN=CICSTS64.CICS.applid.LOGUSR,DISP=(NEW,KEEP),
//        DCB=(DSORG=PS,RECFM=V,BLKSIZE=136),
//        VOL=SER=volid,UNIT=3380,SPACE=(CYL,2)
//MSGUSR  DD   SYSOUT=A