Stephen Linkin Houston Community College 13-Feb-07 © Mike Murach & Associates, HCC, IBM 1 Managing Tape Data Sets Chapter # 7

2 Objectives Applied objective Code the JCL necessary to allocate a tape data set using: a.one or two units b.one or more specific or non-specific volumes c.whatever form of label processing is appropriate

3 Objectives Knowledge objectives List the reasons tape data sets are used in mainframe shops. Distinguish between tape cartridges and tape reels. Describe the standard labels used for tape data sets. List other types of tape label processing. Explain why tape data may need to be converted between EBCDIC and ASCII format. Distinguish between tape multi-volume files and multi-file volumes. Describe the use of the RETPD or EXPDT parameter in a DD statement for a tape data set. Describe the purpose of the LABEL parameter in a DD statement for a tape data set.

4 A Typical File Backup Process

5 The Labels On A Single File Tape Volume The Labels For A File That Requires Four Volumes The Labels For A Volume That Contains Two Files Standard Label Layouts

6 Syntax Of A DD Statement For A Tape Data Set //ddname DD DSNAME=data-set-name, DISP=(status,normal-disp,abnormal-disp) [,UNIT=(subparameters) ] [,VOL=(subparameters) ] [,RETPD=nnnn | EXPDT=date ] [,LABEL=(subparameters) ] [,DCB=(options) ] Simple DD statements for tape The allocation of an existing cataloged data set //JOURNAL DD DSNAME=MMA2.AR.JOURNAL,DISP=OLD The allocation of an existing uncataloged data set //JOURNAL DD DSNAME=MMA2.AR.JOURNAL,DISP=OLD, UNIT=TAPE,VOL=SER= The allocation of an existing, uncataloged multi-volume data set //JOURNAL DD DSNAME=MMA2.AR.JOURNAL,DISP=OLD, UNIT=TAPE, VOL=SER=(300123,300124,300125,300126) The allocation of a new data set on an unspecified tape volume //JOURNAL DD DSNAME=MMA2.AR.JOURNAL,DISP=(NEW,CATLG,DELETE), UNIT=TAPE

© Mike Murach & Associates, HCC, IBM7 Parameter Syntax (UNIT=) {UNIT=(unit[,count][,DEFER]) {UNIT=AFF=ddname} Examples of UNIT parameters A request for two tape drives UNIT=(TAPE,2) A request that defers the mounting of the tape UNIT=(TAPE,,DEFER) A request for the same tape drive used by TAPEDD1 UNIT=AFF=TAPEDD1

© Mike Murach & Associates, HCC, IBM8 Parameter Syntax (VOL=) VOL=([PRIVATE][,RETAIN][,volume-sequence][,volume-count] [,SER=(serial,serial,...)]) Examples of VOLUME parameters Request for four named volumes VOL=SER=(163013,163014,163015,163016) Non-specific request for up to 20 volumes VOL=(,,,20) Request the third volume of a multi-volume data set VOL=(,,3) Specific request for two private volumes VOL=(PRIVATE,SER=(MMA301,MMA302)) Specific request for a private volume that shouldn’t be dismounted VOL=(PRIVATE,RETAIN,SER=MMA400)

© Mike Murach & Associates, HCC, IBM9 Parameter Syntax (RETPD=) RETPD=nnnn Example of a RETPD parameter //LNMAST DD DSNAME=MMA2.LN.MASTER,DISP=(NEW,KEEP), // UNIT=TAPE,VOL=SER=300123,RETPD=30

© Mike Murach & Associates, HCC, IBM10 Parameter Syntax (EXPDT=) EXPDT= {yyyy/ddd} Example of an EXPDT parameter //JOURNAL DD DSNAME=MMA2.AR.JOURNAL, // DISP=(NEW,CATLG,DELETE) // UNIT=TAPE,EXPDT=2007/180

© Mike Murach & Associates, HCC, IBM11 Parameter Syntax (LABEL=) CodeMeaning SLStandard IBM labels (the default). SULStandard IBM labels as well as user labels. ALISO/ANSI/FIPS version 3 labels. AULISO/ANSI/FIPS version 3 labels and user labels. CodeMeaning NSLNon-standard labels. NLNo labels. BLPMay or may not have labels, but label processing is bypassed. LTMSame as BLP, except that the leading tapemark on the volume is skipped. LABEL=([data-set-sequence][,label-type]) Example of a LABEL parameter //JOURNAL DD DSNAME=MMA2.AR.JOURNAL,DISP=OLD // UNIT=TAPE,VOL=SER=300127,LABEL=3.

© Mike Murach & Associates, HCC, IBM12 Examples Of LABEL Parameters IBM Standard Labels With User Labels LABEL=(,SUL) Processing Of The Fourth Data Set And ISO/ANSI/FIPS Standard Labels LABEL=(4,AL) Label Processing Is Bypassed And The Second Data Set (The First Set Of Data Records On A Tape With Standard Labels) Be Processed LABEL=(2,BLP) The Tape Volume Is Unlabelled LABEL=(,NL)

© Mike Murach & Associates, HCC, IBM13 Parameter Syntax (DCB=) DCB=([DSORG=PS][,RECFM=x][,LRECL=n][,BLKSIZE=n] [,OPTCD=Q] [,DEN=n] [,TRTCH={COMP}{NOCOMP}] Examples of DCB parameters Data set to be written in ASCII format DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=4000,OPTCD=Q) Data set written with 1600 bpi on a dual-density tape drive DCB=(DSORG=PS,RECFM=FB,LRECL=80,BLKSIZE=4000,DEN=3) Data set to be written with compaction on a cartridge tape drive DCB=(DSORG=PS,RECFM=FB,LRECL=80, BLKSIZE=4000,TRTCH=COMP)

© Mike Murach & Associates, HCC, IBM14 End Presentation