What is a Virtual Tape Library (VTL)?

A Virtual Tape Library (VTL) is a disk (DASD) based backup system that emulates a real tape library system. For the operating system and to those who use the VTL, it’s like working with real tapes, but in reality it’s disk. A Virtual Tape Library has several benefits: Better backup/restore […]


Common MVS System Address Spaces

The following table lists some of the most common MVS system address spaces: Adress Space Description ANTAS000 Concurrent Copy Support ANTMAIN Concurrent Copy support BPXOINIT USS Address Space initiators CATALOG Catalog Address Space – Handles DISP=SHR, DISP=OLD, and DISP=(…,CATLG) CONSOLE Console Task – operator’s interface DLF Data Look aside Facility […]

Command keyboard key

Useful DFSMShsm User Commands

The following table describes the DFSMShsm user commands that can be used for storage administration: Command Description HALTERDS HAL Changes the data set parameters that affect backup. This command only applies to NON-SMS managed datasets. Syntax: HALTERDS (dsname/password…)       FREQUENCY(days) or SYSFREQUENCY       VERSIONS(limit) or SYSVERSIONS Examples: HALTERDS PARTSTST.CNTL VERSIONS(13) FREQUENCY(999) HALTERDS […]


Delete content of a sequential dataset using IDCAMS

The following JCL will delete the content of a sequential dataset without deleting it using the IDCAMS utility: //DELCONT  EXEC PGM=IDCAMS //DDDMMY   DD DUMMY //DDOUT    DD DISP=SHR,DSN=USER1.MYDATA.EXAMPLE //SYSPRINT DD SYSOUT=* //SYSOUT   DD SYSOUT=* //SYSIN    DD * REPRO IFILE(DDDMMY) OFILE(DDOUT)   Replace USER1.MYDATA.EXAMPLE by the sequential dataset you wish to delete […]