VSAM Essentials Workshop

This hands-on course describes and explains the access method concepts in MVS and the structure and design of VSAM files. It teaches how to create VSAM files using the utility Access Method Services (AMS), both from a functional as well as a performance point of view.
Additionally, it provides the Systems Programmer and Operational Analyst with information on the structure of ICF catalogs and the related VTOC and Index VTOC.
Online exercises provide experience in creating, accessing and managing VSAM files. Attendees will create and use clusters, alternate indexes and paths.

This course is also available for one-company, on-site presentations and for live presentation over the Internet, via the Virtual Classroom Environment service.

Classroom dates (High Wycombe) - click to book!

25 April 2018 4 June 2018

Virtual Classroom Environment dates - click to book!

26 March 2018 20 August 2018

What is a 'Virtual Classroom Environment'?


What do I need?

  • webcam
  • headphones with microphone
  • sufficient bandwidth, at least 1.5 Mb/s in each direction.


On successful completion of this course you will be able to:

  • describe and explain the concepts of the z/OS access methods
  • analyse the structure of the RRDS, ESDS, KSDS and LDS data sets
  • use the Access Method Services utility program IDCAMS to define, load, backup, monitor and manipulate VSAM data sets with particular emphasis on the KSDS file type
  • develop guidelines for optimised allocation of VSAM files for use at their installation
  • identify performance related issues in the batch and online environments that can be found when using the KSDS file type.

Who Should Attend

All programmers, systems programmers, operators and operations analysts.


Familiarity with basic z/OS principles and a working knowledge of TSO/ISPF and JCL.


3 days

Fee (per attendee)

£1475 (ex VAT)

Course Code



VSAM Overview

MVS and I/O processing; MVS access methods; VSAM terminology; VSAM data set structures: ESDS, RRDS, KSDS, linear data sets; ICF catalogs and VTOCs.

VSAM Data Set Structure

Control Areas; Control Intervals; CI structure spanned records; CI splits; CA splits.

Using Access Method Services

Modal commands; creating VSAM clusters; Modal command examples; error messages.

Defining VSAM Data Sets

Define command; define cluster parameters; space allocations; defining ESDS, KSDS & RRDS.

Listing Catalog Information

Listcat command; listcat options.

VSAM Data Set Management

Management commands; REPRO; REPRO options; copying & merging.

Alternate Indexes

Defining an AIX; BLDINDEX; UPGRADE vs UPDATE; using AIX.

VSAM Data Integrity

VSAM SHAREOPTIONS; Cross System Sharing; passwords; EXPORT/IMPORT.

VSAM Performance Considerations

Bufferspace; KSDS space requirements; NSR; LSR.

© RSM Technology 2018