Mainframe Training Services SYS-ED Experience

Submit Mainframe Questions


Submit Mainframe Questions

Technology Driven IT Training

Knowledge Base

Submit Mainframe Questions to SYS-ED Advanced search

Interrelated Information Technology

Programming Skills Questions Utilities and Development Tools Questions

The SYS-ED knowledge base is a service for answering questions, inclusive of the research and validation of the accuracy of information in the public domain. Citation of source documentation and examples are used to provide answers to the questions. Utilization of the information of this service and reliance on the answers, information, or other materials received through this website is done at your own risk.


What criteria are used for establishing the amounts for the primary and secondary quantity for a dataset that is to be extracted.


Each track contains approximately 50000 characters. The assumption is that the printout to be extracted has 132 characters on a line. Each track can handle approximately 378 lines (50000/132). It will be necessary to estimate the number of lines in the printout. In EJES, that information is displayed on the right side of the screen on each JOB line. The calculation is rounded up. It is not possible to allocate a half a track or half a cylinder.


What architecture mode is supported for guests operating on IBM's z/VM, running in 64-bit mode?

A z/VM V5 exploits and supports the z/Architecture, which enables 64-bit capable operating systems (Linux on System z, z/OS, z/OS.e, z/VSE V4, and z/TPF) to be run as guests of z/VM V5 when z/VM V5 is running on a System z platform in 64-bit mode. z/VM V5 also supports guest operating systems running in ESA/390 mode such as z/VSE V3, VSE/ESA, TPF, z/OS, Linux on z/OS, or VM/ESA when z/VM V5 is operating in 64-bit mode. In order for z/OS or z/OS.e to operate as a guest of z/VM on the System z platform, both z/VM V5 and z/OS and z/OS.e must be operating in 64-bit mode.

Q What improvements does IBM's z/VM 5.3 bring to the System z platform?
A Enhancements have been made to scalability, security, and virtualization technology. This provides for increased workloads on IBM System z servers and improves its security capabilities. z/VM V5.3 supports LPARs: larger logical partitions; this improves scalability required for growth.

A single z/VM partition can contain:

  • LPARs with up to 256 GB: gigabyte of real storage memory.
  • Up to 32 PUs: Processor Units.
  • More than 1 TB: terabyte of total virtual memory in use by guests.


The PUs can be:

  • CP: Central Processor
  • zAAP: System z Application Assist Processor
  • System z9 Integrated Information Processor
  • System z10 Integrated Information Processor

Q What is SNA and the SNA Protocols?
A SNA stands for System Network Architecture and is a proprietary standard developed by IBM in the 1970's. SNA is a blueprint for a communications network and over the past quarter century IBM has managed its evolution. SNA is not an entity or a product. It specifies the software and hardware products that are available and where they are installed in the network and how the diverse groups of IBM products connect and communicate with each other. SNA does correspond to a certain extent and interoperate with the layers of OSI and TCP/IP; which by contrast are open non-proprietary standards developed in the 1970's.

The SNA protocols defined by IBM are:

3270 Interactive protocol with limited file transfer capabilities. Used primarily for communications between PCs or notebook computers and IBM-compatible mainframes or midrange systems.
3770 Batch file transfer protocol used for Remote Job Entry communications between PCs or notebook computers and IBM-compatible mainframes or midrange systems.
5250 Interactive protocol used primarily for communications between PCs or notebook computers and IBM-compatible midrange systems: IBM AS/400, System/36, System/38, and compatible hosts.

Knowledge of SNA is helpful for implementing web enabling technologies in the IBM mainframe environments.

Q I am a webmaster and Internet programmer who is now being given responsibility for implementing web enablement with IBM systems software - CICS, DB2, and IMS. Can SYS-ED help me?

IBM mainframe systems still have a significant role in the enterprise as data repositories and depending upon your operational objectives, we provide a variety of learning paths for fundamentals and programming skills:

There also are learning paths for IBM system software: 

In 2018, there will be researched and derived learning paths for IBM strategic initiatives - open source cloud, Bluemix, and mobile devices.

Q I am new to the IBM mainframe environment and I have never heard of FICON. What is it and can it also be applied to client/server and web connectivity?
A FICON is a proprietary protocol developed by IBM for use between IBM compatible mainframes and storage. It takes the higher layer ESCON protocol and maps it onto a Fibre Channel transport.

Q I took your CICS Command Level Programming course back in the 1980's. Is the current version of the course much different?
A Portions of the basic coding are relatively unchanged; however a partial list of new facilities/changes includes: compiler enhancements, CICS TCP/IP support, Java and CICS, and Enterprise Java Beans.

This URL can be used to review the new facilities and new workshop exercises:

Q Is WebSphere supported on the IBM mainframe?
A Yes, IBM has a WebSphere Application Server for z/OS. WebSphere Application Server provides the core J2EE architectural support for the deployment of applications. WebSphere MQ, WebSphere Application Server and WebSphere Application Developer are strategic products for IBM and will be used on mainframe systems and across the entire range of IBM operating systems - AIX, Linux, etc.