Operations Support
Part Three - Challenge #02


Mainframe systems are designed to be used by large numbers of people. The vast majority of these people are unaware they are using a mainframe. For example: When you check your bank balance using your smartphone, it is not the smartphone that has your bank balance, it is a mainframe. When you make an airline reservation, it is not the browser or smartphone the completed the transaction, it is a mainframe. Many more examples exist.

The sophistication and complexity of these z Systems that serve the users require a variety of roles for 7x24x365 support. Additionally, separation of duties are implemented to insure adequate control and audit requirements. These systems should never depend upon one person.

The system operator monitors and controls the z Systems mainframe hardware and software. The operator monitors the system consoles for abnormnal conditions, and works with the system programming and production control staff to ensure the health and normal operation of the systems.

Actually, the majority of the z Systems mainframe data center operational tasks are automated. However, as an airplane has autopilot, it is best to have an experienced pilot in the plane in case something goes wrong to execute unplanned course corrections, etc.

This challenge includes use of SDSF to process z/OS commands.

While SDSF has commands, / at the SDSF command prompt will display of System Command Extension panel or / followed by a system command will execute the system command. All system commands and responses are written to the system log (SYSLOG)

SDSF has a user log for collecting command input and responses for the immediate session. Take the following actions to understand how it works:

  • =sd ; ulog
  • /d t
  • /d a,l
  • /d tcpip,,netstat,home
  • /d ts,l
  • ulog
  • ulog close
  • ulog
  • /d omvs,options
  • ulog
  • print odsn p3.output(#02)
  • print
  • print close
  • ulog close

The above resulted in P3.OUTPUT(#02) written with the content of ULOG which includes the system commands followed by the system command responses.

Take a moment to view the following link. Quickly scroll through the entire IBM Knowledge Center link page to observe all that is available related to z/OS MVS System Commands.

z/OS MVS System Commands Reference

Your Challenge

The system program linklist, aka LNKLST, is a list of libraries containing executable modules. When JCL is submitted to execute a program, this system program link list is searched by default to locate the JCL requested program.

z/OS MVS System Command Reference IBM Knowledge Center link is available to display information about the LNKLST set.

Locate and execute the z/OS MVS System Command to display the system program linklist. Enter this system command using SDSF ULOG, then print the system command and response to P3.OUTPUT(#02)

Next: Challenge #03