Introduction

Introduction

What is SDSF?

SDSF (System Display and Search Facility) is an IBM mainframe tool that allows users to monitor, manage, and control jobs, resources, and outputs in a z/OS environment. It is part of the ISPF (Interactive System Productivity Facility) environment and provides real-time access to information about system operations.

SDSF acts as a central hub for managing jobs (JCL execution), viewing logs, managing output, and controlling other resources.

How It Works:

  • SDSF interfaces with the JES (Job Entry Subsystem), the system component responsible for receiving and executing jobs.
  • Users access SDSF through a terminal emulator by navigating to the SDSF option in ISPF panels.

What is SPOOL?

The SPOOL (Simultaneous Peripheral Operations OnLine) is a intermediate temporary storage area where job-related data, such as input, output, and messages, before those are sent to printer. It is part of the JES (Job Entry Subsystem) and helps manage the flow of jobs efficiently.

When we want to submit a JCL, we use the command 'SUB' or 'SUBMIT' command. After submitting the JCL, we receive a message indicating the jobID, such as:

IKJ56250I JOB MATEDF6(JOB06105) SUBMITTED

We need to make a note os the JobID enclosed in () and is used to check the job status in SPOOL.

After another messages will be thrown to show the job execution status like below -

08.46.52 JOB06105 $HASP165 MATEDF6  ENDED AT MATE  MAXCC=0000 CN(INTERNAL)

The job status can be decided by using the MAXCC (Maximum Condition Code) value which is set by a maximum return code of steps in the JCL.

Return codes -

Return codes indicate the status of a job or step after execution. Here are some common ones:

  • 0 (Zero) - Successful execution without errors.
  • 4 - Warning or minor issues encountered.
  • 8 - Significant errors occurred, requiring attention.
  • 12 - Severe errors that prevent successful execution.
  • 16 - Critical failure; the job could not continue.

Return Code (RC) Vs Maximum Condition Code (MAXCC) -

A return code indicates the status of each step within a job, while the Maximum Condition Code (MAXCC) reflects the highest return code counted by the operating system after the execution of the entire job. The MAXCC is determined by identifying the maximum return code from all the individual steps.

Key Features and Functionalities of SDSF -

  • Job Management: Submit, cancel, or restart jobs. Example: Use the 'SJ' command to submit a JCL file for execution.
  • Viewing Logs and Outputs: Access detailed logs like JESMSGLG, JESYSMSG, and SYSOUT. Example: Select a job in the SDSF panel and type '?' to view output logs.
  • Resource Monitoring: Analyze resource usage and performance metrics. Example: Use 'WHO' to view logged-in users and system load.
  • Spool Management: Manage the JES Spool where job outputs are stored. Example: Use the 'H' (Held output) command to release or delete outputs.
  • Filtering and Sorting: Filter and sort jobs based on criteria like job name, owner, or class. Example: Type 'OWNER userid' to display jobs owned by a specific user.
  • Customizable Displays: Adjust fields, colors, and layouts to match user preferences. Example: Customize columns with the 'SET' command in the SDSF menu.
  • System Commands: Issue system commands directly from SDSF. Example: Type '/D A,L' to display active system components.