1

Using the Subsystem Display (3.1), prepare a work paper that shows the name, origin, and number of functions supported by each subsystem.

Determine that adequate documentation is available that describes the purpose, use, and function of each user‑defined subsystem.

2

One of the ways that subsystems can be defined to z/OS is in the logical Parmlib.

Use the Parmlib IPL Map display (2.1.1) to locate the active IEFSSNxx member of the logical Parmlib. Select and browse this member to obtain a list of subsystems. Compare this list to the Subsystem Display (3.1) and note any differences observed.

3

Subsystems are usually started at z/OS IPL in one of the following ways:

• Automatically, by Parmlib
• Automatically, by an initialization program named in IEFSSNxx
• Manually, by the operator

Obtain a copy of the operator’s log sheet (SYSLOG) and note the operator‑started subsystems. Determine that adequate documentation is available for the operator’s use.

4

Test the use of the logical Parmlib to permit automatic start‑up of subsystems.

Use the Parmlib IPL Map display (2.1.1) to locate the active COMMNDxx member and match its contents to the operator’s SYSLOG.

5

z/OS use SMF to pass parameters to subsystems. Use the SMF Options Display (1.5.1) to determine the active SMFPRMxx Parmlib member.

Use the Parmlib IPL Map display (2.1.1) to select and browse that member. Determine if any parameters are passed to the subsystems noted in Step 1 through the SUBPARM SMF parameter.

6

Use the Parmlib Member Status display (2.1.2) to determine if the SMFPRMxx or IEFSSNxx members of the logical Parmlib changed since the last review.

7

If changes were found in Step 4, use the File History Search display (6.5) to search SMF for updates to SYS1.PARMLIB.

If an archival copy of logical Parmlib data sets is available, use the File Comparison display (6.4) to determine exactly what was changed. Check the ISPF/PDF statistics for each logical Parmlib data set for additional information.

8

Determine that any changes found in Step 4 and documented in Step 5 are supported by proper change control authorization procedures and approval records.

9

Because z/OS require that JCL for nondynamic subsystems be stored in the procedure library (SYS1.PROCLIB) or one of its concatenations, use the JES2 Proclib Display (4.2) to locate and browse the JCL for each subsystem. See the Usage Guide for information about dynamic subsystems, such as IMS and SOF.

10

Look for JOBLIB or STEPLIB statements in the subsystem JCL to determine if the subsystem program is loaded from a private or system LINKLST library. Use the File History Search display (6.5) or your access control software to determine if these libraries are protected from unauthorized access and modification.