IAM/PLEX JCL procedure

Multiple IAM/PLEX address spaces

You can run one full function IAM/PLEX instance per LPAR of the same RLSGROUP. You can have other IAM/PLEX instances of the same RLSGROUP on the same LPAR. If the REMOTERLS parameter is not specified, then it uses REMOTERLS parameter by default if there is already a ROUTER IAM/PLEX instance for the RLSGROUP on the LPAR. A REMOTERLS region is a FILESERVER-only region and cannot be connected directly by a batch job or CICS region. You can start more IAM/PLEX regions that are part of a different RLSGROUP on the same LPAR. You can also have a mix of IAM/PLEX regions and IAM/RLS regions on the same LPAR.

You might decide to run multiple IAM/PLEX address spaces for the following reasons: 

• To isolate different applications so that a failure in one application grouping does not affect other unrelated applications.
• For billing purposes, to isolate as much processing as possible for different applications or customers by eliminating common server address spaces.
• For security purposes, to isolate some applications from others.

Whatever the reason, to use multiple IAM/PLEX address spaces, you must have well defined groups of data sets and processing that can be isolated from each other.

Using multiple IAM/PLEX address spaces is subject to the following restrictions:

• A batch job, CICS region, or TSO user can only be directly connected to only one IAM/PLEX instance. All IAM data sets that require IAM/PLEX processing for that user address space must be handled by an IAM/PLEX instance that is a member of the same RLSGROUP as the IAM/PLEX that it is connected to.
• An IAM data set can only be opened by only one IAM/PLEX instance at a time.
• Each IAM/PLEX instance must be started with its own unique procedure and name.
• Each IAM/PLEX instance in an RLSGROUP must use the SYSTEM LOGGER, and the LOGSTREAM must be defined as part of a STRUCTURE in the coupling facility.
• All IAM/PLEX instances in the SYSPLEX must use the same data set name table.
• Each IAM/PLEX instance requires its own system LX. A system LX is the facility through which cross-memory access to the IAM/PLEX address space is authorized. Owing to system limitations on the number of system LXs, this restricts the maximum number of IAM/PLEX address spaces that you can use, unless the address space is started with the REUSASID=YES parameter on the START command for the IAM/RLS procedure. To use the REUSASID=YES parameter, make sure that the DIAGxx member in parmlib also specifies REUSASID(YES).

IAM/PLEX procedure

The IAMSAMP that was part of the installation package, contains the following sample IAM/PLEX procedure. You can be edit this sample and copy it into one of your system proclibs. You must change the data set name of the IAM load library and the data set name of the card image PDS to be used for parameters and overrides. You can change the default member names for the IAM/PLEX parameters and for the IAM/PLEX override.

IAM/PLEX TEST procedure

You can use the PARM=’TEST,JOBNAME=(JOBX*) parameter in your IAM/PLEX startup procedure to start a test version of the IAM VSAM interface (VIF). You must set up a different procedure by using a unique RLSID and start the procedure with a STEPLIB to the load library for the level being tested. To run a job using the test IAM/PLEX you use the same STEPLIB and specify the RLSID of the test IAM/PLEX. If you start the (VIF) before starting IAM/PLEX, then you must put the PARM=’TEST,JOBNAME=(JOBX*)’ in the procedure that you use to start VIF. 

The test job names in the following sample are specified by the JOB parameter when the IAMPLEXT procedure runs:

Sample of TEST IAM/PLEX PROC Member IAMPLEXT in IAMSAMP

IAM/PLEX DD statements

The following table describes the DD statements in the IAM/PLEX procedure: