IBM OS/390 Test Systems in the Life of the Migration, Production Maintenance Backup Sand-box

Application Development & Test System

A system that is expected to stay up without disruption at least during ²normal working hours². Understand that any outages to this system will affect your applications conversion and testing activities. This logical image may eventually become your production OS/390 system when you cut-over.

Maintenance System The next version of operating system software, or next round of maintenance that will be rolled forward into production. (It is very important to use SMP/E to maintain your OS/390 system.)

This can double as your ªSystems Programmer Sandboxº for testing new operating functions or options that can be brought up and down as desired without worrying about disrupting other users.

This can also be your system on which operators can be trained without fear of reprisal should they do something wrong. This system can be re-IPLed during scheduled times to train operators on startup and shutdown procedures.

After your production cut-over to OS/390, you will also need a ªFall-Back Systemº for backup should the primary production system have too many problems to keep it up. This is different from a ªBackup systemº mentioned above, and may just be a copy of the SYSRES volumes and program libraries at the previous level of maintenance.

26.2 Test Systems in the Life of the Migration

You will need at least three S/390 images during this migration. Here is a simple example of how they can be used at different stages of the migration:

1Initial OS/390 System Installation, Tailoring, and Verification

During this phase, the test system is undergoing frequent changes and may have to be restarted often.

￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿
￿	VSE	￿	￿	OS/390	￿	￿	VSE	￿
￿	Production	￿	￿ Maintenance		￿	￿	Backup	￿
￿		￿	￿	(Sand-box)	￿	￿		￿
￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

2Application Program, JCL, and Data Conversion

During this phase, the test system must be readily available for the programmers and others to make and test changes to the applications. You will also need a systems programming system for applying maintenance, and testing new or modified systems.

￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿
￿	VSE	￿	￿	OS/390	￿	￿OS/390 Maint. ￿
￿	Production	￿	￿ Application		￿	￿----- or -----￿
￿		￿	￿Conver′ n, Test￿			￿ VSE Backup ￿
￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿			￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

420VSE to OS/390 Migration Workbook