The CICS Db2 test environment

When setting up your CICS® Db2® test environment, consider how many CICS systems you want to connect to your Db2 systems.

You can connect more than one CICS system to the same Db2 system. However, the CICS Db2 attachment facility does not allow you to connect one CICS system to more than one Db2 system at a time.

You can set up production and test environments with:
  • A single CICS system connected to one Db2 system
  • Two or more CICS systems for production and test, connected to the same Db2 system
  • Two or more CICS systems connected to two or more different Db2 systems

The first alternative, using a single CICS system for both production and test, is not recommended because applications in test could affect the performance of the production system.

The second alternative, with just one Db2 system, could be used for both test and production. Whether it is suitable depends on the development and production environments involved. Running a test CICS system and a production CICS system separately allows test failures without impacting production.

The third alternative, with, for example, one test and one production Db2 system, is the most flexible. Two CICS subsystems can run with one or more Db2 systems. Where the CICS systems are attached to different Db2 systems:
  • User data and the Db2 catalog are not shared. This is an advantage if you want to separate test data from production data.
  • Wrong design or program errors in tested applications do not affect the performance in the production system.
  • Authorization within the test system can be less strict because production data is not available. When two CICS systems are connected to the same Db2 system, authorization must be strictly controlled, both in terms of the functions and the data that are available to programmers.