IET Customer Profile

DTO is an agency of the Dutch Ministry of Defence. The company acts like a software house for the Ministry. For robust business applications, CA Gen is used as the development tool.

This paper describes how DTO has used the GuardIEn Production Update Exit to meet special requirements. Why and What are described below.

When we started to customise GuardIEn in 1996 we had a big challenge. The challenge was to meet the same level of support as an existing Configuration Management system for host legacy systems. This system was able to handle all the steps to get an application running in an environment and the steps to make back-ups of source code to an archive dataset. The data-centre of our company expected that GuardIEn could do the same for CA Gen host applications.

We made a list of production update steps that had to be performed by GuardIEn. Most of them were covered by the steps that are provided as standard steps with GuardIEn. We had to use the Production Update Exit (GDPUEXIT) to meet additional site specific requirements. The Exit provides customers with the ability to develop customised steps themselves.

The exit had to generate JCL for several specific steps, for instance:

• File transfer to a production machine using FTP
• BIND of DB2 Plans on the development machine and the production machine
• BIND of DB2 Packages on the development machine and the production machine
• Copy EAB source code to an archive dataset (VSAM) that could keep several versions of the EAB

We started to customise the Production Update Exit COBOL program (GDPUEXIT), but thought it would be nice to create a parameterised program without hard-coded JCL. Not doing this meant we had to change, compile and link the program for every little update.

We have created a file that contains JCL Skeletons for the above steps. This file is input for the GDPUEXIT. For variables such as dataset names or deliverable-ids there is a parameter designed in the JCL that can be substituted by the exit program. The pieces in the JCL that are repeatable for every deliverable are marked with special characters. Using the import views of the exit, the repeatable part is populated for every deliverable of the subject deliverable type. The result is a fully working generated JCL that performs the step we want.

Where the import view of the Exit was not sufficient to give all the needed information, IET added extra attributes to the import views for us. For instance we needed the version number to store source code in the archive file.

We are now able to cover the whole life-cycle without using manual steps. For example, the Update for a Pre-Production environment contains the following steps:

• Migration of the changed deliverables from Test to Pre-Production;
• Copy of EAB source code from Test to Pre-Production;
• External source code is compiled and linked;
• CA Gen is invoked to generate the source code and this is then installed on the development machine (where GuardIEn resides) in a pre-production environment;
• Bind control cards are generated for DB2 Plans and Packages;
• Loadmodules, DBRMs and Bind Control Cards are transferred to a Production Machine;
• On the Production machine the DB2 Binds are performed in the Pre-Production environment.

In the Pre-Production environment the result is tested. When the customers of the application grant permission to turnover to the production environment (this is done by changing the status of the Change Request), the Update for the Production environment is started:

• Bind control cards are generated by GuardIEn on the development machine and transferred to the Production Environment on the Production machine;
• The load modules and DBRMs are copied from the Pre-Production to the Production environment on the Production machine;
• DB2 Binds are performed for Production;
• A copy of the EAB-source code and other external sources (EXTNs and EXLMs) is made to a VSAM cumulative archive dataset.

The GuardIEn system as well as the IET Company proved to be flexible in our case. We now have a robust solution that covers our requirements on the host platform. No time consuming and error prone manual steps are needed anymore. The development of the exit program was not easy considering all of the extra processing that we decided was necessary for our environment, but the result was good.