Managing customizations when consolidating systems
In a consolidation scenario, you might need to migrate application customizations into the target system to support functionality that users expect in the source systems. To successfully consolidate system, review all the customizations you intend to bring forward to ensure that the implementation:
- Will not adversely impact any existing users of the target system.
- Will not conflict or duplicate customizations that are already or will be implemented in the consolidated system.
- Will work correctly for the new version of the application if the consolidation is combined with an upgrade.
All customizations should be technically validated, explicitly tested, and signed off as part of user acceptance testing. You should implement these customizations in the target production system prior to the cutover of the system. Doing so reduces the complexity of the cutover and reduces risk by giving the customizations time to "bed in" prior to the major change of the consolidation cutover.
The following diagram illustrates the decisions that you should make when managing customizations as part of a consolidation scenario.
In short, this process requires that you create a copy of your current production database, upgrade the underlying AR System and use the Best Practice Conversion Utility (BPCU) to identify and convert your customizations to overlays.
After the BMC process is complete, we recommend that you export the customizations and import them into your clean installation of ITSM.
Where the same AR System object has been overlaid on the source and the target systems, you cannot migrate the overlay without overwriting the existing overlay. An AR System developer must review and manually merge the overlays.
The output from this process is a package of AR System definition files that will be imported into:
- Data migration target prior to data migration
- Target production system prior to cutover
You cannot finalize the BMC Helix Data Manager Data migration package until all data model customizations are complete, so creating this package is a key milestone for the consolidation project. Additionally, this package is also the trigger for all workflow customizations to be put under change freeze in the source and target production systems that are involved in consolidation. For more details, see Change-management-when-consolidating-systems.