Application migration with a new database
Application migration with a new database uses a parallel target production environment that is configured differently from the source production environment. You configure a new database when creating the target environment and selectively redeploy applications from the source environment to the target environment.
When to use application migration with a new database
When you use application migration with a new database, you are free to create a target environment that is configured from scratch differently from the production environment. The redeployed applications create their own database tables and application data in the parallel production environment. They do not have access to the application data stored in the databases configured for the source production environment.
Application migration with a new database is supported for migration from the following products:
- IBM BPM Advanced V7.5 or V7.5.1
- IBM BPM Standard V7.5 or V7.5.1
- WebSphere Process Server V7.0.0.x or V6.2.x
- WebSphere Lombardi Edition V7.x
- WebSphere Lombardi Edition V6.x
Use the application migration method with a new database in the following scenarios:
- You want to move your applications to the new version without a dependency on the authoring tools and the development environment.
- You want to reconfigure your topology as part of the process of migrating to the new version of IBM BPM.
- You do not have long-running process instances and human tasks, or you can run parallel production environments while you drain the process instances and human tasks in the source environment as new instances are started in the target production environment.
- You have application data in queues or failed events in product databases that were created in the source environment that can be managed to completion in the source production environment while new messages and events are routed in parallel to the target production environment.
- You cannot incur any downtime in your production environment and can concurrently manage parallel source and target production environments.
- You want to redeploy applications selectively from your source production environment to your target production environment.
Benefits
Application migration with a new database provides the following benefits:
- No dependency on the development tools
- Target production environment can be configured differently from the source production environment since configuration is not automatically migrated from the source to the target
- Parallel production environment supported:
- Selective application migration
- No downtime
- Ability to perform extensive testing before migrating to production environment, but usually regression testing is enough
- No dependency on migration tools
Costs
Application migration with a new database incurs the following costs:
- Existing data is not moved; new database tables are created
- New features are not enabled automatically and sometimes unavailable without migrating the application artifacts using artifact migration
- Manual (scripted) deployment of applications is required
- Requires updates to client applications
- Hardware and software licenses might need to be evaluated for any additional licenses required when running in parallel
Risks
Application migration with a new database involves the following risks:
- Existing user applications should continue to run in the new runtime at the same level of function they had in the old runtime. In some cases, however, there might be a change in code on which the application depends, such as a JDK change, which might have a negative impact on the unchanged application.
High-level tasks
Application migration with a new database includes the following high-level tasks:
- Install the new product version.
- Configure your parallel production environment.
- Manually deploy applications using the previous version EAR files or .twx files from the source environment. You can perform the application deployment using the administrative console or the Process Center console on the target environment.
- Optional: Run both environments in parallel so that business process instances and human task instances that are in progress finish in the source environment and new instances start in the target environment.