Picking the right migration strategy
When migrating to a new platform, you have different options:
- High-fidelity migration: You try to migrate as much as possible to the new platform.
- Clean cut-over migration: You only migrate the bare minimum that is necessary to start working on the new platform.
High-fidelity migrations to complex platforms have different problems. The main problem is that there is not a 1-to-1 mapping of all entities and that things just work differently on different platforms. By migrating everything over, you influence the way people use the new system. The data is optimized for the old system using old processes. Also, the time, costs, and complexity involved in a high-fidelity migration are not linear. The more you try to get to 100% fidelity, the more complex and expensive it gets, and 100% is normally not achievable at all (see Figure 21.1).