What is software migration?
Software migration describes the changeover from old software to a new application. An existing software system is partially or completely transferred to a new target environment.
The background to a software migration is that the previous system is to be replaced by the new one, e.g. B. because the legacy system is out of date, because the new environment offers additional or better functionality or because the requirements for the system in general have changed so much that migration is the most efficient solution.
Software migration: standard software or individual solution?
Migrating to more modern technologies is a common way to modernize outdated legacy systems. You have the choice: Do you switch to an off-the-peg solution that is typical for the industry or do you have an individual solution developed that exactly matches your own ideas? Often there is still a kind of middle ground in which the manufacturer offers individual adjustments for its standard software for a fee.
Which method you choose depends on the requirements of the system and the needs of the company. Unchanged standard software is z. B. the cheapest solution, but may not fit optimally with the established business processes. Custom software, on the other hand, costs a lot of time, work and money, but offers exactly the functions that a company needs in everyday life. Another central criterion is the feasibility of the data migration.
Carefully plan your data migration
The migration of existing data is a central point in software migration. Business data is invaluable to businesses and organizations. They contain all the important information that is necessary for day-to-day business, e.g. B. customer data or invoice data. So if you want to switch to a new system, the data has to move with it. In order for this to work smoothly, it must be carefully analyzed and planned in advance.
One of the worst scenarios would be that all data is lost when migrating to a new system. That would be catastrophic for the company, but it is also the absolute extreme case and can be avoided with appropriate data backups. A more likely scenario is that some of the data is lost during the migration or is incorrectly transferred to the new system. Because one problem with data migration from legacy systems to modern applications is that different data models are used in each case.
If you switch from legacy software to custom-made software, you still have a good understanding of how the data migration has to work. You can roughly plan the process during development and design the data model of the new application in such a way that all data is mapped as intended. But if you switch from legacy software to standard software that is typical for the industry, you have to come to terms with the data model that the respective manufacturer has chosen.
On the one hand, there is the problem that the structures can look very different. You have to work with a solution that restructures the existing model in a technically correct and complete manner in the new model before the data is brought into the new system. And then there is another problem: What should happen if some data fields from the legacy system do not appear in the new software? Here, too, you have to choose a solution in which the data is retained as completely as possible.
Planning for the timing of the data migration
Part of the strategic data migration is also the question of when it is possible to work with the new system and thus from what point in time new data records can be created. It may be necessary that all inventory data must first be transferred to the new system before new data can be added.
This is e.g. B. the case when a direct replacement of the old system without a transition phase is desired. In this constellation, work must be paused until all data has been properly transferred and then verified. With large amounts of data, this can mean a break for days. Since this is often impossible, there are strategies that can circumvent the problem, e.g. B:
Temporary parallel operation: The legacy system is used in parallel with the new system until the old data has been migrated and the quality of the migration has been verified. Both systems have to be filled with newly created data for a short period of time. This means additional work, be it through a technical solution or for the user himself. However, it also quickly becomes clear whether the new system reliably delivers the desired results.
Gradual changeover: If possible, the legacy system can be migrated to a new system component by component. Parts of the old and new software are operated in parallel in phases, be it on the surface or in the background via appropriate interfaces. In this way, selected complexes can always be converted to the new system and checked during operation. This procedure requires a lot of planning. In addition, the complete migration takes noticeably longer because only individual parts of the software are converted. However, the small-scale procedure results in a more precise control of the results. This makes the procedure more robust overall against data loss or data corruption. This makes the process clearer, especially for large amounts of data.