There are various SAP Blog posts and SAP Help manuals, which describe theoretical processes of the Data Migration in SAP S/4HANA Cloud and how the Migration Cockpit should work. But there are much more useful tips and tricks, which I explored during real Migration project experience, which I would like to describe in this Blog post.
Project lessons learned
- It is certainly very time consuming to migrate firstly all the productive data to Q system, and this could be right, that al productive data are not necessary in the Q system. On the other hand, migrating all the data to Q system firstly, will help with following:
- You will do and check all the necessary customizing and errors´ root cause investigation in Q, so the P productive start will be much smoother.
- All migration templates will be validated during the migration in Q and, in case of the same overall customizing in Q and P, there would be no errors in the migration process in P, what will decrease the P data migration duration significantly.
- If you do all customizing and migration activities initially in Q, this will help greatly with project time-line planning and increase timely go-live probability
- It is an often case, when the migrating data are related to different countries/regions/organizational units etc. The migration process will be significantly improved from performance, organizational and troubleshooting perspectives, if you split it based on the mentioned above structures. It means, that if you migrate data for five countries, you can create separate migration projects for every country from the very beginning and add all the necessary migration objects in each of them. Via this simple operation you gain following advantages:
- Migration project can be simply split in the iterations via this approach: one project = one iteration
- If not all migration templates are ready at a time, you can start with the available and then simply get an overview, which still have to be migrated
- In case of errors during simulation or migration, it would be easier to correct the records, as it would not be necessary to deal with the whole massive of the data
- Performance of excel and SAP S/4HANA Cloud system will be better as well, when the data are split to chunks.
- If you did use the hint from point 2, it is strongly recommended to record all the the errors you had during migration for one unit: most probably you will face the same errors during migration for the next units and, once you documented them it would be easier to apply solutions, you found earlier.
Technical lessons learned
- If you separate items to different migration templates, which refer to one migration object (for example, you would like like migrate separately products and only production materials – they refer to the same migration object) – it is better to create different migration objects in the Migration Cockpit for them. Because if you migrate firstly one file successfully and have errors in the second, it will not be possible to delete all instances, which were transferred to staging tables. You need to mark only those, which were not migrated yet. And this can be quite time consuming.
- To display errors/successful messages in relation to instances – go to migration object and click on the numbers:
- To see the aggregated statistics – use Monitoring functionality:
Changing the grouping from default view to Group By Message ID could be very helpful to get an overview, whether the majority of instances failed during the simulation because of one error or there were various problems:
But before focusing on errors, take a look at the warnings – the root cause quite often is mentioned there.
- Once simulation is done, you can check in system, how data will look like in system´ tables:
- Click on number of instances:
- Select necessary instance, click on it, and on the right hand-side there would be representation of data in system:
- Click on number of instances:
- You can review validation way (App, where to display migrated data) for every migration object on a corresponding SAP Help page: select necessary migration object, scroll down the page and check Post-Processing part
- If all migration templates are ready and checked, and the plan is to run simulation or migration for all objects for example, during time shift – do not forget to increase number of available for the Migration cockpit jobs:
- It is quite easy to forget one obvious point during the migration activities – it is still possible to create records manually in system. And if there is situation, when 1998 records were migrated successfully and for 2 records there is an error message, which does not help to understand root cause (yes, unfortunately, this could be a case), it is worth to try to create records manually – in many situations it works.
Based on the first part of the Blog posts it is worth to say, that data migration is full-fledged stream in terms of SAP S/4HANA Cloud implementation project, which only could look easy in the beginning based on Migration Cockpit simplicity, but finally requires thorough planning, implementation and significant time investments. And the listed technical hints would help the most in case of initial preparation was done right.