Verification Requirements in the Migrated Environment:
It is highly important to have a verification process built in for a migration testing process. By putting out the
The following tests are designed for a hypothetical test case.
- Check whether all the data in the legacy is migrated to the new application within the downtime that was planned. To ensure this, compare the number of records between legacy and the new application for each table and views in the database. Also, report the time taken to move say 10000 records.
- Check whether all the schema changes (fields and tables added or removed) as per the new system are updated.
- Data migrated from the legacy to new application should retain its value and format unless it is not specified to do so. To ensure this, compare data values between legacy and new application’s database.
- Test the migrated data against the new application. Here cover a maximum number of possible cases. To ensure 100% coverage with respect to data migration verification, use the automated testing tool.
- Check for database security.
- Check for data integrity for all possible sample records.
- Check and ensure that the earlier supported functionality in the legacy system works as expected in the new system.
- Check the data flow within the application which covers most of the components.
- The interface between the components should be extensively tested, as the data should not be modified, lost, and corrupted when it is going through components. Integration test cases can be used to verify this.
- Check for legacy data redundancy. No legacy data should be duplicated itself during migration
- Check for data mismatch cases like data type changed, storing format is changed etc.,
- All the field level checks in the legacy application should be covered in the new application as well
- Any data addition in the new application should not reflect back on the legacy
- Updating legacy application’s data through the new application should be supported. Once updated in the new application, it should not reflect back on the legacy.
- Deleting the legacy application’s data in the new application should be supported. Once deleted in the new application, it should not delete data in legacy as well.
- Verify that the changes made to the legacy system support the new functionality delivered as a part of the new system.
- Verify the users from the legacy system can continue to use both the old functionality and new functionality, especially the ones where the changes are involved. Execute the test cases and the test results stored during the Pre-migration testing.
- Create new users on the system and carry out tests to ensure that functionality from the legacy as well as the new application, supports the newly created users and it works fine.
- Carry out functionality related tests with a variety of data samples (different age group, users from different region etc.,)
- It is also required to verify if ‘Feature Flags’ are enabled for the new features and switching it on/off enables the features to turn on and off.
- Performance testing is important to ensure that migration to new system/software has not degraded the performance of the system.
- It is also required to carry out Load and stress tests to ensure the system stability.
- Verify that the software upgrade has not opened up any security vulnerabilities and hence carry out security testing, especially in the area where changes have been made to the system during migration.
- Usability is another aspect which is to be verified, wherein if GUI layout/front-end system has changed or any functionality has changed, what is the Ease of Use that the end user is feeling as compared to the legacy system.
Since the scope of Post-Migration testing becomes large, it is ideal to segregate the important tests that need to be done first to qualify that Migration is successful and then carry out the remaining later.
It is also advisable to automate the end to end functional test cases and other possible test cases so that the testing time can be reduced and the results would be available quickly.