Source Code migration from Rocket Aldon to RTC
One answer
I think you have the following options
1. Import a specific baseline and start there. You can import and share a baseline in RTC, then delete the file content, and share a newer baseline and do this repeatedly to import multiple baselines with the loss of some relationships (e.g. renamed files). Keep the old system for some time until it is no longer needed
2. RTC allows to import Subversion with history. If you can export into subversion format, you can use the subversion import
3. Create API based automation that shares the data. https://rsjazz.wordpress.com/2013/10/15/extracting-an-archive-into-jazz-scm-using-the-plain-java-client-libraries/ explains a process that is similar to as explained in 1 and shares baelines, but it could be more fine grained.
Note: I am not a great fan of importing all the history. As always there are tradeoffs.