Kenneth Fisher shares some thoughts on SSISDB:
We’ve been doing a lot of upgrading recently and at one point had to move an instance from one 2016 server to another. In the process, we found out (the hard way) that it’s not that easy to move SSISDB (the SSIS Catalog that may or may not be named SSISDB). I mean it’s not hard, but it’s definitely not a basic backup/restore. The full BOL instructions on how to do this are here. That said, here are the elements that are involved.
Read on for the list as well as an order of operations.