We previously upgraded from R12.0 to R12.52 several years ago via the "parallel upgrade" method. Now it's time to upgrade again, but this time from R12.52 SP1 to R12.8. The previous upgrade was our first SM Policy server upgrade and it took us a lot of time in the sandbox environment encountering many mistakes until we perfected the process. We basically installed a fresh R12.52 PS server and then exported the r12.0 policystore data and then imported it to the new r12.52 policystore via "smobjexport" and "smobjimport" commands.
I think the trickiest part of this was exporting and importing the policystore data and also the agent keys between the old and new PS. We plan to do the exact same process with this round of upgrade from 12.52 to 12.8 and hoping folks would chime in to give us any advice or tips.
Much thanks in advance!