I guess that is where my confusion is coming in to play. I have one license with the software update subscription, so I can upgrade to 10, but I'd like to do so on new hardware with a new OS install. My concern is that I do the upgrade to 10, effectively changing my license to 10 and removing my license for 8, and then something doesn't work and I want to roll back, but can't because of licensing.
So I guess I'm looking at two scenarios, and need to know which is least likely to toast my environment. My end goal in either scenario is to be on a new OS install, as the current OS install appears to have some issues. Also, I'd like to keep IP's so clients don't need to update DNS, etc, but I might just need to migrate to the new server with new IP's, decommission the old server, then change IP's on the new server to match what they were to begin with.
1. Upgrade current server to 10. I'd like to do this by cloning to another system to test the upgrade, and once I am comfortable that all has worked, look at doing a "live" upgrade. Finally, migrate to a new OS install. How is my license affected in this scenario? Do I need to upgrade my license to 10 in order to perform the upgrade? What happens if the upgrade messes up for any reason (the underlying OS on the live server is suspect, which is why I'd ultimately like to move to a new install).
2. Migrate from my live 8 server to a test 10 server. When I am confident that all is working, go ahead and perform a final migration. This seems to be the best scenario because there are fewer steps but it is unclear how the licensing is affected in this scenario. Would I need to get a temporary license from sales for the destination server, and when the migration is complete, upgrade my license to 10 and activate it on the new server? Then I could go through the whole IP change process.
Overall, it seems that process 2 is cleaner and easier, if it is possible...