We are currently migrating our environment (5 app server, 7 DB server and more than 5000 projects - 2500 active) to ALM 15.51.
As in the past upgrading of such an environment is currently extremely time consuming.
Caused by the huge amount of projects we have to duplicate our environment for every major upgrade and do a partly migration over several months.
Therefore we can´t follow all major versions of ALM ... but we would like to do it (to use new features,....)
If the upgrade process for such amount of projects could be done MUCH faster and we could migrate at least 2000/3000 projects in a few days it would be much easier to stick on the latest major version.
I am sure a faster migration would help all customers in the upgrade initiatives.
There are different strategies to performing an upgrade, some are faster than others.
Migrations are the safest option, and I find these are the most common when the client has put off upgrading for long time.
They end up needing to upgrade not only ALM but the underlying OS and DB at the same time. The tradeoff of course
is that you have to go through the update process you're accustomed to.
Another approach is a side-by-side, but this has higher risk when there are multiple admins involved. And since it looks
like you have clustered environment (or several environments) there would need to be careful planning.
Technical approaches aside, there are also project management approaches that are faster than others.
If you care to discuss in greater detail for your next upgrade, and approaches I've done for large deployments, please DM me.
I believe at this moment, the fastest way to perform bulk DB backup/restore, repository copy manually and restore the projects into target environment. Once you have this ready, ALM robot will help you to migrate these projects at bulk(it's still one at a time but you can start like 100 projects and sit relax). this is of course best-case scenario. If you end up with a repair, upgrade failed then it will take more time.