Cloning at instance upgrade

[miyu]

We would like to upgrade three instances of our development, test, and production instance.
Which instance should I clone?
Is it possible to upgrade each instance without creating a clone?

[Tony Chatfield1 · Accepted solution]

Hi, there are no enforced constraints and it is possible to upgrade any instance without a clone,
but not cloning Prod to sub-production so that you can test an upgrade against current configuration and data is not best practice and increases the chances of your Prod upgrade encountering unexpected issues.

I would normally clone Prod instance to Dev
Upgrade Dev and resolve any issues\dependencies
Then clone Prod to Test, apply any update-sets that result from the Dev, upgrade and test\validate the upgrade process (including updates sets) repeating the entire process if necessary.

Once happy with the upgrade process, import Test update sets to Prod (but don't apply)
Then clone Prod to Dev and Test before your upgrade so that you have an update-to-date instance as a reference (Test) and an up-to-date instance (Dev) should any development work to be required to resolve unexpected issues with your Production upgrade.

Then apply your Test update sets and upgrade Prod.
Finally once Prod is upgraded and everyone is happy clone Dev and Test 1 last time so any future development is made against the 'current' production baseline.