Experienced SAP users are in agreement in pointing to a Proof of Concept Upgrade project as one of the best expenditures of time and money you can make to ensure the success of an SAP Upgrade. Why exactly is this?
Such a project consists of copying your productive environment to a new system (or systems), performing the technical Upgrade on that system, and then performing initial functional testing. Software testing tools may be involved as well.
As no two SAP systems—comprised of servers, software, configuration, data and connecting elements—are exactly the same, it pays to have this heads-up preview of just how much effort will be involved in your Upgrade. It is commonly advised to run a Proof of Concept Upgrade six months before the planned start of an Upgrade project, for in doing so several important things are accomplished:
The closer your Proof of Concept Upgrade is to your existing productive landscape, the better. The cost of exactly reproducing all systems involved is offset by the help it gives in identifying compatibility issues. The landscape to be used should, in any case, be isolated from the operative one. But plan on using a full database copy of production data for the system to ensure that data-related issues are replicated during the sandbox phase.