Mei 31, 2014. Marked the last day of an IT implementation in one of our client, starting tomorrow a new SAP system will be used. As usual, project team comprises of consultants and client’s team members gathered from noon to ensure a smooth process of data transfer, ie ending balance. Since this was a retail client, most critical data transfer started after their retail stores closed which was at 10PM. This has been a routine activity for me as consultant, staying up late the night before the new systems Go Live, we often camped overnight at project site for the next 2-3 days waiting for the data to be ready.
Sometimes I wonder why we have to undergo these painful experiences over and over again. I personally feel these activities have become more challenging for me as I age after having experienced it for almost 25 years. Is there any way we can skip this? Well actually it depends on the Cutover Strategy that you decide. The term “Cutover” means the transfer of final data from the old to the new systems.
In general, there are 2 (two) Cutover Strategies:
1. Parallel Run
Parallel Run is running both the old and new systems at the same time over an agreed period, say 3 months. Once users are comfortable with the new systems, eg no errors, reports generated from both systems are the same, the old system will be dropped hence only new systems runs.
The advantages of this strategy are to minimize the risk and to have back up plan should the new system fails.
The weakness of this strategy is that user’s workload will be heavier as they have to enter the data 2 times, both into the new and old systems. Additionally, users may need more time to reconcile any output differences generated by the two systems. There is tendency of assuming that old system is always the correct one. Based on my experience, user will subconsciously prioritize entering the transaction into the old systems, hence new system may be neglected and as a result the project seems to drag on. The longer the parallel run is, the heavier the workload for the users. It is very inconvenient having to perform data input 2 times longer.
2. Cut Off
This strategy is clearer as once the new systems Go Live then the old system is no longer used. Sometimes we call this strategy “Cold Cutover”. Main advantage of this strategy is that users need to focus only on one system, no double entry and less reconciliation.
However, this strategy also comes with risks. But there are methods to mitigate the risks. Another point to note is the Cutover Night described above whereby final data transfer takes place. This strategy requires commitment and discipline of all stakeholders from top management to all users, external parties such as consultants, hardware vendors, building management etc.
So what strategy is the best? To tell the truth, both have advantages and weaknesses. Every client has its unique situation and condition. Complexity of operation, data quality and user readiness are among the factors that need to be considered. All risks have to be identified and mitigation plan as well as contingency plan needs to be developed to ensure a smooth cutover.