I know the AS/400 is very stable -- but costly. If we have one person supporting the AS/400 while we switch to SQL Server, how many people would we need? How many servers do you keep on adding if you add instances? I am concerned with the cost.
In the migration projects in which I was involved, the same system administrators still support the environment as they did before the migration. A transition period was needed, however, during which everyone had to get to know the new environment.
The best thing to do in order to compare the needed resources, would be to contact several hardware vendors. They can easily size a target environment based on an Early Watch Session conducted on the current environment. In addition, the OS/DB Migration Service from SAP verifies the source and suggests modifications to the target environment before the go-live, in order to avoid the unexpected.
This was first published in February 2006