I am once again looking for some best practices advice from the Spiceworks Army. We have some SQL Server-based applications that we routinely need to move between filesystems. The problem we face is that these systems are in use and being changed until the moment we take them down for the move. A typical move usually involves 5-9 TB of files and data.
The problem we perpetually face is that upper management wants near-zero downtime for the customers when these moves occur. We have previously tried to stand-up a mirror of the source system in the new location, but this remains a costly and difficult proposition to pull off. The most difficult part is in trying to keep the mirror databases synced. I am open to any/all ideas, best practices, tools, etc. that others have used to solve this type of problem.