I'm happy to ask this question privately, as it is more of a sales question, but in case it's welcome here:

Is it possible to use MirrorSync to Sync a single, local, FileMaker file on a laptop, with a backup of the same file on an external hard drive, without using a server? I'm trying to avoid using server because my file, for sake of argument, contains 100GB of remote container data, and I do not want the costs associated with massive online storage, or the physical limitations, and hardware responsibility, of running my own server and only having access to my data when I'm at my office. I would use Carbon Copy Cloner or Time Machine, but advice elsewhere suggests that these programs can corrupt an open database.

No, MirrorSync is not designed for this purpose.

Ok, thanks for the fast reply. Do you have any suggestions for how to back up a 100GB FileMaker document manager solution that lives locally on a laptop?

You'll need to periodically close the database manually, then make a copy, then re-open it.

Thank you.