October 10, 2018
Unfortuntely Dropbox has seen fit to drop support for CentOS 7, and is dropping support for xfs filesystems, which is what we use (and the default on CentOS 7).
The possibility of reformatting /scratch as ext4 was discussed, but unfortunately the new requirements also indicate that glibc 2.19 or higher is required. This would seem to disqualify CentOS 7 since it is distributed with glibc 2.17. So simply changing /scratch to ext4 would not be enough.
As a workaround, one could try rclone. Unlike the Dropbox app, rclone isn't a daemon that looks for file changes so it can sync them automatically. One would have to run rclone as a cronjob. If you decide to go this route, please run the cronjob on your desktop machine.
Another solution might be to switch to Google drive and use rclone with that.