If you don't trust Dropbox you should encrypt your files before copying them to the Dropbox folder because you can't trust the client too. You should encrypt them with a key the client cannot read from fs. Basically you're going to use it as a backup service because you won't be able to work on files in the DB folder. Maybe one of those file systems that work in user space and store only encrypted data will do. Check this http://www.howtogeek.com/121737/how-to-encrypt-cloud-storage...