I haven’t used it, but it seems designed for that use case (FTA: “If you do not want to back up FILESTREAM data with relational data, you can use a partial backup to exclude FILESTREAM filegroups.”)
There are some caveats we'll have to consider though.
> Encryption is not supported on FILESTREAM data.
We currently are under contract to always have data encrypted at rest for some customers. (Yay enterprise!)
> SQL logins will not work with FILESTREAM containers. Only NTFS or ReFS authentication will work with FILESTREAM containers.
We've got so many different environments that our database is hosted in, so this could be hard to do, but perhaps possible. A lot of governmental facilities as customers that will not connect their data to the internet means a real headache when introducing changes.
But I'll still will spend some time to evaluate this. It seems like the easiest technology to introduce and migrate to.
I think that means you can’t have MSSQL encrypt FILESTREAM columns, but still can have them stored in a file system that encrypts data (if so, that still may be different in the sense that the file system uses a single encryption key, while the database may support multiple ones, but data will be encrypted at rest)