Mount share on remote system as a disk?

[Xaero]

Okay so here's the deal; I have a few not super tech savvy people that need a reliable way to upload several terabytes worth of disk images to my server for off-site backup of assets. I've tried using WireGuard, but sometimes I add a user or remove a user and all of the users before or after the user will become unusable and I have to do a lot of manual prodding to keep things in order. I want things to be less involved for me, while still being easy to use for them.
So I set up Owncloud - and added my shares as external storage. "This is awesome!" I thought; until I realized that with WebDAV we are limited to ~4gb no matter what, and with the client we have to sync the entire directory and have no option to mount the share as a local disk. The WebUI works but isn't really suitable for the workflow.
Okay, so I did a bit of Googling and found out that Owncloud basically became Nextcloud and Nexcloud has an experimental disk mount option! FANTASTIC!

Wrong again. The disk mount is based on DokanFS and crashes when attempting to open external share folders. DokanFS has been a thorn in my side before. It's not pleasant to work with, and ends up resulting in me manually prodding things even more than wireguard was.

 

Back to square one. Seafile. Looks like it has a robust client application with the ability to mount to a drive letter on Windows machines! So I set it up... ony to realize that it uses its own block based storage system and requires all data be added into Seafile itself.

Is there any way to do what I'm trying to do without a ton of manual upkeep?

In the past I used SSHFS and CIFS over SSH tunnels, and it worked perfectly. But I had to maintain keys and passwords manually. I also had to set up each and every client (I mean, I used a script to do it - but it still required ME to do the setup) and there was plenty of manual intervention. I'd like something where users can be added and removed quickly and easily, forgotten passwords can be handled by the individuals, and the application is point and click driven for setup.


End goals:

- WebUI
- Access data on Unraid shares
- User management.

- Mount as a local filesystem (drive on windows, path on Linux) without syncing all contents.

PS: For reference, I'm in a different state than the machines the images are being captured from. I need them to be backed up offsite, for my own peace of mind. There are two backups currently (one a hot spare disk, the other the image that spare was created from) but nothing off site. Prior to me becoming involved, there was no backup. Once its backed up to my unraid server I will back up the important images to the cloud. (Some of them can be rebuilt, it's tedious but otherwise disposable data; others are proprietary encrypted filesystems and must be byte-perfect)

Edited December 7, 2019 by Xaero