Selfhosted

So, I've been pushing my photos to local immich-instance and I'll need some kind of file storage too soon, total amount of data is roughly 1,5TB.

Everything is running on a proxmox server and that's running somewhat smoothly, but now I'd need to get that backed up offsite. I'm running a VPS at Hetzner and they offer pretty decently priced S3 storage or 'storagebox' which is just a raw disk you can connect via SMB/NFS and others.

Now, the question is, how to set up automated backups from proxmox to either of those solutions? I suppose I could just mount anything to the host locally and set up backup paths accordingly, but should the mount drop for whatever reason is proxmox smart enough to notice that actual storage is missing and not fill small local drive with backups?

Encryption would be nice too, but that might be a bit too much to ask. I have enough bandwidth to manage everything and after initial upload the data doesn't change that much, the only question is what is the best practise to do it?