I was thinking about renting a Hetzner Storage Box for restic backups.
It seems to support sftp, WebDAV, and rest-server via rclone. Which one would be preferable regarding speed and reliability? Anything else I should know about?
If I were to use sftp, can I use ControlPersist and Compression in the ssh config?
Thanks!
Look at this article:
The idea is to run rclone in append-only mode with an SSH forced command. This means, if someone hijacks your system, they cannot SSH into the storage box and destroy your backup.
Hey, welcome to the forum.
rest-server would probably be my personal choice. You can run it in append-only mode if you need to protect against someone compromising the system performing the backups.
I think there’s probably no point in using Compression in the ssh config; modern restic (since 0.14.0) compresses all the data being sent to the repository anyway, so you would be burning additional cpu cycles for no measurable benefit.
You could use ControlPersist, but I think the measurable benefit is going to be in the order of seconds, which would likely be absolutely dwarfed by the time taken to perform the backup as a whole. Still, it could be worth benchmarking/experimenting with this to see if it helps with your specific setup 
See my thread here:
But yeah, in a nutshell, for certain operations, I find Rclone+WebDAV to be fastest and is what I use. SFTP works fine too though.
Definitely don’t use compression with SFTP though - the data will already be compressed.