I currently use Borg for all my backups. To have a remote backup I placed my old Synology NAS at a family member and connected it to tailscale (via a tailscale docker container). That way I could also can do Borg backups to that remote NAS.
Though I have problems with the stability of the tailscale connection from the NAS. And honestly, I’m a bit tired to fix these problems.
I would like to have a self hosted backup solution, that can reach the synology NAS. I would like to avoid port forwarding at my family members network (for obvious reasons). I have a VPS in the internet that I can use for a common self hosted contact point (like I setup headscale there instead of using official Tailscale servers).
What would be your way for handling these remote backups?
You don’t have to be on the NAS’ physical network to run some tests, if you can SSH into it, that’s enough to run some speed tests and latency tests to reference servers (e.g. Google, netflix, …), while doing the same from your PC simultaneously. Whenever you encounter “instabilities” you should be able to see which side of the connection is struggling more than usual. You should also be able to monitor the NAS itself for excessive IO or CPU using something like htop (even though that would be rather extraordinary if all that’s going on with it at that time is a Borg backup).
On the topic of Kopia, you can go the easy route of setting up a SFTP remote pointing to your NAS. All you need is SSH access to the NAS (so your current tailscale/borg set-up qualifies as is) and a folder where the SSH user can write. You can then compare backup times vs. Borg (in my use case, going from 18-25min with Borg down to 3-5min with Kopia). If you then want to try the HTTP repository server, there is a container for that, but the set-up is a bit annoying (the password to decrypt the repo needs to be stored on the NAS, you need to generate a SSL certificate pair and have the client whitelist the sha256sum of it, etc). Personally I haven’t found a substantial advantage to having the http repository server but YMMV.