As I mentioned in another thread I got it working with Duplicati, but to get of every cloud backup solution, and use the QNAP remotely for backup, I need to have my Proxmox Backup Server able to do S3 backup as well.
I can get the config accepted in Proxmox, but as soon as I try to create a Datastore for the backup, and I have to select a bucket, it fails with an error 400.
So I’m unsure what is wrong, as the message really doesn’t explain itself, and I don’t see anything on the QNAP about which error it made and more importantly, why?
The 400 error in Proxmox is not caused by the S3 API itself, but by SSL certificate validation.
If QuObjects is using a self-signed certificate, Proxmox requires you to manually provide the certificate’s SHA-256 fingerprint when creating the S3 endpoint. Otherwise, the request will be rejected and return a 400 error.
You can obtain the fingerprint using the following command (replace the IP/Port accordingly): openssl s_client -connect : </dev/null 2>/dev/null
| openssl x509 -fingerprint -sha256 -noout -in /dev/stdin
Also, please make sure to enable Path Style access mode, otherwise it may cause connection issues as well.