Hi,
simple question: is it possible to backup FROM a WebDAV-Storage to some other e.g. local disc?
Hello @bzdega and welcome to the forum!
If you mean can Duplicati directly use Storage Type of WebDAV as Source Data, then I don’t think it can, however if there is a way to access the underlying storage in some way that looks like files, there might be.
Alternatively, perhaps you could use a helper like WebDAV in rclone to clone to local storage for a backup.
Duplicati has support for many protocols (including WebDAV and rclone) for destination but not for source.
If you map a drive letter to your WebDAV storage, you can add source files and folders from that drive letter in Duplicati.
I’ve tried it by mapping a drive letter to my OneDrive for Business storage and was able to backup some files and folders. It’s quite slow, but it works.
Thanks! I started wondering if this was using third-party software, but it looks like Windows comes with it, e.g.
and (assuming time stamps work) seems good enough to make it look like files, thus keeping Duplicati happy. Running as Tray Icon rather than Windows service might be necessary, in order to get to this new drive letter.
Just because it hasn’t been mentioned here I’d like to provide some performance advice.
If you can back up locally on the device hosting the WebDAV, do so. It will perform much better 
There is nothing wrong with mounting in remote resources and backing them up, but Duplicati isn’t designed for it so the decision should be made with open eyes about performance penalties.
Was there any development regarding the option of different sources?
If it would just be the same options for sources than for targets this would be useful for so many replication jobs from one cloud storage to another whatever server.
Or does anyone know a solution which offers that?
Initializing a backup from the source isn’t very secure as if the source gets hacked usually quite easily the backup systems can be reached as well, as credentials for the backup target must be somewhere on the source machine.
It’s more complex than that and it sounds like it’s unlikely to happen. There is an open feature request for it, and here’s a comment from the main developer: non-local backup sources (such as SFTP) would be great! (and, why not allow all destinations as source as well? :) · Issue #2726 · duplicati/duplicati · GitHub
rclone is my go-to tool for local-to-cloud, cloud-to-local, or cloud-to-cloud sync. But note it is a sync tool not a backup tool.
Definitely true - job configs include passwords for back end storage are in the Duplicati-server.sqlite file. This file is encrypted by default on Windows, albeit with a default password. You can use a different password if you wish, but the password still must be on the system somewhere.
Not sure how likely it is that someone would hack your system with knowledge of Duplicati specifically with an intent to get at your back end credentials. It’s a risk you’d have to evaluate based on your needs and desires.