found it!!
You should provide the path as follows:
/home/duplicati_path
Not using /volume1 or /var or…
Discovered that by connecting via ftp, and the url did not have the /volume/ or /var path in it.
Could you please confirm this works for you as well?
Wim
Great! Though I can’t confirm it (no Synology box, saddly) but perhaps @David_Jameson hasn’t uninstalled Duplicati yet and can give it a try…
Bloody hell — that worked! You know, when I was experimenting with WebDav and opened a Finder folder to the Synology, I noticed there was a single “home” folder there as well as the “homes/user” folder. I actually went looking for that ‘home’ folder but couldn’t find it anywhere.
So ok, did that, and I have started a backup of one hard drive. Keeping my fingers crossed — and THANKS so much for figuring it out.
Of course from a technical point of view, I’m curious as to WHY this worked and why the previous mechanisms did NOT work?
you are welcome & good luck!!
my 2 cents: synology exposes the home folder differently than a normal Linux-based OS…
Probably google outside duplicati can help us further here… As I don’t think this is duplicati related…
Wow! I had no idea you needed to do that. Awesome that you figured it out.
Now that I know this, I think you could have found out by using FileZilla or CyberDuck to connect, as it would show the paths.
I do recall that Synology monkey patches sshd with some login integration. It sounds like they patched sftp as well such that it does not expose the /volume stuff, which is really confusing as they have not (and could not) patch normal ssh access the same way.
it was with an ftp client (firefox 
) that I noticed the path difference…
So is your hard drive backed up now?
If so, please consider clicking the checkmark in Wim_Jansen’s post so other users know that’s the trick that slaved the issue. 
God no, it still has 361,000 files (522GB) to backup — I’m assuming it’s going to be 3 or 4 more days given that we started with 750,000 files or so. But you’re right - the suggestion worked so I’ll mark that.
I don’t have CyberDuck any more but I just tried to connect using Forklift and it displayed both “home” and “homes” and if I ask for the url of the former I just get
sftp://ipaddress/home
so yeah, that would have been a clue.
I’m having the same issue - but with my own NAS which runs a mix of Debian testing and OpenMediaVault. I’ve set up a backup using borgbackup, which is working fine, but I wanted to try Duplicati just for fun (well actually it supports Amazon Drive out of the box, which is what I’m looking for).
I have a ‘backup’ user on my NAS who has a home directory residing on /export/NAS/Backup - borgbackup is just putting its files in a directory relative to the home directory of that user.
If I try doing the same thing with Duplicati I get the ‘Failed to connect: No such file’ error. Just to be clear, I’m using SSH file transfer (SFTP).
I was trying with ‘duplicati/pcname’ or ‘/duplicati/pcname’ or ‘~/duplicati/pcname’ or ‘./duplicati/pcname’
I also tried connecting with FileZilla using SFTP which works fine, I can access the folder, create stuff, delete stuff. Just like borgbackup does as well.
I also created the directory and tried again with duplicati - to no avail. If I leave the directory empty it says okay but ends up with a permission error. Troubleshooting is hard because I have no idea where Duplicati is trying to go.
Solution: This still seems like a bug in Duplicati:
Put
/home/../export/NAS/Backup/duplicati/pcname
into the folder.
I find that rather strange and completely counter intuitive compared to how every other tool at my disposal handles this.
Hello Wim,
Could you maybe elaborate a little bit on that, because I still can’t make it connect. I have a Synology NAS and I entered the share and folder now like: /backup/documents
Not quite sure what you mean with: “provide the path as follows: /home/duplicati
instead of:
/volume1 or /var”
Thans in advance 
Hello @Zonal, welcome to the forum!
Can you clarify what you mean by “can’t make it connect”? Do you mean you can’t get to the web based UI, can’t get Duplicati to see the paths you want to become a up, can’t get the job to connect to the backend, or something else?
Did you follow I this guides for your setup? If so, if like to figure out where it didn’t work for you.
Hey Jon,
Thanks for the quick response and sorry for the lack of information. I wasn’t actually trying to install Duplicati on my Synology NAS, I’m running it on Windows and am trying to back up to a Synology NAS through SFTP (SSH).
Now I have setup a FTP server on my NAS and that works fine, but when I try to setup a back up profile through SFTP and click “Test connection” I get the following message:
“No certificate was specified previously, please verify with the server administrator that the key is correct: ssh-rsa 2048 ??:??:??:??:??:??:??:??:??:??:??:??:??:??:??:?? Do you want to approve the reported host key?”
I ‘blanked’ out the key for posting it on an open forum, not sure if that’s needed in this case…
Then I click ‘Yes’ and I get the message: “The folder /backup/SFTPtest does not exist. Create it now?”
I click ‘Yes’ again and then I get the error: “Failed to connect: No such file”
It doesn’t make any difference if the folder was already created beforehand. I keep receiving this error. So I saw the possible solution mentioned by Wim, but I’m not quite sure what he means. That’s why I asked if he or somebody might be able to clear that up!
Thanks in advance!
I’m no longer using my NAS as a destination, so can’t check.
My suggestion would be to use a ftp client, connect to your machine, browse to the folder you want Duplicati to use, and see if the client exposes the path. That’s the path to use.
This is how I found the path to use.
Regards,
Wim
I’m so stupid… forward slash instead of backslash. Windows uses backslash so I forgot…
Thanks for the quick reply though!
Just in case somebody is struggling with configuring SFTP on a QNAP: the folder is /share/backup, where backup is an example root folder in the QNAP File station for your backup.