I’ve been running a QNAP port of UrBackup and recently ran into an issue, which I believe I’ve figured out.
After running for a while it eventually gave me an error indicating that the backup folder was full despite there still being plenty of space.
I had setup the folder as a share which I’d named UrBackup. When accessing the NAS unit via SSH the share is located at /share/UrBackup, though this is actually a symlink to the real path.
I noticed that when I listed the contents of this directory via ssh terminal, not everything was being shown compared to browsing to the smb share. As such, I started searching around for the actual direct path that would show all the contents. I found this path at /share/ZFS##_DATA, where ## is a number automatically generated by QuTS when I initially configured the UrBackup share. Listing the contents of this folder showed all the contents as expected.
Changing the folder path configured in the UrBackup server to the more direct one resolved the insufficient space error and allowed clients to resume backing up to the server.
Figured I’d share my findings in case anyone else is trying to run the QNAP port and come across the same error. I expect it’s entirely an artifact of how QNAP does things, and not something that would show up on other platforms.