“deep” means the number of folders, e.g. reading path from left to right. When did path stop working?
Actually, I can sort of see this in some of the 20 messages where it starts failing then lower paths fail.
Failed to create folder: \"/media/BACKUP_DIR/.local/share/Trash/files/cd ../\", message: Invalid argument"
might have been the first, but messages are incomplete so I don’t know if the files level got created.
FAT has character restrictions, and so might have choked on this style of (I think) Java-encoded string:
Failed to create folder: \"/media/BACKUP_DIR/.java/.userPrefs/_!()!bw\"i!'8!d!\"i!(`!a@\"s!'@!~@\"y!#4!^@\"h!'k!bg\"'!()!}@\"t!'`=/\", message: Invalid argument"
I suppose you can try getting that quoted for a shell to see if you can make such a folder name by hand.
Does that mean you deleted a current directory like the above, or it actually was created by the restore?
I wasn’t sure if there was a problem with the system. If system is alive and well and has room, restore to Linux filesystem instead of FAT and see if it does better. Linux filesystems have few forbidden characters.
Having restored (might need further work…), see if you can cp --archive or something onto USB drive.
Yes. It should be all set to run as a systemd service as root, but it will probably take some systemctl work.
Installing Duplicati on Linux covers it, but maybe not ideally according to Part of installation fails on Ubuntu.
If you know systemctl it’s probably something like systemctl status duplicati to see where you are, then maybe an enable and start if you were starting from nothing, but because you’re already running as non-root user, you probably want to stop Duplicati and move some databases. Currently they’re located in ~/.config/Duplicati and ~ will be ~root after you’re root. I would suggest DB copy rather than moves initially, because I don’t have an exact Linux procedure. You can probably do this step by step too. Copying current Duplicati-server.sqlite in your directory (after Duplicati shutdown) to root area should let you start Duplicati, however it will use per-job databases in your directory. This should work, but what if that ever gets deleted?
To move all your job databases after getting up as root, you can probably use the Database screen to edit Local database path to new ~root location, then click the newly-blue Move existing database button.
Migrating from User to Service install on Windows has a similar method. Directions also describe how to retain the Tray Icon if you have one now and like it. Because the root start-at-boot Duplicati is just a server that doesn’t put the Tray Icon on your desktop, you can still start Tray Icon, but tell it --no-hosted-server.
Another migration caveat is that if your current backup source was done in the User data section (e.g. My Documents), you might need to change that to something in Computer so that it’s not dependent on a user.