Hello @wtuvell, welcome to the forum!
I suspect the “Insertion failed because the database is full database or disk is full” message (hmm…might need to re-word that) is coming from SQLite as mentioned here in which case you might need to set the TMPDIR environment variable:
It’s also possible the database file in question is being stored on a full partition, though normally I’ve only see that with Dockers and Synology NAS devices:
As for /tmp usage, keep in mind that Duplicati will create up to 4 dblock (archive Volumes) in preparation for upload, so if your “Upload volume size” is large (say 500MB), you could be running out of temp space due to needing 2GB for waiting-to-be-uploaded files.
If that’s the case, you can resolve it by setting a smaller --dblock (“Upload volume”) size and / or adjusting the --asynchronous-upload-limit:
--asynchronous-upload-limit(default4)
When performing asynchronous uploads, Duplicati will create volumes that can be uploaded. To prevent Duplicati from generating too many volumes, this option limits the number of pending uploads. Set to zero to disable the limit