What is the correct action for this fileset warning?

My last backup gave me this warning: 2021-03-15 14:42:45 -06 - [Warning-Duplicati.Library.Main.Operation.Backup.UploadSyntheticFilelist-MissingTemporaryFilelist]: Expected there to be a temporary fileset for synthetic filelist (334, duplicati-i15b8eceb833d488e979c69c3bdaf4835.dindex.zip.aes), but none was found?

My question is, what should I do next? Am I missing files? Do I just run another backup? Do I need to do some other action? I’ve seen a handful of posts on this topic, but it wasn’t clear what the end user should do on such a warning.

As for what caused this warning, I have a setup where the remote end prevents file appends or file deletes (using Linux’s chattr +i and also using appropriate Duplicati settings). It works great, except if a backup is interrupted. This time I simply turned back on appending and deletion (chattr -i), re-ran the backup, and got the warning.

An update. A scheduled backup ran, and I received no errors or warnings.

On that one, ignore it. The buggy code ran at start of backup, then that backup and next one ran, right?
All you’re missing is probably a “feature” trying to make another backup version of state as of interrupt, which you’re now way beyond. Next Beta should successfully build that synthetic filelist, when needed.

Interrupting backups in should ideally only be done by “Stop after current file”. Next Beta makes “Stop now” safe (it’s hoped). Any harder interruption runs some risk of damage, so try to avoid those…

Thanks again for the reply.

I don’t manually interrupt. Most of my backups are scheduled to run at 2:00 AM, which I’ve found is when Comcast does most of their planned maintenance work…