Thanks for the stack trace. Maybe the developer can make a guess.
The one thing that seems clear is that the remote closed connection.
Google for socket exception 10054 gives many things it might mean.
A more definite analysis might need protocol analysis that isn’t likely.
I’m assuming you’re on an encrypted https connection over Internet?
Rather than blame the remote, question is why it decided to go away.
Possibly Duplicati did something it disliked. Maybe it got tired of work.
Some systems do throttle (slow work) after one has done lots of work.
Is this a private server, or some company maybe limiting your usage?
Are you seeing any pattern? Does it fail randomly, or at typical times?
Have you tried a smaller volume size? A gigabyte seems rather large.
You could also increase all the timeouts possible to see if that helps it.
is what I thought the rule was, but dev might know. If you configure huge, you might get huge. Unclear if there’s a bug involved, but the dev might comment. I’d have hoped huge is on disk.
EDIT 1:
If you want a shot-in-the-dark of increasing timeouts, CLI help for webdav says defaults are:
--short-timeout = 30s
The timeout in seconds for short operations like delete and create folder
--list-timeout = 10m
The timeout in seconds for listing files and folders
--read-write-timeout = 30s
The timeout in seconds for read and write operations. If no activity is detected in this interval, a timeout error is raised
and you could try raising all of them to some number of minutes longer than usually needed.