I’m not very familiar with how this works, but I think the renames are part of recovery from a failed transfer, which makes some sense if one wants a clean retry instead of worrying about who-knows-what-got-written.
–debug-retry-errors might show you error messages produced each time, instead of only after retries end. You can also get a slightly better log with the –log-file option. For example, it will show times to the second. Knowing the error forcing a retry may help. Here’s a B2 example. You might need –log-file-log-level=Retry:
2018-11-17 08:05:55 -05 - [Retry-Duplicati.Library.Main.Operation.Common.BackendHandler-RetryPut]: Operation Put with file duplicati-b26c17dafffe84613ac6d791ea6d598a5.dblock.zip.aes attempt 1 of 5 failed with message: Unable to read data from the transport connection: The connection was closed.
System.IO.IOException: Unable to read data from the transport connection: The connection was closed.
at System.Net.ConnectStream.IOError(Exception exception, Boolean willThrow)
at System.Net.ConnectStream.InternalWrite(Boolean async, Byte[] buffer, Int32 offset, Int32 size, AsyncCallback callback, Object state)
at System.Net.ConnectStream.Write(Byte[] buffer, Int32 offset, Int32 size)
at Duplicati.Library.Utility.Utility.CopyStream(Stream source, Stream target, Boolean tryRewindSource, Byte[] buf)
at Duplicati.Library.Backend.Backblaze.B2.<>c__DisplayClass24_0.<Put>b__1(AsyncHttpRequest req)
at Duplicati.Library.JSONWebHelper.GetJSONData[T](String url, Action`1 setup, Action`1 setupbodyreq)
at Duplicati.Library.Backend.Backblaze.B2.Put(String remotename, Stream stream)
at Duplicati.Library.Main.Operation.Common.BackendHandler.<DoPut>d__23.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Duplicati.Library.Main.Operation.Common.BackendHandler.<>c__DisplayClass13_0.<<UploadFileAsync>b__2>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Duplicati.Library.Main.Operation.Common.BackendHandler.<DoWithRetry>d__21`1.MoveNext()
Because you’re on Wasabi, I’d note that there might have been some odd technical issues starting Nov. 23 however it’s not clear whether it could have caused what you’re seeing, but maybe your issue will go away.