FTP Error causes Duplicati to crash

Support
1

Running Duplicati - 2.1.0.2_beta on Windows 11 and mostly it seems ok.

I tested a restore and the web GUI seemed to reload and the restore didn’t complete. I ran it again after this reload and it restored files correctly.

I’ve checked in the logs and I can see the following

[Information-Duplicati.Library.Main.BasicResults-BackendEvent]: Backend event: List - Retrying:  ()

Application: Duplicati.Server.exe
CoreCLR Version: 8.0.624.26715
.NET Version: 8.0.6
Description: The process was terminated due to an unhandled exception.
Exception Info: System.TimeoutException: Timed out trying to read data from the socket stream!
   at FluentFTP.FtpSocketStream.ReadAsync(Byte[] buffer, Int32 offset, Int32 count, CancellationToken token)
   at FluentFTP.FtpSocketStream.ReadLineAsync(Encoding encoding, CancellationToken token)
   at FluentFTP.Client.BaseClient.BaseFtpClient.FluentFTP.IInternalFtpClient.GetReplyInternal(CancellationToken token, String command, Boolean exhaustNoop, Int32 timeOut, Boolean useSema)
   at FluentFTP.Client.BaseClient.BaseFtpClient.FluentFTP.IInternalFtpClient.GetReplyInternal(CancellationToken token, String command)
   at FluentFTP.Client.BaseClient.BaseFtpClient.FluentFTP.IInternalFtpClient.CloseDataStreamInternal(FtpDataStream stream, CancellationToken token)
   at FluentFTP.Client.BaseClient.BaseFtpClient.FluentFTP.IInternalFtpClient.CloseDataStreamInternal(FtpDataStream stream, CancellationToken token)
   at FluentFTP.FtpDataStream.CloseAsync(CancellationToken token)
   at FluentFTP.FtpSocketStream.<>c__DisplayClass74_0.<<ReadAsync>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__128_1(Object state)
   at System.Threading.QueueUserWorkItemCallback.Execute()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()
   at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()


Faulting application name: Duplicati.Server.exe, version: 2.1.0.2, time stamp: 0x66470000
Faulting module name: KERNELBASE.dll, version: 10.0.26100.2454, time stamp: 0x398a1cce
Exception code: 0xe0434352
Fault offset: 0x00000000000c837a
Faulting process id: 0x777C
Faulting application start time: 0x1DB555A9572C7D5
Faulting application path: c:\Program Files\Duplicati 2\Duplicati.Server.exe
Faulting module path: C:\WINDOWS\System32\KERNELBASE.dll
Faulting package full name: 


Attempting to restart server process: c:\Program Files\Duplicati 2\Duplicati.Server.exe

Duplicati did restart itself correctly and after that restart it was fine but I thought I’d raise it as it seems odd.

2

Thanks!

I think this has been fixed in 2.1.0.103. It is also reported here:

3

Thanks for the update.

Apologies for the duplicate posting. I did a quick search of the forum beforehand.

I’ll give it a test when the next beta is released thanks :smile:

4

Did you perform some test with the recent betas? Any idea when this fix is released in the stable branch?
I’m having this issue for quite awhile now, effectively not being able to backup my stuff anymore (EDIT: without leaving stable, which I’m kind hesitant)

5

v2.1.0.102_canary_2024-12-12

Upgraded FluentFTP to fix a crash on socket timeout

v2.1.0.3_beta_2025-01-22

v2.1.0.4_stable_2025-01-31

v2.1.0.5_stable_2025-03-04

are still on the older FluentFTP version 50.1. The dev might comment on 52.0 plan.

Meanwhile, there are no recent betas with this fix to test. Ample higher-risk Canary.

Downgrade from 2.1.0.2 to 2.0.8.1 might be an option. Do you know if it ran for you?

6

Unfortunately, I don’t exactly know whether I used that version before. I am quite hesitant to try that since I have to change a lot on the database for downgrading, and I don’t want to lose my data.
Anyways, thank you for your reply!