FileZilla uploading multiple large files parallel

Hi,

I have found an issue when I am try to modify the default sample script:

What I have done? I have created an dotnet core web app using the following Program.cs code, which I have take from the quick start:

namespace WebApplication1
{
    internal class HostedFtpService : IHostedService
    {
        private readonly IFtpServerHost _ftpServerHost;

        /// <summary>
        /// Initializes a new instance of the <see cref="HostedFtpService"/> class.
        /// </summary>
        /// <param name="ftpServerHost">The FTP server host that gets wrapped as a hosted service.</param>
        public HostedFtpService(
            IFtpServerHost ftpServerHost)
        {
            _ftpServerHost = ftpServerHost;
        }

        /// <inheritdoc />
        public Task StartAsync(CancellationToken cancellationToken)
        {
            return _ftpServerHost.StartAsync(cancellationToken);
        }

        /// <inheritdoc />
        public Task StopAsync(CancellationToken cancellationToken)
        {
            return _ftpServerHost.StopAsync(cancellationToken);
        }
    }
    public class Program
    {
        public static void Main(string[] args)
        {
            CreateWebHostBuilder(args).Build().Run();
        }

        public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .ConfigureServices(
                    services =>
                    {
                        // Add FTP server services
                        // DotNetFileSystemProvider = Use the .NET file system functionality
                        // AnonymousMembershipProvider = allow only anonymous logins
                        services
                            .AddFtpServer(
                                builder => builder
                                    .UseDotNetFileSystem()
                                    .EnableAnonymousAuthentication());

                        // Configure the FTP server
                        services.Configure<FtpServerOptions>(opt => opt.ServerAddress = "*");

                        // use %TEMP%/TestFtpServer as root folder
                        services.Configure<DotNetFileSystemOptions>(opt => opt
                            .RootPath = Path.Combine(Path.GetTempPath(), "TestFtpServer"));

                        Console.WriteLine("PATH: " + Path.GetTempPath());

                        // Add the FTP server as hosted service
                        services
                            .AddHostedService<HostedFtpService>();
                    })
                .UseStartup<Startup>();
    }
}

What is the problem? When I connect 1 client with 8 uploads at once to my FTP server which runs in an Ubuntu server on Azure and every client starts to upload a file bigger than 300MB then for most uploads will stuck at 100% in FileZilla and run into a timeout:

08:26:00    Befehl: STOR can-it-be-done-in-react-native-master.zip
08:26:00    Antwort:    150 Opening connection for data transfer.
08:27:25    Fehler: Zeitüberschreitung der Verbindung nach 20 Sekunden Inaktivität // Timeout
08:27:25    Fehler: Dateiübertragung fehlgeschlagen nach Übertragung von 247.897.864 Bytes in 401 Sekunden
08:27:25    Status: Verbindung zum Server getrennt

I would be very happy if you could help me with this issue!

Best, Sebastian

I'm unable to reproduce the problem. Can you please enable server-side logging? You can do this by:

1. Add `Microsoft.Extensions.Logging.Console` to your project (skip if already added)

This is the new QuickStart.AspNetCoreHost.csproj file:

<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp3.0</TargetFramework>
    <AspNetCoreHostingModel>InProcess</AspNetCoreHostingModel>
    <IsPackable>false</IsPackable>
    <SuppressNETCoreSdkPreviewMessage>true</SuppressNETCoreSdkPreviewMessage>
  </PropertyGroup>

  <ItemGroup>
    <ProjectReference Include="..\..\src\FubarDev.FtpServer.FileSystem.DotNet\FubarDev.FtpServer.FileSystem.DotNet.csproj" />
    <ProjectReference Include="..\..\src\FubarDev.FtpServer\FubarDev.FtpServer.csproj" />
  </ItemGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="3.0.0" />
  </ItemGroup>

</Project>

2. Enable logging in Program.cs

Change the CreateWebHostBuilder function to:

        public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .ConfigureLogging(lb => {
                    lb.AddConsole();
                })
                .ConfigureServices(
                    services =>
                    {
                        services
                           .AddFtpServer(
                                builder => builder
                                   .UseDotNetFileSystem()
                                   .EnableAnonymousAuthentication())
                           .AddHostedService<HostedFtpService>();
                    })
                .UseStartup<Startup>();

3. Start the server

sudo ASPNETCORE_ENVIRONMENT=Development ./QuickStart.AspNetCore > out.log 2>&1

4. Clean-up the log

Remove any sensitive information (if there is any at all), like server IP, user name, etc...

5. Provide additional information

FTP server nuget version
OS name and version
... whatever else might be important

FubarDevelopment / FtpServer