局域网内其他机器连接AspNetCore SignalR Server失败求助

问题现象 #

本地使用localhost访问SignalR Hub可正常建立连接，但局域网内其他机器通过服务器IP/机器名访问时，出现连接超时错误：

A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. (192.168.10.120:80)

服务器端代码（HubServer.Program.cs） #

public static void Main(string[] args)
{

  getRegistrySettings();

  WebApplicationBuilder builder = WebApplication.CreateBuilder(args);

  // Add services to the container.
  builder.Services.AddRazorPages();
  builder.Services.AddServerSideBlazor();
  builder.Services.AddSingleton<WeatherForecastService>();
  builder.Services.AddResponseCompression(opts =>
  {
    opts.MimeTypes = ResponseCompressionDefaults.MimeTypes.Concat(
        new[] { "application/octet-stream" });
  });

  builder.Services.AddCors(options =>
  {
    options.AddPolicy("CORSPolicy", builder =>
    builder.AllowAnyMethod().AllowAnyHeader().AllowCredentials().SetIsOriginAllowed((hosts) => true));
  });


  WebApplication app = builder.Build();

  // Configure the HTTP request pipeline.
  if (!app.Environment.IsDevelopment())
  {
    app.UseExceptionHandler("/Error");
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts();
  }

  //CORS need to be enabled for calling SignalR service 
  app.UseCors("CORSPolicy");

  //app.UseHttpsRedirection();

  app.UseStaticFiles();

  app.UseRouting();

  app.MapBlazorHub();

  app.MapHub<MCHub>("/mchub");

  //app.MapFallbackToPage("/_Host");

  app.Run();
}

客户端WPF代码 #

public MainWindow()
{
    InitializeComponent();

    //const string url = "http://localhost:5289/mchub";
    const string url = "http://192.168.10.120/mcsrhub/mchub";
    var queryString = new Dictionary<string, string>
      {
        { "CreatedBy", "me" },
        { "UserId", "1234" },
        { "MachineName", Environment.MachineName }
      };

    var newUrl = new Uri(QueryHelpers.AddQueryString(url, queryString));

    connection = new HubConnectionBuilder()
        .WithUrl(newUrl) //"http://localhost:5289/mchub") //5181/chathub")
        .WithAutomaticReconnect()
        .Build();

    connection.Reconnecting += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Attempting to reconnect...";
            messages.Items.Add(newMessage);
        });

        return Task.CompletedTask;
    };

    connection.Reconnected += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Reconnected to the server";
            messages.Items.Clear();
            messages.Items.Add(newMessage);
        });

        return Task.CompletedTask;
    };

    connection.Closed += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Connection Closed";
            messages.Items.Add(newMessage);
            openConnection.IsEnabled = true;
            sendMessage.IsEnabled = false;
        });

        return Task.CompletedTask;
    };
}

private async void openConnection_Click(object sender, RoutedEventArgs e)
{
    connection.On<string, string>("ReceiveMessage", (user, message) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = $"{user}: {message}";
            messages.Items.Add(newMessage);
        });
    });

    try
    {

        await connection.StartAsync();
        messages.Items.Add("Connection Started");
        openConnection.IsEnabled = false;
        sendMessage.IsEnabled = true;
    }
    catch (Exception ex)
    {
        messages.Items.Add(ex.Message);
    }
}

private async void sendMessage_Click(object sender, RoutedEventArgs e)
{
    try
    {
        await connection.InvokeAsync("SendMessage",
            "WPF Client", messageInput.Text);
    }
    catch (Exception ex)
    {
        messages.Items.Add(ex.Message);
    }
}

已尝试操作 #

• 关闭两台机器的AVG杀毒软件
• 确认服务器80端口开放
• 添加CORS配置（允许任意方法、头部、凭据，允许所有来源）

补充信息 #

服务器由IIS托管

排查与解决方案 #

1. 检查IIS站点绑定 #

• 确保IIS站点绑定包含局域网可访问的IP（192.168.10.120），而非仅localhost或127.0.0.1
• 确认绑定端口为80，且无其他服务占用该端口

2. 服务器防火墙配置 #

• 检查Windows Defender防火墙，添加入站规则允许80端口的HTTP流量
• 确保规则覆盖局域网所在的专用网络配置文件

3. 验证站点路径有效性 #

• 在服务器浏览器中访问http://192.168.10.120/mcsrhub/mchub，确认能返回SignalR协商响应（非404错误）
• 检查IIS中/mcsrhub虚拟目录是否正确映射到项目物理路径

4. 确认ASP.NET Core模块配置 #

• 确保IIS已安装对应.NET版本的ASP.NET Core托管模块
• 站点应用程序池的.NET CLR版本需设置为无托管代码

5. 网络连通性测试 #

• 在客户端执行ping 192.168.10.120，确认基础网络连通
• 用Test-NetConnection 192.168.10.120 -Port 80测试端口是否真正可达

6. 强制SignalR传输方式（可选） #

若上述步骤无效，可强制客户端使用WebSocket或长轮询，避免协议受阻：

connection = new HubConnectionBuilder()
    .WithUrl(newUrl, options =>
    {
        options.Transports = HttpTransportType.WebSockets | HttpTransportType.LongPolling;
    })
    .WithAutomaticReconnect()
    .Build();

内容的提问来源于stack exchange，提问作者David