Question

我有一个NET Core Console Application，其中一个socket绑定到一个port。
我已经 docker 修改了此应用程序，并尝试公开绑定的port。
当我使用docker attach [instance]时，程序会正确显示其输出。
但是，当尝试与Telnet连接时，出现错误：

错误

$ telnet 127.0.0.1 20001
Connecting To 127.0.0.1...Could not open connection to the host, on port 8806: Connect failed

.NET服务器

class Program {

    public const int BUFFER_SIZE = 1024;
    public const int EXPOSED_PORT = 20001;
    public const string ADDRESS = "127.0.0.1";
    public const int MAX_CONNECTIONS = 1;

    public static ReadOnlyMemory<byte> CreateMessage(ReadOnlyMemory<byte>request) {
        Memory<byte> response= Encoding.UTF8.GetBytes($"Response from Daemon:{DateTime.Now.ToString()}");
        ///------code------//
        return response;
    }

    static async Task Main(string[] args) {

        Memory<byte> buffer = ArrayPool<byte>.Shared.Rent(BUFFER_SIZE);

        using (Socket serverSocket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)) {
            serverSocket.Bind(new IPEndPoint(IPAddress.Parse(ADDRESS), EXPOSED_PORT));
            Console.WriteLine($"Server started at {DateTime.Now.ToShortTimeString()} \r\nListening on port{EXPOSED_PORT}");
            serverSocket.Listen(MAX_CONNECTIONS);

            var client =await serverSocket.AcceptAsync();
            while (true) {
                int rxCount =await  client.ReceiveAsync(buffer, SocketFlags.None);
                if ((char) buffer.Span[0] == 'x'){
                    break;
                }
                await client.SendAsync(CreateMessage(buffer.Slice(0, rxCount)), SocketFlags.None);
            }
        }
        ArrayPool<byte>.Shared.Return(buffer.ToArray());

    }
}

Dockerfile

FROM microsoft/dotnet:latest
WORKDIR /app
COPY ./bin/Release/netcoreapp2.1/publish .
ENTRYPOINT [ "dotnet","DockerContainerDaemon.dll" ]
EXPOSE 20001

docker和构建命令脚本

dotnet build -c Release
dotnet publish
docker build --build-arg Port=20001 -t  daemon  .
docker stop inst1
docker rm inst1
docker run --name inst1 -p 20001:20001 -d daemon

运行docker -ps -a

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                      NAMES
f675c3e502ad        daemon              "dotnet DockerContai…"   5 seconds ago       Up 3 seconds        0.0.0.0:20001->20001/tcp   inst1

PS 正如某人指出的那样，我尝试使用127.0.0.1中的0.0.0.0和.NET Application进行曝光。无济于事。

Answer 1

尝试将应用程序绑定到0.0.0.0，而不是127.0.0.1。这样可以解决您的问题。

通过telnet连接到docker容器

1 个答案: