Docker 容器之间的 SCTP 连接挂起

Question

我在设置 Docker 容器、通过 SCTP 进行通信时遇到了一些问题。所有相关文件都在下面。

运行 docker-compose up 后，输出如下：

$ docker-compose up
Starting server ... done
Starting client ... done 
Attaching to server, client
server    | Opening SctpServerChannel...
server    | Binding to: server/172.18.0.2:3868
server    | Waiting for new connection....
client    | Opening SctpChannel...
client    | Binding to: client/172.18.0.3:0
client    | Connecting to: server/172.18.0.2:3868

客户端永远不会成功连接到服务器（同样，服务器永远不会收到客户端的连接）。

src/SctpClient.java

import java.io.IOException;
import java.net.InetSocketAddress;

import com.sun.nio.sctp.SctpChannel;

public class SctpClient 
{
    public static void main(String[] args) throws IOException 
    {
        String[] parts = args[0].split(":");
        InetSocketAddress local = new InetSocketAddress(parts[0], Integer.parseInt(parts[1]));

        parts = args[1].split(":");
        InetSocketAddress remote = new InetSocketAddress(parts[0], Integer.parseInt(parts[1]));

        System.out.println("Opening SctpChannel...");
        SctpChannel client = SctpChannel.open();

        System.out.println("Binding to: "+local);
        client.bind(local);

        System.out.println("Connecting to: "+remote);
        if (client.connect(remote))
            System.out.println("Connected!");           
        else
            System.out.println("Connection failed!");
    }
}

src/SctpServer.java

import java.io.IOException;
import java.net.InetSocketAddress;

import com.sun.nio.sctp.SctpChannel;
import com.sun.nio.sctp.SctpServerChannel;

public class SctpServer 
{
    public static void main(String[] args) throws IOException 
    {
        String[] parts = args[0].split(":");
        InetSocketAddress local = new InetSocketAddress(parts[0], Integer.parseInt(parts[1]));

        System.out.println("Opening SctpServerChannel...");
        SctpServerChannel server = SctpServerChannel.open();

        System.out.println("Binding to: "+local);
        server.bind(local);

        System.out.println("Waiting for new connection....");
        while (true)
        {
            SctpChannel client = server.accept();
            if (client == null)
                System.out.println("Connection failed!");
            else
                System.out.println("Connected: "+client.getRemoteAddresses());
        }
    }
}

docker-compose.yml

version: '3.7'
services:

        server:
                build:
                        context: .
                        dockerfile: Dockerfile-Server
                image: server
                container_name: server
                restart: unless-stopped
                environment:
                        - LOCAL_IFACE=server:3868
                ports:
                        - "3868:3868/sctp"
                networks:
                        - sctp

        client:
                build:
                        context: .
                        dockerfile: Dockerfile-Client
                image: client
                container_name: client
                restart: unless-stopped
                environment:
                        - LOCAL_IFACE=client:0
                        - REMOTE_IFACE=server:3868
                networks:
                        - sctp
                depends_on:
                        - server
                stdin_open: true
                tty: true

networks:
        sctp:
                name: sctp

Dockerfile-客户端

FROM openjdk:11-jdk
RUN apt-get update -y && apt-get install lksctp-tools -y && apt-get clean
WORKDIR /opt
COPY src/SctpClient.java .
CMD java SctpClient.java $LOCAL_IFACE $REMOTE_IFACE

Dockerfile 服务器

FROM openjdk:11-jdk
RUN apt-get update -y && apt-get install lksctp-tools -y && apt-get clean
WORKDIR /opt
COPY src/SctpServer.java .
CMD java SctpServer.java $LOCAL_IFACE

大家有什么建议吗？

Answer 1

我想经过这么长时间我应该发布我是如何工作的：

有趣的是，从 docker-compose.yml 中删除端口的发布允许容器之间的 SCTP 工作。这与 TCP 的工作方式不同。

此外，如果您希望主机网络上的应用通过 SCTP 与容器通信，则必须使用主机网络。与 TCP 的工作方式相比，这也有所不同。

在原始帖子发布时，似乎 SCTP 支持在 docker 中仍然很原始。