在 Docker 中将 Java Spring 应用程序连接到 ScyllaDB 集群时出错答案

Datacenter: DC1 =============== Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- Address Load Tokens Owns Host ID Rack UN 172.19.0.3 205.31 KB 256 ? c387bd38-cf37-4c70-a8a3-db586f6410c4 Rack1 UN 172.19.0.2 101.61 KB 256 ? 89dda41e-70c5-43a5-a4a7-ce126007a1e1 Rack1 UN 172.19.0.4 210.34 KB 256 ? 58dfe868-a7ac-47a5-b3e9-dae610ef0bc9 Rack1 CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES b90d0357abee scylladb/scylla:4.5.0 "/docker-entrypoint.…" 2 minutes ago Up 2 minutes 22/tcp, 7000-7001/tcp, 9042/tcp, 9160/tcp, 9180/tcp, 10000/tcp scylla-node2 19f19cb2e631 scylladb/scylla:4.5.0 "/docker-entrypoint.…" 2 minutes ago Up 2 minutes 22/tcp, 7000-7001/tcp, 9042/tcp, 9160/tcp, 9180/tcp, 10000/tcp scylla-node3 c98b0b1aa018 scylladb/scylla:4.5.0 "/docker-entrypoint.…" 2 minutes ago Up 2 minutes 22/tcp, 7000-7001/tcp, 9042/tcp, 9160/tcp, 9180/tcp, 10000/tcp scylla-node1

Cluster cluster = Cluster.builder().addContactPoints("172.19.0.3", "172.19.0.2", "172.19.0.4") .build(); System.out.println("Connected to cluster " + cluster.getMetadata().getClusterName());

2022-05-08 18:00:02.928 INFO 4760 --- [ restartedMain] com.datastax.driver.core.NettyUtil : Did not find Netty's native epoll transport in the classpath, defaulting to NIO. 2022-05-08 18:00:09.149 WARN 4760 --- [r1-nio-worker-0] com.datastax.driver.core.Connection : Error creating netty channel to /172.19.0.4:9042 io.netty.channel.ConnectTimeoutException: connection timed out: /172.19.0.4:9042 at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe$1.run(AbstractNioChannel.java:261) ~[netty-transport-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.PromiseTask.runTask(PromiseTask.java:98) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.ScheduledFutureTask.run(ScheduledFutureTask.java:170) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.AbstractEventExecutor.safeExecute$$$capture(AbstractEventExecutor.java:164) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:469) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:503) [netty-transport-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:986) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) [netty-common-4.1.75.Final.jar:4.1.75.Final] at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) [netty-common-4.1.75.Final.jar:4.1.75.Final] Exception in thread "restartedMain" java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) Caused by: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /172.19.0.4:9042 (com.datastax.driver.core.exceptions.TransportException: [/172.19.0.4:9042] Cannot connect), /172.19.0.3:9042 (com.datastax.driver.core.exceptions.TransportException: [/172.19.0.3:9042] Cannot connect), /172.19.0.2:9042 (com.datastax.driver.core.exceptions.TransportException: [/172.19.0.2:9042] Cannot connect)) at com.datastax.driver.core.ControlConnection.reconnectInternal(ControlConnection.java:270) at com.datastax.driver.core.ControlConnection.connect(ControlConnection.java:109) at com.datastax.driver.core.Cluster$Manager.negotiateProtocolVersionAndConnect(Cluster.java:1921) at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1832) at com.datastax.driver.core.Cluster.getMetadata(Cluster.java:476) at com.dt.package.ScyllaConnection.connect_and_query(ScyllaConnection.java:15) at com.dt.package.MyApp.main(MyApp.java:12) ... 5 more

scylla-node2: container_name: scylla-node2 image: scylladb/scylla:4.5.0 restart: always command: --seeds=scylla-node1,scylla-node2 --smp 1 --memory 750M --overprovisioned 1 --api-address 0.0.0.0 volumes: - "./scylla/scylla.yaml:/etc/scylla/scylla.yaml" - "./scylla/cassandra-rackdc.properties.dc1:/etc/scylla/cassandra-rackdc.properties" networks: web:

【解决方案1】：

问题可能是因为您尝试使用其 docker 内部 IP 地址连接到 ScyllaDB 节点。

如果您需要从内部 docker 网络外部访问您的节点，您需要正确地向 docker 主机公开适当的端口。

使用 docker compose，您可以使用 ports 字段导出容器端口。例如：

  scylla-node2:
    container_name: scylla-node2
    image: scylladb/scylla:4.5.0
    restart: always
    command: --seeds=scylla-node1,scylla-node2 --smp 1 --memory 750M --overprovisioned 1 --api-address 0.0.0.0
    ports:
      - 9043:9042
    volumes:
      - "./scylla/scylla.yaml:/etc/scylla/scylla.yaml"
      - "./scylla/cassandra-rackdc.properties.dc1:/etc/scylla/cassandra-rackdc.properties"
    networks:
      web:

在示例中，我们将容器端口 9042 暴露给主机端口 9043。

您将需要与其余节点类似的配置：您为所有节点使用相同的主机，因此您需要为每个节点选择不同的端口。

  scylla-node1:
    ...
    ports:
      - 9042:9042
    ...
  scylla-node2:
    ...
    ports:
      - 9043:9042
    ...
  scylla-node3:
    ...
    ports:
      - 9044:9042
    ...

不同的节点将共享同一个主机，即运行 docker 容器的主机。要从 Spring 应用程序连接到它们，您需要以下内容：

Cluster cluster =
  Cluster.builder()
    .addContactPointsWithPorts(
      new InetSocketAddress("127.0.0.1", 9042),
      new InetSocketAddress("127.0.0.1", 9043),
      new InetSocketAddress("127.0.0.1", 9044)
    );

System.out.println("Connected to cluster " + cluster.getMetadata().getClusterName());

请注意在代码中使用方法addContactPointsWithPorts 而不是addContactPoints。

【讨论】：

感谢jccampanero的详细解释！看来我还有一些关于 docker 的学习要做。我按照你的解释改了代码，现在集群连接正常了。
抱歉，Gustavo 回复晚了。不客气。我很高兴听到建议的代码可以正常工作。祝你在 Docker 学习道路上一切顺利。如果您认为我可以提供帮助，请不要犹豫再次与我联系，如果可能，我很乐意为您提供帮助。

【解决方案2】：

我也遇到了同样的问题，但是设置不同的端口仍然没有解决。

【讨论】：