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如果我在连接完成后关闭 cassandra 集群，我正在使用客户端写入 cassandra（api：com.datastax.driver.core）。我的日志中出现以下错误

2015-11-05 12:08:21,667 ERROR [Reconnection-1] com.datastax.driver.core.ControlConnection - [Control connection] Cannot connect to any host, scheduling retry in 1000 milliseconds
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2015-11-05 14:15:24,847 DEBUG [Reconnection-0] com.datastax.driver.core.Connection - Connection[/10.75.43.251:9042-24, inFlight=0, closed=false] Error connecting to /10.75.43.251:9042 (Connection refused: /10.75.43.251:9042)
2015-11-05 14:15:24,847 DEBUG [Reconnection-0] com.datastax.driver.core.Connection - Defuncting connection to /10.75.43.251:9042
com.datastax.driver.core.TransportException: [/10.75.43.251:9042] Cannot connect
        at com.datastax.driver.core.Connection.<init>(Connection.java:104)
        at com.datastax.driver.core.Connection$Factory.open(Connection.java:544)
        at com.datastax.driver.core.Cluster$Manager$5.tryReconnect(Cluster.java:1652)
        at com.datastax.driver.core.AbstractReconnectionHandler.run(AbstractReconnectionHandler.java:124)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
        at java.util.concurrent.FutureTask.run(FutureTask.java:262)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:178)
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:292)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.ConnectException: Connection refused: /10.75.43.251:9042
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.connect(NioClientBoss.java:150)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.processSelectedKeys(NioClientBoss.java:105)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.process(NioClientBoss.java:79)
        at com.datastax.shaded.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:318)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.run(NioClientBoss.java:42)
        at com.datastax.shaded.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
        at com.datastax.shaded.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
        ... 3 more


2015-11-05 14:15:24,847 DEBUG [New I/O worker #8] com.datastax.driver.core.Connection - Connection[/10.75.43.251:9042-24, inFlight=0, closed=true] closing connection
2015-11-05 14:15:24,847 DEBUG [New I/O boss #9] com.datastax.driver.core.Connection - Connection[/10.75.43.251:9042-24, inFlight=0, closed=false] connection error
java.net.ConnectException: Connection refused: /10.75.43.251:9042
        at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
        at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:739)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.connect(NioClientBoss.java:150)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.processSelectedKeys(NioClientBoss.java:105)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.process(NioClientBoss.java:79)
        at com.datastax.shaded.netty.channel.socket.nio.AbstractNioSelector.run(AbstractNioSelector.java:318)
        at com.datastax.shaded.netty.channel.socket.nio.NioClientBoss.run(NioClientBoss.java:42)
        at com.datastax.shaded.netty.util.ThreadRenamingRunnable.run(ThreadRenamingRunnable.java:108)
        at com.datastax.shaded.netty.util.internal.DeadLockProofWorker$1.run(DeadLockProofWorker.java:42)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
        at java.lang.Thread.run(Thread.java:745)
2015-11-05 14:15:24,849 DEBUG [Reconnection-0] com.datastax.driver.core.Cluster - Failed reconnection to /10.75.43.251:9042 ([/10.75.43.251:9042] Cannot connect), scheduling retry in 600000 milliseconds
2015-11-05 14:15:24,849 DEBUG [Cassandra Java Driver worker-44] com.datastax.driver.core.Cluster - Host /10.75.43.251:9042 is DOWN
2015-11-05 14:15:24,849 DEBUG [Cassandra Java Driver worker-44] com.datastax.driver.core.Cluster - Aborting onDown because a reconnection is running on DOWN host /10.75.43.251:9042

我尝试设置 ReconnectionPolicy。这使我可以控制重试延迟。但是重试尝试（说我想要3）仍然不在我的控制之下。

我尝试了 ConstantReconnectPolicy( 它只提供了 reconnectDelay ，它有效。但我也希望控制重试尝试。我正在尝试类似的东西

  private volatile int currentRetryCount;

    class MyReconnectionPolicy implements ReconnectionPolicy {

        @Override
        public ReconnectionSchedule newSchedule() {
            return new MyReconnectionSchedule();

        }
    }

    class MyReconnectionSchedule implements ReconnectionSchedule {

        @Override
        public long nextDelayMs() {
            if (++currentRetryCount < maxReconnectAttempts) {
            return retryIntervalInMilliSec;
            } else {
                // try {
                throw new Error("Exception Occurred. Retry limits exhausted.");
                // } catch (Exception e) {
                // logger.error("Exception Occurred!");
                // return Long.MAX_VALUE;
                // }
            }
        }

    }

这也没有多大帮助。异常不会传播到主程序。因为它不会引发异常。

什么可能是可能的 api（如果暴露）或打开的错误（如果已经有，找不到）。

谢谢！

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2 回答 2

0

我解决了这个问题：

private class CustomExponentialSchedule implements ReconnectionSchedule {

    private int attempts;

    @Override
    public long nextDelayMs() {

        // If totalReconnectionCount is zero, the application won't be never stopped.
        if (totalReconnectionCount != 0 && attempts == totalReconnectionCount) {
            // Kill the Java process.
            System.exit(1);
        }

        if (attempts > maxAttempts) {
            return maxDelayMs;
        }

        return Math.min(baseDelayMs * (1L << attempts++), maxDelayMs);
    }
}
于 2018-02-23T01:30:01.350 回答
0

ReturnsLong.MAX_VALUE将下次重新连接尝试安排在很远的将来，这与取消重新连接基本相同。尽管我会小心，因为您最终可能会失去与所有节点的连接。

于 2015-11-05T13:25:45.400 回答