java - 错误 sequenceiq/hadoop-docker 写入文件

Question

写入文件时出错

试图将文件写入 sequenceiq/hadoop-docker 我没有。

部署一个docker容器sequenceiq/hadoop-docker，一切就起来了。但是当我尝试写入文件时出现错误

could only be replicated to 0 nodes instead of minReplication (=1). There are 1 datanode(s) running and 1 node(s) are excluded in this operation.

运行

docker run -it --rm --name=hadoopserver -p 8030:8030 -p 8040:8040 -p 8042:8042 -p 8088:8088 -p 19888:19888 -p 49707:49707 -p 50010:50010 -p 50020:50020 -p 50070:50070 -p 50075:50075 -p 50090:50090 -p 9000:9000 sequenceiq/hadoop-docker:latest /etc/bootstrap.sh –d

应用

public static void main(String[] args) throws IOException {
    Configuration conf = new Configuration();
    conf.set("fs.defaultFS", "hdfs://localhost:9000");

    System.setProperty("HADOOP_USER_NAME", "root");
    System.setProperty("hadoop.home.dir", "/");

    FileSystem fileSystem = FileSystem.get(conf);

    try (FSDataOutputStream out = fileSystem.create(new Path("test.txt"), true)) {
        out.write("Test".getBytes());
    }
}

错误

org.apache.hadoop.ipc.RemoteException: File /user/root/test.txt could only be replicated to 0 nodes instead of minReplication (=1).  There are 1 datanode(s) running and 1 node(s) are excluded in this operation.
    at org.apache.hadoop.hdfs.server.blockmanagement.BlockManager.chooseTarget4NewBlock(BlockManager.java:1547)
    at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getNewBlockTargets(FSNamesystem.java:3107)
    at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getAdditionalBlock(FSNamesystem.java:3031)
    at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.addBlock(NameNodeRpcServer.java:724)
    at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.addBlock(ClientNamenodeProtocolServerSideTranslatorPB.java:492)
    at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
    at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:616)
    at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:969)
    at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2049)
    at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2045)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:422)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
    at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2043)

    at org.apache.hadoop.ipc.Client.getRpcResponse(Client.java:1481)
    at org.apache.hadoop.ipc.Client.call(Client.java:1427)
    at org.apache.hadoop.ipc.Client.call(Client.java:1337)
    at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:227)
    at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:116)
    at com.sun.proxy.$Proxy13.addBlock(Unknown Source)
    at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.addBlock(ClientNamenodeProtocolTranslatorPB.java:440)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:398)
    at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeMethod(RetryInvocationHandler.java:163)
    at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invoke(RetryInvocationHandler.java:155)
    at org.apache.hadoop.io.retry.RetryInvocationHandler$Call.invokeOnce(RetryInvocationHandler.java:95)
    at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:335)
    at com.sun.proxy.$Proxy14.addBlock(Unknown Source)
    at org.apache.hadoop.hdfs.DataStreamer.locateFollowingBlock(DataStreamer.java:1733)
    at org.apache.hadoop.hdfs.DataStreamer.nextBlockOutputStream(DataStreamer.java:1536)
    at org.apache.hadoop.hdfs.DataStreamer.run(DataStreamer.java:658)

我做错了什么？

Answer 1

也许这不是您问题的直接答案，而是非常简单和好的hadoop-cluster-docker运行(在 Linux 上)解释以及字数统计示例植入。这让我明白了很多。