Atittit HDFS hadoop 大数据文件系统java使用总结 目录 1. 操作系统，进行操作 1 2. Hdfs 类似nfs ftp远程分布式文件服务 2 3. 启动hdfs服务start

Atittit HDFS hadoop 大数据文件系统java使用总结

 

目录

1. 操作系统，进行操作 1

2. Hdfs 类似nfs ftp远程分布式文件服务 2

3. 启动hdfs服务start-dfs.cmd 2

3.1. 配置core-site.xml 2

3.2. 启动 2

3.3. Code 2

4. prob总结 6

4.1. 启动hdfs服务中提示windows找不到hadoop 6

4.2. D:\haddop\hadoop-3.1.1\bin\hdfs namenode -format 6

4.3. 提示file://没权限 10

4.4. 347java.io.IOException: NameNode is not formatted 11

4.5. org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory C:\tmp\hadoop-Administrator\dfs\name is in an inconsistent state: storage directory does not exist or is not accessible. 11

4.6. Unsafe link  ,, 12

4.7. Unkonw host  java.net.ConnectException: Connection refused: no further information 12

5. Theory 12

5.1. 建立文件夹 13

5.2. 写文件 13

6. ref 13

 

 

文件系统的几种操作

 

  1. 操作系统，进行操作
  1. 文件夹的操作：增删改查
  2. 远程文件的IO操作
  3. 文件的上传下载 （本地 远程文件复制操作

 

.具体的操作命令

  1. 根据配置获取HDFS文件操作系统（共有三种方式）
    1. 方法一：直接获取配置文件方法
      通常情况下该方法用于本地有hadoop系统，可以直接进行访问。此时仅需在配置文件中指定要操作的文件系统为hdfs即可。这里的conf的配置文件可以设置hdfs的各种参数，并且优先级比配置文件要搞
    2. 方法二：指定URI路径，进而获取配置文件创建操作系统
      通常该方法用于本地没有hadoop系统，但是可以通过URI的方式进行访问。此时要给给定hadoop的NN节点的访问路径，hadoop的用户名，以及配置文件信息（此时会自动访问远程hadoop的配置文件）
  1. Hdfs 类似nfs ftp远程分布式文件服务
  2. 启动hdfs服务start-dfs.cmd
    1. 配置core-site.xml

 

D:\haddop\hadoop-3.1.1\etc\hadoop>core-site.xml

 

<configuration>

 

 <property>

  <name>fs.default.name</name>

  <value>hdfs://huabingood01:9000</value>

</property>

 

</configuration>

 

    1. 启动

 

    1. Code

package hdfsHadoopUse;

 

import java.io.IOException;

 

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.fs.FileSystem;

import org.apache.hadoop.fs.Path;

 

public class hdfsHadoopClass {

 

public static void main(String[] args) throws IOException {

 String pathToCreate = "/firstDirS09/secdirS09";

 hdfsHadoopClass hdfsHadoopClass = new hdfsHadoopClass();

FileSystem fs=hdfsHadoopClass.getHadoopFileSystem();

hdfsHadoopClass.myCreatePath(fs, pathToCreate);

System.out.println("--f");

}

/**

     * 根据配置文件获取HDFS操作对象

     * 有两种方法：

     *  1.使用conf直接从本地获取配置文件创建HDFS对象

     *  2.多用于本地没有hadoop系统，但是可以远程访问。使用给定的URI和用户名，访问远程的配置文件，然后创建HDFS对象。

     * @return FileSystem

 * @throws IOException

     */

    public FileSystem getHadoopFileSystem() throws IOException {

 

 

        FileSystem fs = null;

        Configuration conf = null;

 

        // 方法一，本地有配置文件，直接获取配置文件（core-site.xml，hdfs-site.xml）

        // 根据配置文件创建HDFS对象

        // 此时必须指定hdsf的访问路径。

        conf = new Configuration();

        // 文件系统为必须设置的内容。其他配置参数可以自行设置，且优先级最高

        conf.set("fs.defaultFS", "hdfs://0.0.0.0:19000");

        conf.set("fs.hdfs.impl",org.apache.hadoop.hdfs.DistributedFileSystem.class.getName());  

        

            // 根据配置文件创建HDFS对象

            fs = FileSystem.get(conf);

       

 

 

        return fs;

    }

    

    /**

     * 这里的创建文件夹同shell中的mkdir -p 语序前面的文件夹不存在

     * 跟java中的IO操作一样，也只能对path对象做操作；但是这里的Path对象是hdfs中的

     * @param fs

     * @return

     * @throws IOException

     */

    public boolean myCreatePath(FileSystem fs, String pathToCreate) throws IOException{

        boolean b = false;

 

     //   String pathToCreate = "/hyw/test/huabingood/hyw";

Path path = new Path(pathToCreate);

        try {

            // even the path exist,it can also create the path.

            b = fs.mkdirs(path);

        }   finally {

           

                fs.close();

           

        }

        return b;

    }

}

 

  1. prob总结

 

Exception in thread "main" java.lang.IllegalArgumentException: java.net.UnknownHostException: huabingood01

Exception in thread "main" java.lang.IllegalArgumentException: java.net.UnknownHostException: huabingood01

需要启动hdfs服务。。

%HADOOP_PREFIX%\sbin\start-dfs.cmd

    1. 启动hdfs服务中提示windows找不到hadoop

start-dfs.cmd

start "Apache Hadoop Distribution" hadoop namenode

start "Apache Hadoop Distribution" hadoop datanode

需要先建立namenode

 D:\haddop\hadoop-3.1.1\bin\hdfs namenode -format

这里的hadoop指的是应该是bin\hadoop.cmd命令，把他加入到path目录envi pathvar

    1. D:\haddop\hadoop-3.1.1\bin\hdfs namenode -format

D:\haddop\hadoop-3.1.1\sbin> D:\haddop\hadoop-3.1.1\bin\hdfs namenode -format

2018-10-28 07:02:54,801 INFO namenode.NameNode: STARTUP_MSG:

/************************************************************

STARTUP_MSG: Starting NameNode

STARTUP_MSG:   host = hmNotePC/192.168.1.101

STARTUP_MSG:   args = [-format]

STARTUP_MSG:   version = 3.1.1

STARTUP_MSG:   classpath = D:\haddop\hadoop-3.1.1\etc\hadoop;D:\haddop\hadoop-3.1.1\share\had

STARTUP_MSG:   build = https://github.com/apache/hadoop -r 2b9a8c1d3a2caf1e733d57f346af3ff0d5ba529c; compiled by 'leftnoteasy' on 2018-08-02T04:26Z

STARTUP_MSG:   java = 1.8.0_31

************************************************************/

2018-10-28 07:02:54,854 INFO namenode.NameNode: createNameNode [-format]

Formatting using clusterid: CID-ecf4351a-e57c-411b-8ef3-2198981bc44b

2018-10-28 07:02:56,060 INFO namenode.FSEditLog: Edit logging is async:true

2018-10-28 07:02:56,090 INFO namenode.FSNamesystem: KeyProvider: null

2018-10-28 07:02:56,092 INFO namenode.FSNamesystem: fsLock is fair: true

2018-10-28 07:02:56,100 INFO namenode.FSNamesystem: Detailed lock hold time metrics enabled: false

2018-10-28 07:02:56,119 INFO namenode.FSNamesystem: fsOwner             = Administrator (auth:SIMPLE)

2018-10-28 07:02:56,120 INFO namenode.FSNamesystem: supergroup          = supergroup

2018-10-28 07:02:56,120 INFO namenode.FSNamesystem: isPermissionEnabled = true

2018-10-28 07:02:56,121 INFO namenode.FSNamesystem: HA Enabled: false

2018-10-28 07:02:56,203 INFO common.Util: dfs.datanode.fileio.profiling.sampling.percentage set to 0. Disabling file IO profiling

2018-10-28 07:02:56,229 INFO blockmanagement.DatanodeManager: dfs.block.invalidate.limit: configured=1000, counted=60, effected=1000

2018-10-28 07:02:56,229 INFO blockmanagement.DatanodeManager: dfs.namenode.datanode.registration.ip-hostname-check=true

2018-10-28 07:02:56,238 INFO blockmanagement.BlockManager: dfs.namenode.startup.delay.block.deletion.sec is set to 000:00:00:00.000

2018-10-28 07:02:56,239 INFO blockmanagement.BlockManager: The block deletion will start around 2018 十月 28 07:02:56

2018-10-28 07:02:56,243 INFO util.GSet: Computing capacity for map BlocksMap

2018-10-28 07:02:56,243 INFO util.GSet: VM type       = 64-bit

2018-10-28 07:02:56,248 INFO util.GSet: 2.0% max memory 889 MB = 17.8 MB

2018-10-28 07:02:56,251 INFO util.GSet: capacity      = 2^21 = 2097152 entries

2018-10-28 07:02:56,269 INFO blockmanagement.BlockManager: dfs.block.access.token.enable = false

2018-10-28 07:02:56,362 INFO Configuration.deprecation: No unit for dfs.namenode.safemode.extension(30000) assuming MILLISECONDS

2018-10-28 07:02:56,362 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.threshold-pct = 0.9990000128746033

2018-10-28 07:02:56,363 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.min.datanodes = 0

2018-10-28 07:02:56,364 INFO blockmanagement.BlockManagerSafeMode: dfs.namenode.safemode.extension = 30000

2018-10-28 07:02:56,364 INFO blockmanagement.BlockManager: defaultReplication         = 3

2018-10-28 07:02:56,365 INFO blockmanagement.BlockManager: maxReplication             = 512

2018-10-28 07:02:56,366 INFO blockmanagement.BlockManager: minReplication             = 1

2018-10-28 07:02:56,366 INFO blockmanagement.BlockManager: maxReplicationStreams      = 2

2018-10-28 07:02:56,367 INFO blockmanagement.BlockManager: redundancyRecheckInterval  = 3000ms

2018-10-28 07:02:56,368 INFO blockmanagement.BlockManager: encryptDataTransfer        = false

2018-10-28 07:02:56,368 INFO blockmanagement.BlockManager: maxNumBlocksToLog          = 1000

2018-10-28 07:02:56,425 INFO util.GSet: Computing capacity for map INodeMap

2018-10-28 07:02:56,426 INFO util.GSet: VM type       = 64-bit

2018-10-28 07:02:56,426 INFO util.GSet: 1.0% max memory 889 MB = 8.9 MB

2018-10-28 07:02:56,427 INFO util.GSet: capacity      = 2^20 = 1048576 entries

2018-10-28 07:02:56,428 INFO namenode.FSDirectory: ACLs enabled? false

2018-10-28 07:02:56,429 INFO namenode.FSDirectory: POSIX ACL inheritance enabled? true

2018-10-28 07:02:56,429 INFO namenode.FSDirectory: XAttrs enabled? true

2018-10-28 07:02:56,430 INFO namenode.NameNode: Caching file names occurring more than 10 times

2018-10-28 07:02:56,440 INFO snapshot.SnapshotManager: Loaded config captureOpenFiles: false, skipCaptureAccessTimeOnlyChange: false, snapshotDiffAllowSnapRo

 

2018-10-28 07:02:56,444 INFO snapshot.SnapshotManager: SkipList is disabled

2018-10-28 07:02:56,452 INFO util.GSet: Computing capacity for map cachedBlocks

2018-10-28 07:02:56,452 INFO util.GSet: VM type       = 64-bit

2018-10-28 07:02:56,453 INFO util.GSet: 0.25% max memory 889 MB = 2.2 MB

2018-10-28 07:02:56,453 INFO util.GSet: capacity      = 2^18 = 262144 entries

2018-10-28 07:02:56,467 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.window.num.buckets = 10

2018-10-28 07:02:56,468 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.num.users = 10

2018-10-28 07:02:56,469 INFO metrics.TopMetrics: NNTop conf: dfs.namenode.top.windows.minutes = 1,5,25

2018-10-28 07:02:56,475 INFO namenode.FSNamesystem: Retry cache on namenode is enabled

2018-10-28 07:02:56,476 INFO namenode.FSNamesystem: Retry cache will use 0.03 of total heap and retry cache entry expiry time is 600000 millis

2018-10-28 07:02:56,481 INFO util.GSet: Computing capacity for map NameNodeRetryCache

2018-10-28 07:02:56,482 INFO util.GSet: VM type       = 64-bit

2018-10-28 07:02:56,482 INFO util.GSet: 0.029999999329447746% max memory 889 MB = 273.1 KB

2018-10-28 07:02:56,483 INFO util.GSet: capacity      = 2^15 = 32768 entries

2018-10-28 07:02:56,527 INFO namenode.FSImage: Allocated new BlockPoolId: BP-1079199093-192.168.1.101-1540681376517

2018-10-28 07:02:56,547 INFO common.Storage: Storage directory \tmp\hadoop-Administrator\dfs\name has been successfully formatted.

2018-10-28 07:02:56,580 INFO namenode.FSImageFormatProtobuf: Saving image file \tmp\hadoop-Administrator\dfs\name\current\fsimage.ckpt_0000000000000000000 us

2018-10-28 07:02:56,717 INFO namenode.FSImageFormatProtobuf: Image file \tmp\hadoop-Administrator\dfs\name\current\fsimage.ckpt_0000000000000000000 of size 3

2018-10-28 07:02:56,741 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0

2018-10-28 07:02:56,756 INFO namenode.NameNode: SHUTDOWN_MSG:

/************************************************************

SHUTDOWN_MSG: Shutting down NameNode at hmNotePC/192.168.1.101

************************************************************/

    1. 提示file://没权限

D:\haddop\hadoop-3.1.1\etc\hadoop>core-site.xml

 

<configuration>

 

 <property>

  <name>fs.default.name</name>

  <value>hdfs://huabingood01:9000</value>

</property>

 

</configuration>

 

    1. 347java.io.IOException: NameNode is not formatted

 

评论

 

访问localhost:50070失败，说明namenode启动失败
3、查看namenode启动日志

 

    1. org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory C:\tmp\hadoop-Administrator\dfs\name is in an inconsistent state: storage directory does not exist or is not accessible.

        at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverStorageDirs(FSI

mage.java:376)

        at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(

 

    1. Unsafe link  ,,

Hadoop.dll  winutil.exe  feodg   system  win  dir hto...maybe  need boot

    1. Unkonw host  java.net.ConnectException: Connection refused: no further information

 

D:\haddop\hadoop-3.1.1\etc\hadoop>core-site.xml

 

<configuration>

 

 <property>

  <name>fs.default.name</name>

  <value>hdfs://huabingood01:9000</value>

</property>

 

</configuration>

    conf = new Configuration();

        // 文件系统为必须设置的内容。其他配置参数可以自行设置，且优先级最高

        conf.set("fs.defaultFS", "hdfs://0.0.0.0:19000");

        conf.set("fs.hdfs.impl",org.apache.hadoop.hdfs.DistributedFileSystem.class.getName());  

        

 

Cfg file and code url yao yyo..

 

 

  1. Theory

 

C:\tmp\hadoop-Administrator>tree

卷 p1sys 的文件夹 PATH 列表

卷序列号为 A87E-7AB4

C:.

├─dfs

│  ├─data

│  └─name

└─nm-local-dir

 

    1. 建立文件夹

 

 String pathToCreate = "/firstDirS09/secdirS09";

    hdfsHadoopClass.myCreatePath(fs, pathToCreate);

实际建立的文件夹在的盘

 

D:\firstDirS09\secdirS09

 

    1. 写文件

 

    //wirte file

FSDataOutputStream FSDataOutputStream1 = fs.create(new Path("/file1S09.txt"));  

FSDataOutputStream1.writeUTF("attilax bazai");

FSDataOutputStream1.close();

 

 

D:\file1S09.txt

D:\.file1S09.txt.crc

 

  1. ref

使用javaAPI操作hdfs - huabingood - 博客园.html

 

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原文地址：https://www.cnblogs.com/attilax/p/15197507.html