1、基础环境配置

主机名

IP地址

角色

Hadoop用户

centos05

192.168.48.105

NameNode、ResourceManager、SecondaryNameNode、

DataNode、NodeManager

hadoop

1.1、关闭防火墙和SELinux

1.1.1、关闭防火墙

1.1.2、关闭SELinux

    注:以上操作需要使用root用户

1.2、hosts配置

  

1 | [root@centos05 ~]#  vim/etc/hosts
2 | ##hadoop host####
3 | 192.168.48.105  centos05

 

  

1 | [root@centos05 ~]#  vim /etc/sysconfig//network
2 
3 | HOSTNAME=centos05

  注:以上操作需要使用root用户,通过ping 主机名可以返回对应的IP即可

1.3、创建主机账号及配置无密码访问

  

新建用户,建议用adduser命令

sudo adduser hadoop
passwd hadoop

输入密码后一直按回车即可,最后输入y确定。
在创建hadoop用户的同时也创建了hadoop用户组,下面我们把hadoop用户加入到hadoop用户组
输入
sudo usermod -a -G hadoop hadoop 

前面一个hadoop是组名,后面一个hadoop是用户名。完成后输入一下命令查询结果。
cat  /etc/group

然后再把hadoop用户赋予root权限,让他可以使用sudo命令
切换到可以root的用户输入
sudo gedit /etc/sudoers
sudo vi /etc/sudoers
在图形界面可以用第一个命令,是ubuntu自带的一个文字编辑器,终端命令界面使用第二个命令。有关vi编辑器的使用自行百度。

修改文件如下:
# User privilege specification
root ALL=(ALL) ALL
hadoop ALL=(ALL) ALL
保存退出,hadoop用户就拥有了root权限

 

生成私钥和公钥
ssh-keygen -t rsa
拷贝公钥到主机(需要输入密码)
ssh-copy-id hadoop@hadoop
注:以上操作需要在hadoop用户,通过hadoop用户ssh到本机主机不需要密码即可

 

1.4、Java环境配置

1.4.1、下载JDK

  略

1.4.2、安装java

  略

2、安装hadoop

2.1、下载安装CDH版本的hadoop

2.2、安装配置hadoop

  hadoop的安装配置使用hadoop用户操作;

  • 创建目录,用于存放hadoop数据;
[hadoop@centos05 ~]$ mkdir -p /home/hadoop/app/hadoop/hdfs/{name,data}

 

2.2.1、配置core-site.xml

[hadoop@centos05 ~]$vim  /opt/hadoop/hadoop-2.6.0/etc/hadoop/core-site.xml


<configuration>
    <property>
        <name>fs.defaultFS</name>
        <value>hdfs://localhost:9090</value>
    </property>
    <property>
        <name>hadoop.tmp.dir</name>
        <value>file:/opt/hadoop/tmp</value>
    </property>
</configuration>

 

2.2.2、配置hdfs-site.xml

[hadoop@centos05 hadoop]$ vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/hdfs-site.xml

<configuration>
    <property>
        <name>dfs.replication</name>
        <value>1</value>
    </property>
    <property>
        <name>dfs.namenode.name.dir</name>
        <value>/opt/hadoop/hdfs/name</value>
    </property>
    <property>
        <name>dfs.datanode.data.dir</name>
        <value>/opt/hadoop/hdfs/data</value>
    </property>
    <property>
        <name>dfs.webhdfs.enabled</name>
        <value>true</value>
    </property>
</configuration>

 

2.2.3、配置mapred-site.xml

[hadoop@centos05 hadoop]$cd /opt/hadoop/hadoop-2.6.0/etc/hadoop

[hadoop@centos05 hadoop]$cp mapred-site.xml.template mapred-site.xml

[hadoop@centos05 hadoop]$vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/mapred-site.xml

<configuration>
    <property>
        <name>mapreduce.framework.name</name>
        <value>yarn</value>
    </property>
</configuration>

 

2.2.4、配置yarn-site.xml

[hadoop@centos05 hadoop]$  vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/yarn-site.xml

<configuration>
<!-- Site specific YARN configuration properties -->
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>
</configuration>

 

2.2.5、配置slaves

[hadoop@centos05 hadoop]$ vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/slaves

centos05

 

2.2.6、配置hadoop-env

  修改hadoop-env.sh文件的JAVA_HOME环境变量,操作如下:  

[hadoop@centos05 hadoop]$ vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/hadoop-env.sh

export JAVA_HOME=/opt/java/jdk1.8.0_191

 

2.2.7、配置yarn-env

  修改yarn-env.sh文件的JAVA_HOME环境变量,操作如下:

[hadoop@centos05 hadoop]$ vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/hadoop-env.sh

export JAVA_HOME=/opt/java/jdk1.8.0_191

 

2.2.8、配置mapred-env

  修改mapred-env.sh文件的JAVA_HOME环境变量,操作如下:

[hadoop@centos05 hadoop]$ vim /opt/hadoop/hadoop-2.6.0/etc/hadoop/hadoop-env.sh

export JAVA_HOME=/opt/java/jdk1.8.0_191

 

2.2.9、配置HADOOP_PREFIX

  配置HADOOP主机用户环境变量:

[hadoop@centos05 ~]$ vim .bash_profile

####HADOOP_PREFIX####
export HADOOP_PREFIX=/opt/hadoop/hadoop-2.6.0
export PATH=$PATH:$HADOOP_PREFIX/bin:$HADOOP_PREFIX/sbin

  启用环境变量

[hadoop@centos05 ~]$ source .bash_profile

  注:通过echo $HADOOP_PREFIX命令返回hadoop的安装目录

3、启动hadoop伪分布式

3.1、启动hdfs和yarn

  • 格式化hdfs
[hadoop@centos05 ~]$  hdfs namenode -format
  • 启动dfs
  • 启动yarn
[hadoop@centos05 ~]$  start-dfs.sh

[hadoop@centos05 ~]$  start-yarn.sh
  • 查看启动的进程
[hadoop@centos05 ~]$ jps
18265 DataNode
18615 ResourceManager
18463 SecondaryNameNode
31343 Jps
18728 NodeManager
18152 NameNode

注:关闭dfs命令为:stop-dfs.sh     stop-yarn.sh

3.3、启动集群

  hdfs和yarn的启动可以使用一条命令执行:  

启动:start-all.sh
关闭:  stop-all.sh

 

  • 启动后的所有进程:  
[hadoop@centos05 ~]$ start-all.sh
This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
Starting namenodes on [centos05]
centos05: starting namenode, logging to /opt/hadoop/hadoop-2.6.0/logs/hadoop-hadoop-namenode-centos05.out
centos05: starting datanode, logging to /opt/hadoop/hadoop-2.6.0/logs/hadoop-hadoop-datanode-centos05.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to 
      /opt/hadoop/hadoop-2.6.0/logs/hadoop-hadoop-secondarynamenode-centos05.out
starting yarn daemons
starting resourcemanager, logging to /opt/hadoop/hadoop-2.6.0/logs/yarn-hadoop-resourcemanager-centos05.out
centos05: starting nodemanager, logging to /opt/hadoop/hadoop-2.6.0/logs/yarn-hadoop-nodemanager-centos05.out
[hadoop@centos05 ~]$

 

  • 启动后的所有进程:
[hadoop@centos05 ~]$ jps
32640 NodeManager
529 Jps
32057 NameNode
32526 ResourceManager
32356 SecondaryNameNode
32172 DataNode

 

4、hdfs的shell操作和Wordcount演示

4.1、简单的hdfs shell操作

  • 创建目录
[hadoop@centos05 ~]$ hadoop fs -mkdir /input_test
$ hadoop fs -mkdir /output_test
  • 查看目录
[hadoop@centos05 ~]$ hadoop fs -ls /
Found 3 items
drwxr-xr-x   - hadoop supergroup          0 2018-11-27 23:04 /input_test
drwxr-xr-x   - hadoop supergroup          0 2018-11-27 23:27 /output_test
drwx------   - hadoop supergroup          0 2018-11-27 23:08 /tmp
  • 上传文件
[hadoop@centos05 /]$ hadoop fs -put  /opt/hadoop/hadoop-2.6.0/share/doc/index.html  /input_test
  • 查看上传文件
[hadoop@centos05 /]$ hadoop fs -ls    /input_test/index.html
-rw-r--r--   1 hadoop supergroup      19968 2018-11-28 10:08 /input_test/index.html
  • 查看文本文件内容
[hadoop@centos05 /]$ hadoop fs -cat    /input_test/index.html

4.2、Wordcount

  将HDFS上/input_text/index.html 使用hadoop内置Wordcount的jar包统计文档的Wordcount

  • 启动测试
[hadoop@centos05 /]$ hadoop jar /opt/hadoop/hadoop-2.6.0/share/hadoop/mapreduce/
                     hadoop-mapreduce-examples-2.6.0-cdh5.15.1.jar wordcount 
                    /input_test/index.html /output_test/runcount
18/11/28 10:18:53 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
18/11/28 10:18:54 INFO input.FileInputFormat: Total input paths to process : 1
18/11/28 10:18:54 INFO mapreduce.JobSubmitter: number of splits:1
18/11/28 10:18:55 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1543369969234_0002
18/11/28 10:18:56 INFO impl.YarnClientImpl: Submitted application application_1543369969234_0002
18/11/28 10:18:56 INFO mapreduce.Job: The url to track the job: 
                                      http://centos05:8088/proxy/application_1543369969234_0002/
18/11/28 10:18:56 INFO mapreduce.Job: Running job: job_1543369969234_0002
18/11/28 10:19:16 INFO mapreduce.Job: Job job_1543369969234_0002 running in uber mode : false
18/11/28 10:19:16 INFO mapreduce.Job:  map 0% reduce 0%
18/11/28 10:19:31 INFO mapreduce.Job:  map 100% reduce 0%
18/11/28 10:19:43 INFO mapreduce.Job:  map 100% reduce 100%
18/11/28 10:19:44 INFO mapreduce.Job: Job job_1543369969234_0002 completed successfully
18/11/28 10:19:45 INFO mapreduce.Job: Counters: 49
        File System Counters
                FILE: Number of bytes read=13728
                FILE: Number of bytes written=313427
                FILE: Number of read operations=0
                FILE: Number of large read operations=0
                FILE: Number of write operations=0
                HDFS: Number of bytes read=20075
                HDFS: Number of bytes written=11719
                HDFS: Number of read operations=6
                HDFS: Number of large read operations=0
                HDFS: Number of write operations=2
        Job Counters 
                Launched map tasks=1
                Launched reduce tasks=1
                Data-local map tasks=1
                Total time spent by all maps in occupied slots (ms)=12498
                Total time spent by all reduces in occupied slots (ms)=9428
                Total time spent by all map tasks (ms)=12498
                Total time spent by all reduce tasks (ms)=9428
                Total vcore-milliseconds taken by all map tasks=12498
                Total vcore-milliseconds taken by all reduce tasks=9428
                Total megabyte-milliseconds taken by all map tasks=12797952
                Total megabyte-milliseconds taken by all reduce tasks=9654272
        Map-Reduce Framework
                Map input records=383
                Map output records=1087
                Map output bytes=18860
                Map output materialized bytes=13728
                Input split bytes=107
                Combine input records=1087
                Combine output records=504
                Reduce input groups=504
                Reduce shuffle bytes=13728
                Reduce input records=504
                Reduce output records=504
                Spilled Records=1008
                Shuffled Maps =1
                Failed Shuffles=0
                Merged Map outputs=1
                GC time elapsed (ms)=174
                CPU time spent (ms)=0
                Physical memory (bytes) snapshot=0
                Virtual memory (bytes) snapshot=5455101952
                Total committed heap usage (bytes)=165810176
        Shuffle Errors
                BAD_ID=0
                CONNECTION=0
                IO_ERROR=0
                WRONG_LENGTH=0
                WRONG_MAP=0
                WRONG_REDUCE=0
        File Input Format Counters 
                Bytes Read=19968
        File Output Format Counters 
                Bytes Written=11719
[hadoop@centos05 /]$
  • 查看结果
[hadoop@centos05 /]$ hadoop fs -ls /output_test/runcount/

Found 2 items
-rw-r--r--   1 hadoop supergroup          0 2018-11-28 10:19 /output_test/runcount/_SUCCESS
-rw-r--r--   1 hadoop supergroup      11719 2018-11-28 10:19 /output_test/runcount/part-r-00000

[hadoop@centos05 /]$ hadoop fs -cat  /output_test/runcount/part-r-00000
2018-08-09      2
<!--    2
<!DOCTYPE       1
</a>    3
</body> 1
</div>  13
</head> 1
</html> 1
</li>   84
</style>        1
</ul>   12
<a      94
<body   1
<div    15
......略

5、遇到的问题

5.1、WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable

解决:导致该问题的改版本是因为${HADOOP_PREFIX}/lib/native目录没有lib库,解决办法是到hadoop官网下载2.6的包,把lib/native目录下的数据拷贝过去。

5.2、openssl: false Cannot load libcrypto.so (libcrypto.so: 无法打开共享对象文件: 没有那个文件或目录)!

解决:/usr/lib64/目录下做一个libcrypto.so软连

cd /usr/lib64/
ln -s /usr/lib64/libcrypto.so.1.0.1e libcrypto.so
  • 使用命令export HADOOP_ROOT_LOGGER=DEBUG,console可以在终端上看到更详细的日志信息方便排查问题;
  • 以上两个问题可以使用命令检查是否为true:hadoop checknative

注:${HADOOP_PREFIX}表示hadoop的安装目录,或者说是${HADOOP_HOME}

6、参考资料

http://archive.cloudera.com/cdh5/cdh/5/hadoop-2.6.0-cdh5.7.5/hadoop-project-dist/hadoop-common/SingleCluster.html