2.Hadoop_HDFS1.x_伪分布式搭建

环境

• CentOS 6.5
• Apache Hadoop 2.6.5
• JDK 7 (Hadoop3.0以上需要JDK8)
• hadoop-2.6.5.tar.gz

搭建步骤

参考官方文档： https://hadoop.apache.org/docs/r2.6.5/hadoop-project-dist/hadoop-common/SingleCluster.html#Pseudo-Distributed_Operation

1. 安装jdk7

   # 安装
   rpm -i jdk-7u67-linux-x64.rpm 
   whereis java
   # 配置环境变量
   vi + /etc/profile
   # 添加下面代码到profile 末尾
   export JAVA_HOME=/usr/java/jdk1.7.0_67
   PATH=$PATH:$JAVA_HOME/bin
   # 使profile生效
   . /etc/profile
   # 验证是否配置成功
   jps
   

2. 设置ssh免密钥登陆

   Now check that you can ssh to the localhost without a passphrase:

    $ ssh localhost
   

   If you cannot ssh to localhost without a passphrase, execute the following commands:

    $ ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
    $ cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
   

   # 使用ssh本地登录，如果才会有.ssh文件
   ssh localhost
   # 切换到家目录
   cd 
   # 查看是否有.ssh 文件 并进入
   ll -a
   cd ~/.ssh/
   # 生成id dsa 公钥
   ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
   # 把生成的公钥追加到authorized_keys 文件中，完成免密要操作
   cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
   

3. 安装hadoop

   # 创建目录
   mkdir -p /opt/hadoop
   # 解压
   tar xf hadoop-2.6.5.tar.gz -C /opt/hadoop
   

4. 配置hadoop环境变量

   vi + /etc/profile
   # 修改profile 环境变量代码
   export JVAV_HOME=/usr/java/jdk1.7.0_67
   export HADOOP_HOME=/opt/hadoop/hadoop-2.6.5
   PATH=$PATH:$JAVA_HOME/bin:$HADOOP_HOME/bin:$HADOOP_HOME/sbin
   # 使profile生效
   . /etc/profile
   # 测试是否成功
   hdfs
   

5. 修改hadoop路径相关配置文件

   # 修改hadoop-env.sh 中 export JAVA_HOME= 的值为jdk路径
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/hadoop-env.sh
   export JAVA_HOME=/usr/java/jdk1.7.0_67
   
   # 修改 mapred-env.sh 计算框架中 # export JAVA_HOME 的值为jdk路径
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/mapred-env.sh
   export JAVA_HOME=/usr/java/jdk1.7.0_67
   
   # 修改 yarn-env.sh 资源管理框架 # export JAVA_HOME= 的值为jdk路径
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/yarn-env.sh
   export JAVA_HOME=/usr/java/jdk1.7.0_67
   

6. 设置主节点和副本数配置信息

   Pseudo-Distributed Operation

   Hadoop can also be run on a single-node in a pseudo-distributed mode where each Hadoop daemon runs in a separate Java process.

   Configuration

   Use the following:

   etc/hadoop/core-site.xml:

   <configuration>
      <property>
          <name>fs.defaultFS</name>
          <value>hdfs://localhost:9000</value>
      </property>
   </configuration>
   

   etc/hadoop/hdfs-site.xml:

   <configuration>
      <property>
          <name>dfs.replication</name>
          <value>1</value>
      </property> 
   </configuration>
   

   

   dfs.namenode.secondary.http-address	0.0.0.0:50090	The secondary namenode http server address and port.
   dfs.namenode.secondary.https-address	0.0.0.0:50091	The secondary namenode HTTPS server address and port.

   # 设置主节点配置信息 粘入core-site.xml中,修改块文件、元数据信息存放路径
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/core-site.xml
       <property>
           <name>fs.defaultFS</name>
           <value>hdfs://node01:9000</value>
       </property>
       <property>
           <name>hadoop.tmp.dir</name>
           <value>/var/hadoop/pseudo</value>
       </property>
   
   # 设置副本数 粘入hdfs-site.xml,设置 secondaryNode 在hdfs-site.xml 
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/hdfs-site.xml
       <property>
           <name>dfs.replication</name>
           <value>1</value>
       </property>
        <property>
           <name>dfs.namenode.secondary.http-address</name>
           <value>node01:50090</value>
       </property>
   

7. 设置从节点NN

   # 设置从节点 把slaves中localhost 换成从节点主机名
   vi /opt/hadoop/hadoop-2.6.5/etc/hadoop/slaves 
   node01
   

启动

Execution

The following instructions are to run a MapReduce job locally. If you want to execute a job on YARN, see YARN on Single Node.

1. Format the filesystem:

     $ bin/hdfs namenode -format
   

2. Start NameNode daemon and DataNode daemon:

     $ sbin/start-dfs.sh
   

   The hadoop daemon log output is written to the $HADOOP_LOG_DIR directory (defaults to $HADOOP_HOME/logs).

3. Browse the web interface for the NameNode; by default it is available at:

   • NameNode - http://localhost:50070/

4. Make the HDFS directories required to execute MapReduce jobs:

     $ bin/hdfs dfs -mkdir /user
     $ bin/hdfs dfs -mkdir /user/<username>
   

5. Copy the input files into the distributed filesystem:

     $ bin/hdfs dfs -put etc/hadoop input
   

6. Run some of the examples provided:

     $ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.6.5.jar grep input output 'dfs[a-z.]+'
   

7. Examine the output files:

   Copy the output files from the distributed filesystem to the local filesystem and examine them:

     $ bin/hdfs dfs -get output output
     $ cat output/*
   

   or

   View the output files on the distributed filesystem:

     $ bin/hdfs dfs -cat output/*
   

8. When you’re done, stop the daemons with:

     $ sbin/stop-dfs.sh
   

# 格式化namenode 操作
hdfs namenode -format
# 在每次启动格式化后会产生内存镜像文件，命令文件 和clusterID文件
cd /var/hadoop/pseudo/dfs/name/current
# 启动集群
[root@Node001 ~]# /opt/hadoop/hadoop-2.6.5/sbin/start-dfs.sh
Starting namenodes on [node0001]
node0001: starting namenode, logging to /opt/hadoop/hadoop-2.6.5/logs/hadoop-root-namenode-Node001.out
node0001: starting datanode, logging to /opt/hadoop/hadoop-2.6.5/logs/hadoop-root-datanode-Node001.out
Starting secondary namenodes [node0001]
node0001: starting secondarynamenode, logging to /opt/hadoop/hadoop-2.6.5/logs/hadoop-root-secondarynamenode-Nod
e001.out

# 验证是否启动成功 是否有 datenode namenode secondarynamenode
[root@node0001 ~]# jps
1434 SecondaryNameNode
1195 NameNode
1536 Jps
1273 DataNode


# 查看浏览器通讯端口
ss -nal

使用浏览器访问

• 查看端口

  [root@node0001 ~]# ss -nal
  State      Recv-Q Send-Q                        Local Address:Port                          Peer Address:Port 
  LISTEN     0      128                                       *:50070                                    *:*     
  LISTEN     0      128                                      :::22                                      :::*     
  LISTEN     0      128                                       *:22                                       *:*     
  LISTEN     0      100                                     ::1:25                                      :::*     
  LISTEN     0      100                               127.0.0.1:25                                       *:*     
  LISTEN     0      128                                       *:50010                                    *:*     
  LISTEN     0      128                                       *:50075                                    *:*     
  LISTEN     0      128                                       *:50020                                    *:*     
  LISTEN     0      128                           192.168.9.101:9000                                     *:*     
  LISTEN     0      128                           192.168.9.101:50090                                    *:*     
  [root@node0001 ~]# 
  

• 浏览器使用 http://node0001:50070/ 查看网页后台

  

上传文件

# /user/root 为默认目录 可以不写
hdfs dfs -mkdir -p /user/root
# 查看hdfs中创建好的目录
hdfs dfs -ls /
# 创建文件
for i in `seq 100000`;do echo "test hello $i" >> test.txt;done
# 上传文件测试  /user/root 为默认目录 可以不写
hdfs dfs -put test.txt /user/root 

其他

• 关闭hadoop stop-dfs.sh
• 日志文件路径 hadoop-2.6.5/logs
• 块文件存贮路径 /var/hadoop/pseudo/dfs/data/current/BP-1247525349-127.0.0.1-1572210034470/current/finalized/subdir0/subdir0
• 操作记录与内存镜像文件存储地址 /var/hadoop/pseudo/dfs/name/current
• name clusterID 在/var/hadoop/pseudo/dfs/name/current/VERSION 中查看
• data 查看 clusterID /var/hadoop/pseudo/dfs/name/current/VERSION

来源：CSDN

作者：得过且过1223

链接：https://blog.csdn.net/dgqg1223/article/details/104188377