Apache Hadoop 3.3.6 – Hadoop: Setting up a Single Node Cluster.

1、解压缩到某个路径

/usr/local/hadoop

2、修改配置文件

/usr/local/hadoop/etc/hadoop/hadoop-env.sh

export JAVA_HOME=/usr/local/javajdk

3、修改配置文件

/usr/local/hadoop/etc/hadoop/core-site.xml

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

/usr/local/hadoop/etc/hadoop/hdfs-site.xml

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

4、测试登录

cd /usr/local/hadoop/etc/hadoop

ssh localhost

5、添加密钥，方便后续登录不用密码

ssh-keygen -t rsa -P '' -f ~/.ssh/id_rsa

cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

chmod 0600 ~/.ssh/authorized_keys

后面登录免密

ssh localhost

6、格式化

cd /usr/local/hadoop/bin

回车运行下方命令

./hdfs namenode -format

7、启动hadoop伪分布式文件系统

cd /usr/local/hadoop/sbin

访问web端

8、创建文件夹

cd /usr/local/hadoop/bin

创建文件夹demo

./hadoop dfs -mkdir /demo

上传文件到demo文件夹

./hadoop dfs -put ./hdfs.cmd /demo

获取上面的文件夹到Linux本地

./hadoop dfs -get /demo/hdfs.cmd /root/

9、配置全局模式，方便任意目录运行命令

vi /etc/profile

添加下列几行

HADOOP_HOME=/usr/local/hadoop
export HADOOP_HOME
PATH=$HADOOP_HOME/bin:$HADOOP_HOME/sbin:$PATH
export PATH

wq保存退出

执行下方命令，使配置生效

source /etc/profile

后面可在任意目录执行

start-dfs.sh

开启hadoop

stop-dfs.sh

关闭hadoop