背景：
阅读新闻
CentOS 7.4下Hadoop 3.0单机安装教程
[日期：2018-02-09] 来源：Linux社区 作者：Linux [字体：]
简单记录CentOS 7.4下Hadoop 3.0单机安装教程。
相关下载
hive下载地址
hadoop下载地址
https://mirrors.tuna.tsinghua.edu.cn/apache/hadoop/common/hadoop-3.0.0/hadoop-3.0.0.tar.gz
1. hive安装目录 /opt/hive/apache-hive-2.3.2-bin
2. hadoop安装目录 /opt/hadoop/hadoop-3.0.0
3. JDK安装目录 /usr/java/jdk1.8.0_65
4. 环境变量配置
export JAVA_HOME=/usr/java/jdk1.8.0_65
export HADOOP_HOME=/opt/hadoop/hadoop-3.0.0
export HADOOP_CONF_DIR=${HADOOP_HOME}/etc/hadoop
export HADOOP_COMMON_LIB_NATIVE_DIR=${HADOOP_HOME}/lib/native
export HADOOP_OPTS="-Djava.library.path=${HADOOP_HOME}/lib"
export HIVE_HOME=/opt/hive/apache-hive-2.3.2-bin
export HIVE_CONF_DIR=${HIVE_HOME}/conf
export CLASS_PATH=.:${JAVA_HOME}/lib:${HIVE_HOME}/lib:$CLASS_PATH
export PATH=.:${JAVA_HOME}/bin:${HADOOP_HOME}/bin:${HADOOP_HOME}/sbin:${HIVE_HOME}/bin:$PATH
5. 让环境变量生效
source /etc/profile
6. vim /opt/hadoop/hadoop-3.0.0/etc/hadoop/core-site.xml 修改
<configuration>
<!-- 指定HDFS老大（namenode）的通信地址 -->
<property>
<name>fs.defaultFS</name>
<value>hdfs://localhost:9000</value>
</property>
<!-- 指定hadoop运行时产生文件的存储路径 -->
<property>
<name>hadoop.tmp.dir</name>
<value>/opt/hadoop/tmp</value>
</property>
</configuration>
7. vim /opt/hadoop/hadoop-3.0.0/etc/hadoop/hdfs-site.xml 修改增加以下内容
<configuration>
<property>
<name>dfs.name.dir</name>
<value>/opt/hadoop/hdfs/name</value>
<description>namenode上存储hdfs名字空间元数据 </description>
</property>
<property>
<name>dfs.data.dir</name>
<value>/opt/hadoop/hdfs/data</value>
<description>datanode上数据块的物理存储位置</description>
</property>
<!-- 设置hdfs副本数量 -->
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
</configuration>
8. SSH 设置免密码登录
ssh-keygen -t dsa -P '' -f ~/.ssh/id_dsa
cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys
chmod 0600 ~/.ssh/authorized_keys
9. 启动命令
9.1 初始化
cd /opt/hadoop/hadoop-3.0.0
./bin/hdfs namenode -format
9.2 启动命令
./sbin/start-dfs.sh
9.3 停止命令
./sbin/stop-dfs.sh
错误处理
Starting namenodes on [localhost]
ERROR: Attempting to operate on hdfs namenode as root
ERROR: but there is no HDFS_NAMENODE_USER defined. Aborting operation.
Starting datanodes
ERROR: Attempting to operate on hdfs datanode as root
ERROR: but there is no HDFS_DATANODE_USER defined. Aborting operation.
Starting secondary namenodes [bogon]
ERROR: Attempting to operate on hdfs secondarynamenode as root
ERROR: but there is no HDFS_SECONDARYNAMENODE_USER defined. Aborting operation.
处理1
$ vim sbin/start-dfs.sh
$ vim sbin/stop-dfs.sh
两处增加以下内容
HDFS_DATANODE_USER=root
HADOOP_SECURE_DN_USER=hdfs
HDFS_NAMENODE_USER=root
HDFS_SECONDARYNAMENODE_USER=root
处理2
$ vim sbin/start-yarn.sh
$ vim sbin/stop-yarn.sh
两处增加以下内容
YARN_RESOURCEMANAGER_USER=root
HADOOP_SECURE_DN_USER=yarn
YARN_NODEMANAGER_USER=root
10. 验证安装
:9870/dfshealth.html#tab-overview