1. Basic configuration
1. Server distribution and server name
192.168.1.1 primary name node master
192.168.1.2 data node 1
slave1 192.168.1.3 data node 2 slave2
The command to temporarily change the hostname is (root privileges):
hostname <newname>
A permanent change requires modification of the configuration file /etc/sysconfig/network.
HOSTNAME=master
2, hosts file settings
In the "/etc/hosts" file of each server, add the following:
192.168.1.1 master
192.168.1.2 slave1
192.168.1.3 slave2
3. SSH password-free login
Between the master and all the slaves, two-way SSH password-free access needs to be implemented (there is no need to implement between the slave and the slave. In order to simplify the steps, SSH password-free login between the slave and the slave is also implemented here).
3.1 Basic Services
Two services are required: ssh and rsync, the query method:
rpm –qa | grep openssh
rpm –qa | grep rsync
3.2 Generate public key and private key
Execute the command: ssh-keygen –t rsa –P ''
This command generates its passwordless key pair, and when asked for the save path, press Enter to use the default path. The generated key pair: id_rsa and id_rsa.pub, which are stored in the "~/.ssh" directory by default, including two files, id_rsa and id_rsa.pub, which are the private key and the public key, respectively.
3.3 Write the trust file
Run the following command to write the public key to the trust file:
cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
然后修改authorized_keys文件的权限：
chmod 600 ~/.ssh/authorized_keys
3.4 配置sshd服务
用root用户登录服务器修改SSH配置文件"/etc/ssh/sshd_config"的下列内容：
RSAAuthentication yes # 启用 RSA 认证
PubkeyAuthentication yes # 启用公钥私钥配对认证方式
AuthorizedKeysFile .ssh/authorized_keys # 公钥文件路径（和上面生成的文件同）
设置完之后记得重启SSH服务，才能使刚才设置有效：
service sshd restart
3.5 归档信任文件
将所有authorized_keys文件内容组合成一份authorized_keys文件，然后替换每台服务器上原有的authorized_keys文件。
验证配置是否成功，使用普通用户，执行如下命令：
ssh <hostname>
如果执行成功，则说明配置成功。
二、Hadoop编译安装
1、jdk下载安装
tar -xvzf jdk-8u121-linux-x64.gz -C /usr/local
cd /usr/local
vi /etc/profile
添加：
export JAVA_HOME=/usr/local/jdk1.8.0_121
export CLASS_PATH=$JAVA_HOME/lib:$JAVA_HOME/jre/lib
export PATH=$PATH:$JAVA_HOME/bin
2、hadoop下载安装
tar -xvzf hadoop-2.7.3.tar.gz -C /usr/local
cd /usr/local
mv hadoop-2.7.3 hadoop
(重命名为hadoop）
cd hadoop
mkdir tmp
vi /etc/profile
添加：
export HADOOP_HOME=/usr/local/hadoop
export PATH=$PATH:$HADOOP_HOME/bin
2.1 配置hadoop-env.sh
文件在/usr/local/hadoop/etc/hadoop目录下
vi hadoop-env.sh
添加：
export JAVA_HOME=/usr/local/jdk1.8.0_121
export CLASS_PATH=$JAVA_HOME/lib:$JAVA_HOME/jre/lib
2.2 配置core-site.xml文件
文件在/usr/local/hadoop/etc/hadoop目录下，修改Hadoop核心配置文件core-site.xml，这里配置的是HDFS的地址和端口号。
vi /usr/local/hadoop/etc/hadoop/core-site.xml
<configuration>
<property>
<name>hadoop.tmp.dir</name>
<value>/usr/local/hadoop/tmp</value>
</property>
<property>
<name>fs.defaultFS</name>
<value>hdfs://master:8082</value>
</property>
</configuration>
2.3 配置hdfs-site.xml文件
文件在/usr/local/hadoop/etc/hadoop目录下，修改Hadoop中HDFS的配置，配置的备份方式默认为3。
<configuration>
<property>
<name>dfs.replication</name>
<value>2</value>
</property>
<property>
<name>dfs.namenode.name.dir</name>
<value>file:/usr/local/hadoop/tmp/dfs/name</value>
</property>
<property>
<name>dfs.datanode.data.dir</name>
<value>file:/usr/local/hadoop/tmp/dfs/data</value>
</property>
</configuration>
2.4 配置mapred-env.xml文件
export JAVA_HOME=/usr/local/jdk1.8.0_121
2.5 配置mapred-site.xml文件
修改Hadoop中MapReduce的配置文件，配置的是JobTracker的地址和端口。
cp mapred-site.xml.template mapred-site.xml
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>http://master:9001</value>
</property>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
</configuration>
2.6 配置yarn-env.xml文件
export JAVA_HOME=/usr/local/jdk1.8.0_121
2.7 配置yarn-site.xml文件
<configuration>
<!-- Site specific YARN configuration properties -->
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
<property>
<name>yarn.resourcemanager.webapp.address</name>
<value>master:8088</value>
</property>
<property>
<name>yarn.log-aggregation-enable</name>
<value>true</value>
</property>
<property>
<name>yarn.log-aggregation.retain-seconds</name>
<value>640800</value>
</property>
</configuration>
2.8配置slaves，添加
master
slave1
slave2
2.9 将配置好的hadoop文件拷到各个服务器相应目录
2.10 执行hadoop
所有节点需要关闭防火墙：
/bin/systemctl stop firewalld
（启用防火墙命令是：systemctl mask firewalld）
在主节点上执行，启动集群
cd /usr/local/hadoop
（切换至hadoop目录）
hdfs namenode -format
（格式化hdfs）
sbin/start-dfs.sh
（启动hdfs）
检查进程是否正常启动：jps
hdfs信息查看：
hdfs dfsadmin -report
或hdfs fsck / -files -blocks
集群的后续维护（关闭/启动所有）：
sbin/start-all.sh
sbin/stop-all.sh
（关闭防火墙才能访问）