hadoop安装
1 安装java环境
tar -xf jdk-8u131-linux-x64.tar.gz -C /usr/local/
vi /etc/profile
export JAVA_HOME=/usr/local/jdk1.8.0_131
export CLASS_PATH=$JAVA_HOME/bin/lib:$JAVA_HOME/jre/lib:$JAVA_HOME/lib/tool.jar
export PATH=${JAVA_HOME}/bin:$PATH
source /etc/profile
2 ssh互信，免密登录
192.168.1.84 vm1 namenode
192.168.1.85 vm2 datanode
192.168.1.86 vm3 datanode
创建hadoop用户：(namenode和datanode均需要)
useradd hadoop
passwd hadoop
在namenode上生成秘钥：
# su - hadoop
# ssh-keygen
在/home/hadoop/.ssh/目录下生成：id_rsa（私钥）和id_rsa.pub（公钥）
将公钥id_rsa.pub上传至各datanode节点上
在各datanode节点上：（复制namenode上的id_rsa.pub到authorized_keys）
# vi /home/hadoop/.ssh/authorized_keys
文件权限一定是600：
chmod 700 /home/hadoop/.ssh
chmod 600 /home/hadoop/.ssh/authorized_keys
3 安装hadoop
# su - hadoop
# cd /home/hadoop/
下载hadoop包：
https://archive.apache.org/dist/hadoop/common/
https://mirrors.cnnic.cn/apache/hadoop/common/
tar -xf hadoop-3.2.2.tar.gz
cd /home/hadoop/hadoop-3.2.2/etc/hadoop/
修改配置：
vi hadoop-env.sh
export export JAVA_HOME=/usr/local/jdk1.8.0_131
vi core-site.xml
fs.defaultFS
hdfs://192.168.1.84:50070
hadoop.tmp.dir
/home/hadoop/data/tmp
fs.checkpoint.period
3600
vi hdfs-site.xml
dfs.replication
2
dfs.namenode.name.dir
/home/hadoop/data
dfs.datanode.data.dir
/home/hadoop/data
dfs.namenode.secondary.http-address
192.168.1.84:9001
dfs.http.address
0.0.0.0:50070
vi mapred-site.xml
mapred.job.tracker.http.address
0.0.0.0:50030
mapred.task.tracker.http.address
0.0.0.0:50060
mapreduce.framework.name
yarn
mapreduce.application.classpath
/home/hadoop/hadoop-3.2.2/etc/hadoop,
/home/hadoop/hadoop-3.2.2/share/hadoop/common/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/common/lib/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/hdfs/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/hdfs/lib/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/mapreduce/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/mapreduce/lib/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/yarn/*,
/home/hadoop/hadoop-3.2.2/share/hadoop/yarn/lib/*
vi yar-site.xml
yarn.resourcemanager.hostname
vm1
yarn.nodemanager.aux-services
mapreduce_shuffle
vi /home/hadoop/hadoop-3.2.2/etc/hadoop/workers
vm2
vm3