安装
masters：
1台 NameNode
1台 ResourceManager
workers：
剩下的机器既作为 DataNode 也作为 NodeManager
以 Non-Secure Mode 模式安装
需要为 hadoop daemon 配置运维环境和运行参数。
HDFS daemons are NameNode, SecondaryNameNode, and DataNode. YARN daemons are ResourceManager, NodeManager, and WebAppProxy. If MapReduce is to be used, then the MapReduce Job History Server will also be running. For large installations, these are generally running on separate hosts.
配置运行环境
需要配置etc/hadoop/hadoop-env.sh、etc/hadoop/mapred-env.sh、etc/hadoop/yarn-env.sh，还要配置JAVA_HOME
| mon | Environment Variable |
|---|---|
| NameNode | HDFS_NAMENODE_OPTS |
| DataNode | HDFS_DATANODE_OPTS |
| Secondary NameNode | HDFS_SECONDARYNAMENODE_OPTS |
| ResourceManager | YARN_RESOURCEMANAGER_OPTS |
| NodeManager | YARN_NODEMANAGER_OPTS |
| WebAppProxy | YARN_PROXYSERVER_OPTS |
| Map Reduce Job History Server | MAPRED_HISTORYSERVER_OPTS |