添加新节点:
hadoop -daemon.sh start datanode
hadoop -daemon.sh start tasktracker
移除一个节点:
hadoop mradmin -refreshnodes
hadoop dfsadmin -refreshnodes

添加新节点:
hadoop -daemon.sh start datanode
hadoop -daemon.sh start tasktracker
移除一个节点:
hadoop mradmin -refreshnodes
hadoop dfsadmin -refreshnodes