1. Namenode FORMAT
[hadoop@localhost ~] $ hdfs namenode -format


2. hadoop 실행
[hadoop@localhost ~] $ start-all.sh


3. 프로세스 확인
[hadoop@localhost ~] jps
10925 SecondaryNameNode
10768 DataNode
11142 NodeManager
11862 Jps
10679 Namenode
11051 ResourceManager