Hadoop - Remove node

@1. Get the IP or Hosts list by running "report" command
$ $HADOOP_HOME/hadoop dfsadmin -report | grep Name

@2. You include IP:Port The following file.
@$HADOOP_HOME/conf/excludes
00.xx.xxx.001:50010

@3. invoke command:
$ $HADOOP_HOME/bin/hadoop dfsadmin -refreshNodes

@4. Verification
$ $HADOOP_HOME/bin/hadoop dfsadmin -report | grep -Eiw ‘Name|Decommission’

@4. This time is MapReduce
@If It has the exclude file, You can command this
$ $HADOOP_HOME/bin/hadoop mradmin -refreshNodes

http://pearlin.info/2012/04/best-way-to-blacklist-node-from-live-hadoop-cluster/