Downgrading Apache Hadoop YARN to MapReduce v1

# remove YARN configuration
sudo yum remove hadoop-conf-pseudo


# stop YARN
sudo service hadoop-yarn-resourcemanager stop
sudo service hadoop-yarn-nodemanager stop
sudo service hadoop-mapreduce-historyserver stop


# stop HDFS
sudo for x in `cd /etc/init.d ; ls hadoop-hdfs-*` ; do sudo service $x stop ; done


# Install MRv1
sudo yum install hadoop-0.20-conf-pseudo


# Remove cache dir
sudo rm -rf /var/lib/hadoop-hdfs/cache/


# format namenode
sudo -u hdfs hdfs namenode -format


# start HDFS
sudo for x in `cd /etc/init.d ; ls hadoop-hdfs-*` ; do sudo service $x start ; done


# make /tmp directories and set permissions/ownership
sudo -u hdfs hadoop fs -mkdir /tmp
sudo -u hdfs hadoop fs -chmod -R 1777 /tmp


sudo -u hdfs hadoop fs -mkdir -p /var/lib/hadoop-hdfs/cache/mapred/mapred/staging
sudo -u hdfs hadoop fs -chmod 1777 /var/lib/hadoop-hdfs/cache/mapred/mapred/staging
sudo -u hdfs hadoop fs -chown -R mapred /var/lib/hadoop-hdfs/cache/mapred


sudo -u hdfs mkdir -p /var/lib/hadoop-hdfs/cache/mapred/mapred/local/
sudo chown -R mapred /var/lib/hadoop-hdfs/cache/mapred


# check dir structure
sudo -u hdfs hadoop fs -ls -R /


# start MRv1
for x in `cd /etc/init.d ; ls hadoop-0.20-mapreduce-*` ; do sudo service $x start ; done


# make user directory for your <user>
sudo -u hdfs hadoop fs -mkdir /user/cloudera
sudo -u hdfs hadoop fs -chown cloudera /user/cloudera


# test
hadoop fs -mkdir input
hadoop fs -put /etc/hadoop/conf/*.xml input
hadoop jar /usr/lib/hadoop-0.20-mapreduce/hadoop-examples.jar grep input output 'dfs+'


all should be good on localhost:50030 and 50070