Hadoop - Downgrading from YARN to MRv1 (Cloudera CDH4)

# 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 username

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+'