== Hadoop ==


|| '''Server''' || '''OS''' || '''Memory [GB]''' || '''CPU Type''' || '''Arch''' || '''CPU Speed''' || '''CPUs''' || '''Cores''' || '''Threads''' || '''Local Storage [TB]''' || '''Login''' || '''Description''' ||
|| ilhadoop     || CentOS 6.6  || 64          || Opteron 6276 || 64 bit || 2.3       || 2    || 32   || 32     || 2                  || CS      || !JobTracker, !NameNode ||
|| ilh01-ilh40  || CentOS 6.9  || 64          || Opteron 6320 || 64 bit || 2.8       || 1    || 8    || 8      || 8                  || N/A     || !TaskTracker, !DataNode ||

Before updating notes:

=== Java version ===
{{{
adrijan@ilh02:~$ java -version
java version "1.8.0_45"
Java(TM) SE Runtime Environment (build 1.8.0_45-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.45-b02, mixed mode)
}}}

Download: http://www.oracle.com/technetwork/java/javase/downloads/java-archive-javase8-2177648.html

File attached (registration needed to download older versions of java) [[attachment:jre-8u45-linux-x64.tar.gz]]

Ubuntu 16.04.3:
 * update-alternatives --install /usr/bin/java java /opt/java/jre1.8.0_45/bin/java 1
 * update-alternatives --set java /opt/java/jre1.8.0_45/bin/java

What to take from old machines:
 * UID and GID of hdfs
 * fstab
 * hadoop configuration files

{{{
#START DATANODE
sudo -H -u hdfs bash -c 'export JAVA_HOME=/opt/java; cd /opt/hadoop-2.6.0-cdh5.4.2 ; /opt/hadoop-2.6.0-cdh5.4.2/sbin/hadoop-daemon.sh --config /opt/hadoop-2.6.0-cdh5.4.2/etc/hadoop --script /opt/hadoop/sbin/hdfs start datanode' 
#START YARN
sudo -H -u yarn bash -c 'export JAVA_HOME=/opt/java; cd /opt/hadoop-2.6.0-cdh5.4.2 ; /opt/hadoop/sbin/yarn-daemon.sh --config /opt/hadoop-2.6.0-cdh5.4.2/etc/hadoop start nodemanager' 
#STOP DATANODE
sudo -H -u hdfs bash -c 'export JAVA_HOME=/opt/java; cd /opt/hadoop-2.6.0-cdh5.4.2 ; /opt/hadoop-2.6.0-cdh5.4.2/sbin/hadoop-daemon.sh --config /opt/hadoop-2.6.0-cdh5.4.2/etc/hadoop --script /opt/hadoop/sbin/hdfs stop datanode' 
#STOP YARN
sudo -H -u yarn bash -c 'export JAVA_HOME=/opt/java; cd /opt/hadoop-2.6.0-cdh5.4.2 ; /opt/hadoop/sbin/yarn-daemon.sh --config /opt/hadoop-2.6.0-cdh5.4.2/etc/hadoop stop nodemanager' 
}}}