= Deploy Hadoop to PC Classroom using DRBL =

 * java is required for Hadoop, so you need to install java runtime or jdk first.
{{{
~$ echo "deb http://free.nchc.org.tw/debian/ etch non-free" > /tmp/etch-non-free.list
~$ sudo mv /tmp/etch-non-free.list /etc/apt/sources.list.d/.
~$ sudo apt-get update
~$ sudo apt-get install sun-java5-jdk
}}}
 * download Hadoop 0.18.2 
{{{
~$ wget http://ftp.twaren.net/Unix/Web/apache/hadoop/core/hadoop-0.18.2/hadoop-0.18.2.tar.gz
~$ tar zxvf hadoop-0.18.2.tar.gz
}}}
 * setup JAVA_HOME environment variable
{{{
~$ echo "export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun" >> ~/.bash_profile
~$ source ~/.bash_profile
}}}
 * edit hadoop-0.18.2/conf/hadoop-env.sh
{{{
#!diff
--- hadoop-0.18.2/conf/hadoop-env.sh.org        2008-11-06 22:57:40.000000000 +0800
+++ hadoop-0.18.2/conf/hadoop-env.sh    2008-11-06 22:58:42.000000000 +0800
@@ -6,7 +6,9 @@
 # remote nodes.

 # The java implementation to use.  Required.
-# export JAVA_HOME=/usr/lib/j2sdk1.5-sun
+export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun
+export HADOOP_HOME=/home/jazz/hadoop-0.18.2
+export HADOOP_CONF_DIR=$HADOOP_HOME/conf

 # Extra Java CLASSPATH elements.  Optional.
 # export HADOOP_CLASSPATH=
}}}
 * here is current DRBL setup
{{{
          NIC    NIC IP                    Clients
+------------------------------+
|         DRBL SERVER          |
|                              |
|    +-- [eth0] X.X.X.X        +- to WAN
|                              |
|    +-- [eth1] 192.168.61.254 +- to clients group 1 [ 10 clients, their IP
|                              |             from 192.168.61.1 - 192.168.61.10]
|    +-- [eth2] 192.168.62.254 +- to clients group 2 [ 11 clients, their IP
|                              |             from 192.168.62.1 - 192.168.62.11]
|    +-- [eth3] 192.168.63.254 +- to clients group 3 [ 10 clients, their IP
|                              |             from 192.168.63.1 - 192.168.63.10]
|    +-- [eth4] 192.168.64.254 +- to clients group 4 [ 10 clients, their IP
|                              |             from 192.168.64.1 - 192.168.64.10]
+------------------------------+
}}}
 * Hadoop will use ssh connections for internal connection, thus we have to do SSH key exchange.
{{{
~$ ssh-keygen
~$ cp .ssh/id_rsa.pub .ssh/authorized_keys
~$ sudo apt-get install dsh
~$ mkdir -p .dsh
~$ nmap -v -sP 192.168.61-63.1-11 | grep '(.*) .* up' | awk '{ print $3 }' | sort -n | sed 's#(##' | sed 's#)##' > .dsh/machines.list"192.168.63.$i" >> .dsh/machines.list; echo "192.168.64.$i" >> .dsh/machines.list; done
}}}
 * edit