#!/bin/sh
# Start Hadoop on a cluster.

# Import variables
bin=`dirname "$0"`
bin=`cd "$bin"; pwd`
. "$bin"/hadoop-ec2-env.sh

echo "Asking master to say hello"
if ! ssh $SSH_OPTS "root@$MASTER_HOST" echo "hello" ; then
  echo "SSH failed for root@$MASTER_HOST"
  exit 1
fi

# Datanodes that are started separately from the rest of the cluster will
# still use the $MASTER_HOST address to access the master
echo "Adjusting master hadoop-site.xml to minimize DNS lookups"
ssh $SSH_OPTS "root@$MASTER_HOST" "sed -i -e \"s/$MASTER_HOST/\$(hostname)/g\" /usr/local/hadoop-$HADOOP_VERSION/conf/hadoop-site.xml"

echo "Creating slaves file and copying to master"
ec2-describe-instances | grep INSTANCE | grep running | awk '{if ($7 != 0 && $8 != 0) print $4}' > slaves
scp $SSH_OPTS slaves "root@$MASTER_HOST:/usr/local/hadoop-$HADOOP_VERSION/conf/slaves"

echo "Copying private key to master"
scp $SSH_OPTS $PRIVATE_KEY_PATH "root@$MASTER_HOST:/root/.ssh/id_rsa"
ssh $SSH_OPTS "root@$MASTER_HOST" "chmod 600 /root/.ssh/id_rsa"

echo "Copying private key to slaves"
for slave in `cat slaves`; do
  scp $SSH_OPTS $PRIVATE_KEY_PATH "root@$slave:/root/.ssh/id_rsa"
  ssh $SSH_OPTS "root@$slave" "chmod 600 /root/.ssh/id_rsa"
  sleep 1
done

echo "Formatting new cluster's filesystem"
ssh $SSH_OPTS "root@$MASTER_HOST" "/usr/local/hadoop-$HADOOP_VERSION/bin/hadoop namenode -format"

echo "Starting cluster"
ssh $SSH_OPTS "root@$MASTER_HOST" "/usr/local/hadoop-$HADOOP_VERSION/bin/start-all.sh"

echo "Finished - check progress at http://$MASTER_HOST:50030/"

echo "Logging in to master $MASTER_HOST."
ssh $SSH_OPTS "root@$MASTER_HOST"