Hadoop NameNode does not start

Question

I am currently trying to run Hadoop 2.6.0 on Amazon EC2 instances (multi-node cluster). I launch two Ubuntu 14.04 instances. One of them as master and the other as slave. The following is my configuration:

Master

-core-site.xml

<configuration>
        <property>
                <name>fs.defaultFS</name>
                <value>hdfs://hadoopmaster:9000</value>
        </property>
</configuration>

-hdfs-site.xml

<configuration>
        <property>
                <name>dfs.replication</name>
                <value>1</value>
        </property>
        <property>
                <name>dfs.namenode.name.dir</name>
                <value>file:/home/ubuntu/hadoop-2.6.0/hadoop_data/hdfs/namenode</value>
        </property>
</configuration>

-yarn-site.xml

<property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
</property>
<property>
        <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>
        <value>org.apache.hadoop.mapred.ShuffleHandler</value>
</property>
<property>
        <name>yarn.resourcemanager.resource-tracker.address</name>
        <value>hadoopmaster:8025</value>
</property>
<property>
        <name>yarn.resourcemanager.scheduler.address</name>
        <value>hadoopmaster:8030</value>
</property>
<property>
        <name>yarn.resourcemanager.address</name>
        <value>hadoopmaster:8050</value>
</property>

-mapred-site.xml

<configuration>
        <property>
                <name>mapred.job.tracker</name>
                <value>hadoopmaster:54311</value>
        </property>
</configuration>

-masters

hadoopmaster

-slaves

hadoopslave1

Slave

-hdfs-site.xml

<configuration>
        <property>
                <name>dfs.replication</name>
                <value>1</value>
        </property>
        <property>
                <name>dfs.datanode.data.dir</name>
                <value>file:/home/ubuntu/hadoop-2.6.0/hadoop_data/hdfs/datanode</value>
        </property>
</configuration>

Others are the same as master.

When I run hdfs namenode -format it looks fine and exit with status 0. When I run start-all.sh it gives the following output:

ubuntu@hadoopmaster:~/hadoop-2.6.0$ sbin/start-all.sh 
This script is Deprecated. Instead use start-dfs.sh and start-yarn.sh
Starting namenodes on [hadoopmaster]
hadoopmaster: starting namenode, logging to /home/ubuntu/hadoop-2.6.0/logs/hadoop-ubuntu-namenode-hadoopmaster.out
hadoopslave1: starting datanode, logging to /home/ubuntu/hadoop-2.6.0/logs/hadoop-ubuntu-datanode-hadoopslave1.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /home/ubuntu/hadoop-2.6.0/logs/hadoop-ubuntu-secondarynamenode-hadoopmaster.out
starting yarn daemons
starting resourcemanager, logging to /home/ubuntu/hadoop-2.6.0/logs/yarn-ubuntu-resourcemanager-hadoopmaster.out
hadoopslave1: starting nodemanager, logging to /home/ubuntu/hadoop-2.6.0/logs/yarn-ubuntu-nodemanager-hadoopslave1.out

It sounds good and no error reported. However, when I run jps on the master site, it gives the following output:

ubuntu@hadoopmaster:~/hadoop-2.6.0$ jps
3640 ResourceManager
3501 SecondaryNameNode
3701 Jps

The NameNode is missing! When I run jps on slave site, I got the following

ubuntu@hadoopslave1:~/hadoop-2.6.0$ jps
1686 DataNode
1870 Jps
1817 NodeManager

Following is the log file for NameNode:

2015-06-11 04:16:18,987 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG:   host = hadoopmaster/54.172.40.127
STARTUP_MSG:   args = []
STARTUP_MSG:   version = 2.6.0

and the .out file:

ulimit -a for user ubuntu
core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 13357
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 1024
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 13357
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

I have repeated this several times and I got the same result. The NameNode is always missing. Could anyone give me some suggestion about this problem? Thank you so much!

Answer 1

Did you check the permissions for the folders under the path file:/home/ubuntu/hadoop-2.6.0/hadoop_data/hdfs/

Answer 2

I am guessing you already figured out the solution but this is for anyone else that stumbles across this with the same problem(Like me).

First bring down your hadoop cluster using stop-yarn.sh and stop-dfs.sh (In that order). Now all you have to do is go to the hadoop temp directory. If not configured by you the user, then it will be in /usr/local/hadoop/tmp/.

Else find it from the core-site.xml from the propery hadoop.tmp.dir. Then simply type:

rm -rf *

Now start the cluster up and viola, Namenode is started.