title: Error in starting namenode in hadoop 2.4.1
body: <p>When I try to start dfs using:</p>
  
  <pre><code>start-dfs.sh
  </code></pre>
  
  <p>I get an error saying :</p>
  
  <pre><code>14/07/03 11:03:21 WARN util.NativeCodeLoader: Unable to load
  native-hadoop library for your platform... using builtin-java classes
  where applicable Starting namenodes on [OpenJDK 64-Bit Server VM
  warning: You have loaded library
  /usr/local/hadoop/lib/native/libhadoop.so.1.0.0 which might have
  disabled stack guard. The VM will try to fix the stack guard now. It's
  highly recommended that you fix the library with 'execstack -c
  &lt;libfile&gt;', or link it with '-z noexecstack'. localhost] sed: -e
  expression #1, char 6: unknown option to `s' Server: ssh: Could not
  resolve hostname Server: Name or service not known
  -c: Unknown cipher type 'cd' stack: ssh: Could not resolve hostname stack: Name or service not known 64-Bit: ssh: Could not resolve
  hostname 64-Bit: Name or service not known guard.: ssh: Could not
  resolve hostname guard.: Name or service not known The: ssh: Could not
  resolve hostname The: Name or service not known guard: ssh: Could not
  resolve hostname guard: Name or service not known might: ssh: Could
  not resolve hostname might: Name or service not known stack: ssh:
  Could not resolve hostname stack: Name or service not known will: ssh:
  Could not resolve hostname will: Name or service not known the: ssh:
  Could not resolve hostname the: Name or service not known fix: ssh:
  Could not resolve hostname fix: Name or service not known VM: ssh:
  Could not resolve hostname VM: Name or service not known You: ssh:
  Could not resolve hostname You: Name or service not known which: ssh:
  Could not resolve hostname which: Name or service not known It's: ssh:
  Could not resolve hostname It's: Name or service not known disabled:
  ssh: Could not resolve hostname disabled: Name or service not known
  try: ssh: Could not resolve hostname try: Name or service not known
  localhost: namenode running as process 4463. Stop it first. library:
  ssh: Could not resolve hostname library: Name or service not known
  with: ssh: Could not resolve hostname with: Name or service not known
  the: ssh: Could not resolve hostname the: Name or service not known
  warning:: ssh: Could not resolve hostname warning:: Name or service
  not known VM: ssh: Could not resolve hostname VM: Name or service not
  known now.: ssh: Could not resolve hostname now.: Name or service not
  known loaded: ssh: Could not resolve hostname loaded: Name or service
  not known library: ssh: Could not resolve hostname library: Name or
  service not known &lt;libfile&gt;',: ssh: Could not resolve hostname
  &lt;libfile&gt;',: Name or service not known to: ssh: connect to host to
  port 22: Connection refused OpenJDK: ssh: Could not resolve hostname
  OpenJDK: Name or service not known have: ssh: Could not resolve
  hostname have: Name or service not known have: ssh: Could not resolve
  hostname have: Name or service not known with: ssh: Could not resolve
  hostname with: Name or service not known fix: ssh: Could not resolve
  hostname fix: Name or service not known noexecstack'.: ssh: Could not
  resolve hostname noexecstack'.: Name or service not known that: ssh:
  Could not resolve hostname that: Name or service not known you: ssh:
  Could not resolve hostname you: Name or service not known or: ssh:
  Could not resolve hostname or: Name or service not known highly: ssh:
  Could not resolve hostname highly: Name or service not known
  recommended: ssh: Could not resolve hostname recommended: Name or
  service not known 'execstack: ssh: Could not resolve hostname
  'execstack: Name or service not known link: ssh: Could not resolve
  hostname link: Name or service not known it: ssh: Could not resolve
  hostname it: Name or service not known '-z: ssh: Could not resolve
  hostname '-z: Name or service not known localhost: datanode running as
  process 4561. Stop it first. Starting secondary namenodes [OpenJDK
  64-Bit Server VM warning: You have loaded library
  /usr/local/hadoop/lib/native/libhadoop.so.1.0.0 which might have
  disabled stack guard. The VM will try to fix the stack guard now. It's
  highly recommended that you fix the library with 'execstack -c
  &lt;libfile&gt;', or link it with '-z noexecstack'.
  0.0.0.0] sed: -e expression #1, char 6: unknown option to `s' OpenJDK: ssh: Could not resolve hostname OpenJDK: Name or service not known
  -c: Unknown cipher type 'cd' VM: ssh: Could not resolve hostname VM: Name or service not known The authenticity of host '0.0.0.0 (0.0.0.0)'
  can't be established. ECDSA key fingerprint is
  dd:64:53:7e:c0:62:40:c0:63:2b:5c:6d:1e:b6:cd:23. Are you sure you want
  to continue connecting (yes/no)? might: ssh: Could not resolve
  hostname might: Name or service not known Server: ssh: Could not
  resolve hostname Server: Name or service not known guard.: ssh: Could
  not resolve hostname guard.: Name or service not known have: ssh:
  Could not resolve hostname have: Name or service not known You: ssh:
  Could not resolve hostname You: Name or service not known The: ssh:
  Could not resolve hostname The: Name or service not known which: ssh:
  Could not resolve hostname which: Name or service not known have: ssh:
  Could not resolve hostname have: Name or service not known disabled:
  ssh: Could not resolve hostname disabled: Name or service not known
  VM: ssh: Could not resolve hostname VM: Name or service not known
  It's: ssh: Could not resolve hostname It's: Name or service not known
  fix: ssh: Could not resolve hostname fix: Name or service not known
  the: ssh: Could not resolve hostname the: Name or service not known
  warning:: ssh: Could not resolve hostname warning:: Name or service
  not known will: ssh: Could not resolve hostname will: Name or service
  not known the: ssh: Could not resolve hostname the: Name or service
  not known library: ssh: Could not resolve hostname library: Name or
  service not known that: ssh: Could not resolve hostname that: Name or
  service not known highly: ssh: Could not resolve hostname highly: Name
  or service not known 'execstack: ssh: Could not resolve hostname
  'execstack: Name or service not known try: ssh: Could not resolve
  hostname try: Name or service not known guard: ssh: Could not resolve
  hostname guard: Name or service not known 64-Bit: ssh: Could not
  resolve hostname 64-Bit: Name or service not known loaded: ssh: Could
  not resolve hostname loaded: Name or service not known library: ssh:
  Could not resolve hostname library: Name or service not known fix:
  ssh: Could not resolve hostname fix: Name or service not known to:
  ssh: connect to host to port 22: Connection refused link: ssh: Could
  not resolve hostname link: Name or service not known stack: ssh: Could
  not resolve hostname stack: Name or service not known '-z: ssh: Could
  not resolve hostname '-z: Name or service not known you: ssh: Could
  not resolve hostname you: Name or service not known with: ssh: Could
  not resolve hostname with: Name or service not known with: ssh: Could
  not resolve hostname with: Name or service not known recommended: ssh:
  Could not resolve hostname recommended: Name or service not known
  stack: ssh: Could not resolve hostname stack: Name or service not
  known now.: ssh: Could not resolve hostname now.: Name or service not
  known &lt;libfile&gt;',: ssh: Could not resolve hostname &lt;libfile&gt;',: Name
  or service not known or: ssh: Could not resolve hostname or: Name or
  service not known noexecstack'.: ssh: Could not resolve hostname
  noexecstack'.: Name or service not known it: ssh: Could not resolve
  hostname it: Name or service not known ^C0.0.0.0: Host key
  verification failed. ^C
  </code></pre>
  
  <p>My core-site.xml file contains this:</p>
  
  <pre><code>&lt;configuration&gt;
      &lt;property&gt;
         &lt;name&gt;fs.default.name&lt;/name&gt;
         &lt;value&gt;hdfs://localhost:9000&lt;/value&gt;
      &lt;/property&gt;
  &lt;/configuration&gt;
  </code></pre>
  
  <p>My <code>.profile</code> (replacement for <code>.bashrc</code>) contains these lines:</p>
  
  <pre><code>export JAVA_HOME=/usr/lib/jvm/java-7-openjdk-amd64
  export HADOOP_INSTALL=/usr/local/hadoop
  export PATH=$PATH:$HADOOP_INSTALL/bin
  export PATH=$PATH:$HADOOP_INSTALL/sbin
  export HADOOP_MAPRED_HOME=$HADOOP_INSTALL
  export HADOOP_COMMON_HOME=$HADOOP_INSTALL
  export HADOOP_HDFS_HOME=$HADOOP_INSTALL
  export YARN_HOME=$HADOOP_INSTALL
  export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_INSTALL/lib/native
  export HADOOP_OPTS="-Djava.library.path=$HADOOP_INSTALL/lib"
  </code></pre>
  
  <p>And I can easily ssh my localhost saying:</p>
  
  <pre><code>ssh localhost
  
  Welcome to Linux Mint 16 Petra (GNU/Linux
  3.11.0-12-generic x86_64)
  
  Welcome to Linux Mint  * Documentation:  http://www.linuxmint.com Last
  login: Wed Jul  2 16:51:15 2014 from localhost
  </code></pre>