title: ORA-12547: TNS Lost Contact when running DBCA on Oracle 11g installation on Ubuntu Linux 12.04 64 bit
body: <p>I'm trying to create a database using DBCA on Oracle 11g installation on Ubuntu Linux 12.04 64 bit.</p>
  
  <p>I followed the instructions <a href="http://www.makina-corpus.org/blog/howto-install-oracle-11g-ubuntu-linux-1204-precise-pangolin-64bits" rel="nofollow">here</a>, but I get  </p>
  
  <blockquote>
    <p>ORA-12547: TNS Lost Contact when running DBCA.</p>
  </blockquote>
  
  <p>Below are the details.  Can someone assist with the solution?</p>
  
  <ol>
  <li><p>Instead of using <code>/opt/oracle</code>  as the "oracle" user home, I used  <code>/home/oracle</code></p></li>
  <li><p>I did not install the libstdc++5 in 32 bit version</p></li>
  <li><p>I did everything else the same as the posting</p></li>
  <li><p>Installation resulted in "missing packages".  I tried to do an   apt-get install for these packages from ubuntu, but ubuntu says that they don't exist.
  Then I saw in the instructions:</p>
  
  <blockquote>
    <p>Once you will reach the "pre-reqs" screen, check "Ignore all" to continue the installation.  </p>
  </blockquote></li>
  <li><p>When running <code>./dbca</code> from <code>$ORACLE_HOME/bin</code>, it fails with ORA-12547.</p></li>
  <li><p>I checked <code>$ORACLE_HOME/network/admin</code> and listener.ora , sqlnet.ora , and tnsnames.ora  all look OK.</p></li>
  <li><p>However, I think that tnsnames.ora  is not being read properly, because  <code>./tnsping</code>  fails and the error message states that "EZ Connect" was used.
  But in my sqlnet.ora , I have</p>
  
  <pre><code>names.directory_lookup = (TNSNAMES,EZCONNECT)
  </code></pre>
  
  <p>It should use EZ Connect only after tnsnames is tried.</p></li>
  <li><p>Also, I sometimes get ORA-12541: No listener. I tried running <code>./netca</code>.  Everything is OK until I perform a test on the listener, and it fails.</p></li>
  <li><p>I can't run  <code>./lsnrctl</code>. Absolutely nothing happens for this, as well as  lsnrctl start, stop, status.</p></li>
  <li><p>I can't go through sqlplus.   If I run <code>./sqlplus</code> , it asks me for username/password directly.</p></li>
  <li><p>If I do  <code>./sqlplus / as sysdba</code>, then this results in "ORA-12547: TNS lost contact".</p></li>
  <li><p>All environment variables are set correctly in <code>.bashrc</code>.</p></li>
  <li><p>I tried re-running root.sh , but the problem is not fixed.</p></li>
  <li><p><code>/etc/oratab</code>  is OK</p></li>
  <li><p><code>/etc/hosts</code>  is OK, but I can't always ping the "localhost" or "127.0.0.1", or "ubuntu" or "127.0.1.1"</p>
  
  <p>The same TNS or Listener errors display.</p></li>
  </ol>