title: Unable to start Oracle
body: <p>I installed the latest version of Oracle 11g on Centos 6.3. But for some reason I cannot connect to SQL plus. This is the content of listener.ora:</p>
  
  <pre><code># listener.ora Network Configuration File: /u01/app/oracle/product/11.2.0/dbhome_1/network/admin/listener.ora
  # Generated by Oracle configuration tools.
  
  LISTENER =
    (DESCRIPTION_LIST =
      (DESCRIPTION =
        (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
        (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.104)(PORT = 1521))
      )
    )
  
  ADR_BASE_LISTENER = /u01/app/oracle
  </code></pre>
  
  <p>I type this into the shell:</p>
  
  <pre><code>[oracle@localhost bin]$ ./lsnrctl start
  
  LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 07-JAN-2013 21:37:32
  
  Copyright (c) 1991, 2009, Oracle.  All rights reserved.
  
  Starting /u01/app/oracle/product/11.2.0/dbhome_1//bin/tnslsnr: please wait...
  
  TNSLSNR for Linux: Version 11.2.0.1.0 - Production
  System parameter file is /u01/app/oracle/product/11.2.0/dbhome_1/network/admin/listener.ora
  Log messages written to /u01/app/oracle/diag/tnslsnr/localhost/listener/alert/log.xml
  Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
  Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.1.104)(PORT=1521)))
  
  Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
  STATUS of the LISTENER
  ------------------------
  Alias                     LISTENER
  Version                   TNSLSNR for Linux: Version 11.2.0.1.0 - Production
  Start Date                07-JAN-2013 21:37:32
  Uptime                    0 days 0 hr. 0 min. 0 sec
  Trace Level               off
  Security                  ON: Local OS Authentication
  SNMP                      OFF
  Listener Parameter File   /u01/app/oracle/product/11.2.0/dbhome_1/network/admin/listener.ora
  Listener Log File         /u01/app/oracle/diag/tnslsnr/localhost/listener/alert/log.xml
  Listening Endpoints Summary...
    (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
    (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.1.104)(PORT=1521)))
  The listener supports no services
  The command completed successfully
  [oracle@localhost bin]$ 
  </code></pre>
  
  <p>And then I try to start SQL plus this:</p>
  
  <pre><code>[oracle@localhost bin]$ ./sqlplus sys@oracle AS SYSDBA
  
  SQL*Plus: Release 11.2.0.1.0 Production on Mon Jan 7 21:38:27 2013
  
  Copyright (c) 1982, 2009, Oracle.  All rights reserved.
  
  Enter password: 
  ERROR:
  ORA-12154: TNS:could not resolve the connect identifier specified
  
  
  Enter user-name: 
  </code></pre>
  
  <p>How I can solve this problem?</p>