ORA-12154: TNS:could not resolve the connect identifier specified
 *Cause:  A connection to a database or other service was requested using
 a connect identifier, and the connect identifier specified could not
 be resolved into a connect descriptor using one of the naming methods
 configured. For example, if the type of connect identifier used was a
 net service name then the net service name could not be found in a
 naming method repository, or the repository could not be
 located or reached.
 *Action:
   - If you are using local naming (TNSNAMES.ORA file):
      - Make sure that "TNSNAMES" is listed as one of the values of the
        NAMES.DIRECTORY_PATH parameter in the Oracle Net profile
        (SQLNET.ORA)
      - Verify that a TNSNAMES.ORA file exists and is in the proper
        directory and is accessible.
      - Check that the net service name used as the connect identifier
        exists in the TNSNAMES.ORA file.
      - Make sure there are no syntax errors anywhere in the TNSNAMES.ORA
        file.  Look for unmatched parentheses or stray characters. Errors
        in a TNSNAMES.ORA file may make it unusable.
   - If you are using directory naming:
      - Verify that "LDAP" is listed as one of the values of the
        NAMES.DIRETORY_PATH parameter in the Oracle Net profile
        (SQLNET.ORA).
      - Verify that the LDAP directory server is up and that it is
        accessible.
      - Verify that the net service name or database name used as the
        connect identifier is configured in the directory.
      - Verify that the default context being used is correct by
        specifying a fully qualified net service name or a full LDAP DN
        as the connect identifier
   - If you are using easy connect naming:
      - Verify that "EZCONNECT" is listed as one of the values of the
        NAMES.DIRETORY_PATH parameter in the Oracle Net profile
        (SQLNET.ORA).
      - Make sure the host, port and service name specified
        are correct.
      - Try enclosing the connect identifier in quote marks.

   See the Oracle Net Services Administrators Guide or the Oracle
   operating system specific guide for more information on naming.

local.world = 
  (DESCRIPTION = 
    (ADDRESS_LIST = 
        (ADDRESS = 
          (COMMUNITY = tcp.world)
          (PROTOCOL = TCP)
          (Host = 127.0.0.1)
          (Port = 1521)
        )
        (ADDRESS = 
          (COMMUNITY = tcp.world)
          (PROTOCOL = TCP)
          (Host = 127.0.0.1)
          (Port = 1526)
        )
    )
    (CONNECT_DATA = (SID = ORCL)
    )
  )

C:\orant\NETWORK\ADMIN>tnsping local

TNS Ping Utility for 32-bit Windows: Version 11.2.0.1.0 - Production on 23-AUG-2
011 20:07:11

Copyright (c) 1997, 2010, Oracle.  All rights reserved.

Used parameter files:
C:\app\Abadi\product\11.2.0\dbhome_1\network\admin\sqlnet.ora


Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)
(HOST = 127.0.0.1)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = ORCL)))
OK (10 msec)

oracle@bcm-laptop:~$ lsnrctl start

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 23-AUG-2011 09:56:54

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/bcm-laptop/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(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                23-AUG-2011 09:56:56
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/bcm-laptop/listener/alert/log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521)))
Services Summary...
Service "v112" has 1 instance(s).
  Instance "v112", status UNKNOWN, has 1 handler(s) for this service...
The command completed successfully
oracle@bcm-laptop:~$ tnsping v112

TNS Ping Utility for Linux: Version 11.2.0.1.0 - Production on 23-AUG-2011 09:57:11

Copyright (c) 1997, 2009, Oracle.  All rights reserved.

Used parameter files:
/u01/app/oracle/product/11.2.0/dbhome_1/network/admin/sqlnet.ora


Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=V112)))
OK (40 msec)
oracle@bcm-laptop:~$ sqlplus hr/hr@v112

SQL*Plus: Release 11.2.0.1.0 Production on Tue Aug 23 09:57:35 2011

Copyright (c) 1982, 2009, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

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