Cause: The connect descriptor corresponding to the net service name in TNSNAMES.ORA or in the directory server (Oracle Internet Directory) is incorrectly specified.
Action: If using local naming make sure there are no syntax errors in the corresponding connect descriptor in the TNSNAMES.ORA file. If using directory naming check the information provided through the administration used for directory naming.
Example:
oracle@hostname:~$ sqlplus scott
SQL*Plus: Release 11.2.0.1.0 Production on Wed Feb 26 15:34:14 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Enter password:
ERROR:
ORA-12162: TNS:net service name is incorrectly specified
Solution:
Windows:
set ORACLE_SID=scotttest
Linux:
Set oracle home if not set, you can check it by “echo $ORACLE_HOME”
oracle@hostname:~$ export ORACLE_HOME=/opt/oracle/product/ora11r2
oracle@hostname:~$ export ORACLE_SID=scotttest
oracle@hostname:~$ sqlplus scott
SQL*Plus: Release 11.2.0.1.0 Production on Wed Feb 26 15:39:22 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Enter password:
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning and Automatic Storage Management options
SQL>
If you are using TNS files then you can check your TNS by the following way:
oracle@hostname:~$ sqlplus scott@scott_test
SQL*Plus: Release 11.2.0.1.0 Production on Wed Feb 26 15:44:13 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Enter password:
ERROR:
ORA-12505: TNS:listener does not currently know of SID given in connect descriptor
Fix the TNS information in tnsnames.ora file and check it.
oracle@hostname:~$ tnsping scott_test
TNS Ping Utility for Linux: Version 11.2.0.1.0 - Production on 26-FEB-2014 15:45:54
Copyright (c) 1997, 2009, Oracle. All rights reserved.
Used parameter files:
/opt/oracle/product/ora11r2/network/admin/sqlnet.ora
Used TNSNAMES adapter to resolve the alias
Attempting to contact (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = host.scott.com)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SID = scotttest)))
OK (0 msec)
Now it should Work.
oracle@hostname:~$ sqlplus scott@scott_test
SQL*Plus: Release 11.2.0.1.0 Production on Wed Feb 26 15:45:36 2014
Copyright (c) 1982, 2009, Oracle. All rights reserved.
Enter password:
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, Automatic Storage Management, OLAP, Data Mining
and Real Application Testing options
SQL>
Note: If you are using client and tnping is not working then check your client have installed that features or not. Usually you will get tnsping.exe file under bin folder if this features installed.