ORA-12162: TNS:net service name is incorrectly specified

[oracle@ oracle]$ sqlplus

SQL*Plus: Release 11.2.0.1.0 Production on Tue Oct 11 20:53:19 2011

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

Enter user-name: sys as sysdba

ORA-12162: TNS:net service name is incorrectly specified

Solution:

This is because ORACEL_SID value is not set for database name before connecting to database.

[oracle@bin]$ export ORACLE_SID=icind

[oracle@bin]$ sqlplus

SQL*Plus: Release 11.2.0.1.0 Production on Tue Oct 11 20:54:00 2011

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

Enter user-name: username

Enter password:*******

Connected to:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

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