Not Able to Login to Oracle Database from SQL*Plus


# The problem

When you try to login to Oracle database through SQL*Plus, you get the error:

bash Error : ORA-12514 : TNS: Listener does not currently know of the service requested in connect descriptor.


Check the following:

  • You setup correctly the listener.
  • ORACLE_SID is the correct one.


  1. export ORACLE_SID= Where is the name that you have given during database installation.
  2. sqlplus "/as sysdba"