ORA-12514: TNS:listener does not currently know of service - Oracle Database

ORA-12514: TNS:listener does not currently know of service requested in connect descriptor

How to resolve ORA-12514 error? Tips to resolve ORA-12514 error in oracle database.

ORA-12514: TNS:listener does not currently know of service

This is one of the basic errors which you'll usually face in normal day to day oracle activities (if you are working in multiple oracle database environments). As per my working routine, normally I have to create at least one new database per day. It can be for creating a test environment for some client, for UAT or for some normal backup import testing. So in short, when you are dealing with multiple oracle databases environment, you are supposed to be familiar with this error.

What it means?

This error simply indicates that the listener is unaware of the database service which is requesting to make a connection with database. The reason can be simple, either one or both of the services are not completely started (are not in running state) OR the database is not registered with the listener.

Resolution:

(1) Make sure the listener and database services are up and running.

(2)  If the 1st one doesn't resolve your issue, then open NET MANAGER

oracle_database_net_manager_11g_database_entry_in_listener

and make the entry for the database which you are connecting with the proper location to your Oracle Home Directory and save the configuration.

After this reload your listener and your problem must have resolved.

Note:- In multiple oracle database and listener environments, there are chances that the system/server on which you are trying to fix the same issue is having multiple listener running on different ports. If the above solutions are not able to help you, please check the Port as well and make sure you have registered the database with the correct listener.

I hope this helps !!