Hello Experts,
The BI & Test team facing the following error: " ORA-12520: TNS:listener could not find available handler for requested type of server" , after upgrading the db from 11.2.0.4 to 12.1.0.3 and the GI version is 19.0.0.0.0 .
My troubleshooting was as following:
I have checked the local listeners for both nodes and they were correct.
I have checked the registered services
I have checked the Listener status to check the handler's value and it wasn't 0 " 0 handler(s) for this service..." it was 1 normally as following : " has 1 handler(s) for this service ".
knowing that the issue It does not happen continuously but occurring from time to other but it causing service interruption.
Please advise.
Regards,
Haytham