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Remote Connections Via the Listener to the Database Fail with TNS-12526, TNS-12527 or TNS-12528 (Doc ID 444120.1)

Last updated on AUGUST 28, 2023

Applies to:

Oracle Net Services - Version to [Release 10.2 to 12.2]
Information in this document applies to any platform.


Connections via the listener to an instance that is in RESTRICTED status or in NO MOUNT status may fail with TNS-12526, TNS-12527 or TNS-12528 even when supplying the credentials for a privileged account.    The lsnrctl services output will show that the service handler for this instance is in state: BLOCKED or RESTRICTED.

The full error text is:


From the above we can see that the listener status for that instance is


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