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TNS-12520 connecting via the Listener and Service shows as "Blocked" and Oracle SQL Tuning Advisor is running (Doc ID 1934932.1)

Last updated on JANUARY 17, 2025

Applies to:

Oracle Net Services - Version 11.1.0.7 and later
Gen 2 Exadata Cloud at Customer - Version N/A and later
Oracle Cloud Infrastructure - Exadata Cloud Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Database - Enterprise Edition - Version 19.15.1.0.0 and later
Information in this document applies to any platform.

Symptoms

When attempting to connect to the Database instance via the Listener, you receive a TNS-12520 or TNS-12519 error.

A check of the listener status or services shows that the Service is "Blocked"

Cause

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In this Document
Symptoms
Cause
Solution
References


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