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Unable to Connect to a Listener Using Only Localhost or Loopback IP 127.0.0.1 ORA-12541 or TNS-12541 (Doc ID 279608.1)

Last updated on MARCH 19, 2019

Applies to:

Oracle Net Services - Version 9.2.0.5 to 12.1.0.1 [Release 9.2 to 12.1]
Information in this document applies to any platform.
This problem can occur on any platform.
Remote clients attempting to connect to a database via a listener started up on localhost.

Symptoms

Beginning with listener version 9.2.0.5.0, remote clients attempting to connect to a database via a listener started up on localhost will encounter the error ORA-12541 - no listener. Tnsping also fails with the same error.

If a 9.2.0.4.0 or older version of listener is used, and started up on localhost, remote users are able to connect via that listener as well as tnsping

Cause

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In this Document
Symptoms
Cause
Solution
References

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