ORA-12523 or ORA-12541 connecting remote client to 12.2 Database (Doc ID 2320190.1)

Last updated on NOVEMBER 02, 2017

Applies to:

Oracle Net Services - Version 12.2.0.1 and later
Information in this document applies to any platform.

Symptoms

SQL*Plus connections from a remote 12.2 Client to 12.2 Database fail:
ORA-12523: TNS:listener could not find instance appropriate for the client connection

Local connections through the same listener work.

Cause

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