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OUD - Security TroubleShooting - Debugging SSL Connection Using the "openssl s_client" Command (Doc ID 1396054.1)

Last updated on MAY 31, 2023

Applies to:

Oracle Unified Directory - Version and later
Information in this document applies to any platform.


The goal of this document is to explain how to debug an SSL connection using the openssl s_client command.

The openssl s_client command implements a generic SSL/TLS client which connects to a host using SSL/TLS.

For more info -
Debugging SSL Using OpenSSL s_client Test Utility


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In this Document
 1) The openssl s_client command
 2) Symptom: Connection refused
 3) Symptom:  Verify return code: 18 (self signed certificate)
 4) Example of when the openssl client connects successfully to OUD (Verify return code: 0 (ok))

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