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Internal Error Returned if OS_AUTHENT_PREFIX has a wrong value (Doc ID 282822.1)

Last updated on OCTOBER 10, 2022

Applies to:

Oracle Database Exadata Express Cloud Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.
This problem can occur on any platform.
ORA-00600 [15051] is returned when attempting to login with OS authentication if the parameter


The value of parameter OS_AUTHENT_PREFIX will be used by oracle for authenticating users connecting to the server. See <Note.30785.1>:'Init.ora Parameter "OS_AUTHENT_PREFIX" Reference Note'.

You can set this value to a null string as below.

Any value within the quotes will be prefixed to the user's operating system account name.

If OS_AUTHENT_PREFIX='X' and OS username is "APP", the user is termed as "XAPP" and then compared with the Oracle username in the database.

If a null string is used, there will be no prefix added to the OS username.

If OS_AUTHENT_PREFIX='""', value of the parameter is kept as "" in the database and Oracle fails with ORA-00600 [15051].


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