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SYSDBA NTS Authentication Fails with ORA-12638 for Domain Accounts. (Doc ID 1320009.1)

Last updated on JANUARY 30, 2022

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


The SYSDBA authentication for a domain user fails with ORA-12638.
This issue can appear as well during service startup or during the server startup.
The first thing to attempt is to take sqlnet trace files for client and server.
After investigating the trace files, the following errors are found:

[22-FEB-2011 09:54:48:049] naun5authent: SSPI: 0x80090311 error in InitializeSecurityContext
[22-FEB-2011 09:54:48:049] naun5authent: exit
[22-FEB-2011 09:54:48:049] naunauthent: exit
[22-FEB-2011 09:54:48:049] nau_ccn: get credentials function failed
[22-FEB-2011 09:54:48:049] nau_ccn: failed with error 12638
[22-FEB-2011 09:54:48:049] nacomsd: entry
[22-FEB-2011 09:54:48:049] nacomfsd: entry
[22-FEB-2011 09:54:48:049] nacomfsd: exit
[22-FEB-2011 09:54:48:049] nacomsd: exit
[22-FEB-2011 09:54:48:049] nau_ccn: exit
[22-FEB-2011 09:54:48:049] na_csrd: failed with error 12638
[22-FEB-2011 09:54:48:049] na_csrd: exit
[22-FEB-2011 09:54:48:049] nacomer: error 12638 received from authentication service
[22-FEB-2011 09:54:48:049] nacomer: failed with error 12638

The error is returned by the AD controller and is documented on MS technet

No authenticating authority. Normally, this implies that the machine cannot contact a Domain Controller or from a Kerberos perspective (that is, a KDC). Troubleshoot this by turning on Kerberos Logging and getting a network monitor trace to determine where the computer is trying to contact for authentication. If you are traversing a trust then Netlogon log on Domain Controllers in both domains and if possible run a simultaneous trace to help pinpoint the failure."




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