ORA-12534: TNS:operation not supported


Sometimes You can get “ORA-12534: TNS:operation not supported ” error.


Details of error are as follows.

ORA-12534: TNS:operation not supported
Cause: An internal function received a request to perform an operation that is not supported (on this machine).
Action: Not normally visible to the user. For further details, turn on tracing and reexecute the operation.
If error persists, contact Oracle Customer Support.


This error is related with incorrect syntax or spaces or closing bracket.


Password authentication (sqlplus <user>/<password>@<TNS alias>) works fine from client machine.

The same <user>, <password>, <TNS alias> credentials were stored in the Secure External Password Store Wallet file.

But the connection using External Password Store Wallet (sqlplus /@<TNS alias>) errors out every time with ‘ORA-12534: TNS:operation not supported’

Wallet configuration was correct according to the document (Doc ID 340559.1)


Upon research, it was found that the OS user setup was different and was not having same permission and group as was needed.

Once corrected, this worked fine.


Check the /etc/passwd file for the OS user details and make sure the user is setup correctly.

Also check the /etc/group file for the user group details.


You will also need to check your environment variables if that is set correctly, if not explicitly set the correct values and then try to connect again.

set ORACLE_HOME=<appropriate value>
set ORACLE_SID=<appropriate value>
set TNS_ADMIN=<appropriate value>

export ORACLE_HOME=/u01/app/product/12.2.0/dbhome_1
export TNS_ADMIN=/u01/app/product/12.2.0/dbhome_1/network/admin


Try connecting again


sqlplus “/ as sysdba”


Do you want to learn more details about RMAN, then read the following articles.



About Mehmet Salih Deveci

I am Founder of SysDBASoft IT and IT Tutorial and Certified Expert about Oracle & SQL Server database, Goldengate, Exadata Machine, Oracle Database Appliance administrator with 10+years experience.I have OCA, OCP, OCE RAC Expert Certificates I have worked 100+ Banking, Insurance, Finance, Telco and etc. clients as a Consultant, Insource or Outsource.I have done 200+ Operations in this clients such as Exadata Installation & PoC & Migration & Upgrade, Oracle & SQL Server Database Upgrade, Oracle RAC Installation, SQL Server AlwaysOn Installation, Database Migration, Disaster Recovery, Backup Restore, Performance Tuning, Periodic Healthchecks.I have done 2000+ Table replication with Goldengate or SQL Server Replication tool for DWH Databases in many clients.If you need Oracle DBA, SQL Server DBA, APPS DBA,  Exadata, Goldengate, EBS Consultancy and Training you can send my email adress [email protected].-                                                                                                                                                                                                                                                 -Oracle DBA, SQL Server DBA, APPS DBA,  Exadata, Goldengate, EBS ve linux Danışmanlık ve Eğitim için  [email protected] a mail atabilirsiniz.

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