Call now: 252-767-6166  
Oracle Training Oracle Support Development Oracle Apps

 E-mail Us
 Oracle Articles
New Oracle Articles

 Oracle Training
 Oracle Tips

 Oracle Forum
 Class Catalog

 Remote DBA
 Oracle Tuning
 Emergency 911
 RAC Support
 Apps Support
 Oracle Support

 SQL Tuning

 Oracle UNIX
 Oracle Linux
 Remote s
 Remote plans
 Application Server

 Oracle Forms
 Oracle Portal
 App Upgrades
 SQL Server
 Oracle Concepts
 Software Support

 Remote S


 Consulting Staff
 Consulting Prices
 Help Wanted!


 Oracle Posters
 Oracle Books

 Oracle Scripts

Don Burleson Blog 







_sys_logon_delay tips

Oracle Database Tips by Donald BurlesonMarch 3, 2015

Question:  How does 12c hidden parameter _sys_logon_delay work?

Answer:  The Oracle12c new feature _sys_logon_delay defines a failed logon delay for the sys user.   Rampant author and security guru Paul Wright shows this working example of the _sys_logon_delay parameter.  He notes that _sys_logon_delay=0 will disable this delay and that a higher value for sys_logon_delay will help disable a hack attacker as shown in this example:

while true;do sqlplus -S -L sys/wrongpw@orlin:1521/orcl3 as sysdba;sleep 0;done;

ORA-01017: invalid username/password; logon denied
8<; --- Slow steady pace between failed logons thus making remote brute force infeasible.

--can set to 0 to disable, or to higher value to slow down attacker, but needs a restart.
--e.g. alter system set "_sys_logon_delay"=0 scope=spfile;

SQL>; select banner from v$version;

Oracle Database 12c Enterprise Edition Release - 64bit Production
PL/SQL Release - Production
CORE Production
TNS for Linux: Version - Production
NLSRTL Version - Production

Oracle Training from Don Burleson 

The best on site "Oracle training classes" are just a phone call away! You can get personalized Oracle training by Donald Burleson, right at your shop!

Oracle training



Burleson is the American Team

Note: This Oracle documentation was created as a support and Oracle training reference for use by our DBA performance tuning consulting professionals.  Feel free to ask questions on our Oracle forum.

Verify experience! Anyone considering using the services of an Oracle support expert should independently investigate their credentials and experience, and not rely on advertisements and self-proclaimed expertise. All legitimate Oracle experts publish their Oracle qualifications.

Errata?  Oracle technology is changing and we strive to update our BC Oracle support information.  If you find an error or have a suggestion for improving our content, we would appreciate your feedback.  Just  e-mail:  

and include the URL for the page.


Burleson Consulting

The Oracle of Database Support

Oracle Performance Tuning

Remote DBA Services


Copyright © 1996 -  2020

All rights reserved by Burleson

Oracle ® is the registered trademark of Oracle Corporation.



Oracle Training at Sea
oracle dba poster

Follow us on Twitter 
Oracle performance tuning software 
Oracle Linux poster