Shulou(Shulou.com)06/01 Report--

APPLIES TO:

Oracle Database-Enterprise Edition-Version 10.2.0.5 and laterInformation in this document applies to any platform.

CAUSE

A hang is possible in earlier versions of RDBMS as a result of an unpublished bug fixed in the following versions: 12.1.0.1 (Base Release) 11.2.0.2 (Server Patch Set) 11.1.0.7 Patch 42 on Windows PlatformsDocument 9776608.8 Bug 9776608-Hang from concurrent login to same account with a wrong passwordEven with this fix, numerous failed logins attempts can cause row cache lock waits and/or library cache lock waits. This was reported in:Bug 11742803 LOTS OF 'LIBRARY CACHE LOCK' DURING USER LOGON AUTHENTICATIONThis was closed as not a bug because there is an intentional wait when a login fails.SOLUTIONIn Oracle 11g Release 11.1.0.7, the wait is disabled unconditionallyIn Oracle 11g Release 2 and higher, in order to disable the wait between login failures the event 28401 needs to be explicitly enabled:The event can be set as follows:alter system set event= "28401 TRACE NAME CONTEXT FOREVER, LEVEL 1" scope=spfile;To unset the event, set as follows:SQL > Alter system set event=' 28401 trace name context off' scope=spfile

Summary:

About a large number of concurrent incorrect passwords connecting to the database may cause database hang, or cause performance problems, which have a great impact on the database, such a case has been encountered recently. Of course, Oracle itself is a very good feature, but you do encounter some problems at the moment, you can use event 28401 to disable this feature. But it is best to solve such problems from the management and do a good job of management and control from the security level.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.