Oracle Diagnostics Logging (ODL) (or better called Oracle Fusion Middleware Logging) is not shipped with the Oracle WebLogic Server software, but is part of an extension of additional installed Oracle Software such as the Oracle SOA Suite.

Although, as mentioned, it's not WebLogic logging, I'd like to mention it in a short overview because it's a very good extension on the already existing logging. Oracle Diagnostics Logging (or ODL) seeks to harmonize the different logging standards that have evolved among Oracle's products. The many differing standards make the management of several of Oracle's products a much more challenging task than is strictly necessary. As an administrator, you needed to learn and use several different methods. With ODL the log files can be managed in Enterprise Manager, centralizing the log file handling.

Log files and diagnostics can be shown within the Enterprise Manage Console. The developer can add the odl-handler into the code to make use of the ODL.

The administrator can, if Oracle Enterprise Manager is installed and added to the domain, view and search for ODL log files.