# Property Configuration

Control of log4j occurs based on properties typically set in the `log4j.properties` file in the application classpath. You can change the log level of a given logger in this file. Note, however, that values may be overridden on the command line by specifying system properties (for example, via `-Dlog4j..`.). Note that inheritance of logger levels works such that (in our standard of qualified class name as the logger name) you can change a whole package's log level by specifying only a portion of the logger name. Note that you may commonly desire to enable global debug logging on your local environment. To do this, you can simply change the line:

    			 logger.spl.level=info

to

    			 logger.spl.level=debug

Note: Changing the log is not recommended.
Parent topic: Configuring Logging at Runtime