Once the database has started, there are three ways to reconfigure the logging without having to stop and restart the database:
Call the @UpdateLogging system procedure passing the contents of the new configuration file as a text string.
Issue the voltadmin log4j command specifying the location of the new configuration file.
If you only want to change the logging level of one component of VoltDB, you can invoke the voltadmin log4j command specifying the name of the logger, an equals sign, and the new logging level. For example:
$ voltadmin log4j network=debug
When passing a configuration file by calling @UpdateLogging or voltadmin log4j, for any existing appenders included in the new configuration the previous configuration is removed and the new configuration applied. Other existing appenders (those not mentioned in the updated configuration file) remain unchanged. However, it is important to note that the changes triggered by @UpdateLogging and voltadmin log4j are only temporary and will be lost the next time the server process restarts. To persist any changes to the logging configuration, you must include them in a custom configuration file specified in the LOG4J_VOLTSERVER_PATH environment variable.
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