# The error log

Once you create or connect to a database within a system, Derby begins outputting information and error messages to the error log.

Typically, Derby writes this information to a log called derby.log in the system directory, although you can also have Derby send messages to a stream, using the `derby.stream.error.method` property. By default, Derby overwrites derby.log when you start the system. You can configure Derby to append to the log with the `derby.infolog.append` property. For information on setting this and other properties, see Tuning Java DB.

Parent topic: Derby system
Related concepts
Booting databases
Recommended practices