Razor uses TorqueBox's logging subsystem exclusively for logging. Please read the TorqueBox documentation on logging for details about how to configure that.
Razor logs to a few different categories, which can be used to separate the wheat from the chaff in looking through logfiles:
razor.web.logserver access log in common log formatrazor.web.apiadditional messages from the API frontend, including details about errorsrazor.messaging.sequelmessages about the internal messaging used, for example, when importing ISO'srazoreverything else