The Log Server is used to consolidate logging from all the other parts of the PortalProtect. Every component uses SLF4J to log all errors and debug statements, and SLF4J is implemented by either Logback or Log4h - both can be configured to forward log events to the Log Server.
The administration interface within the configuration / statistics server can be used to view the last 1000 items logged, the rest is written to a log file, or logged by other means, using a logback/log4j appender. See the section on logging, and the configuration section for details on how to setup logging to other destinations, like databases, NT eventlog or others.