[SOLVED] Logging to separate file (log4j2)

[Dim (Angelos)]

@autoit

# Logger - Demo.log
log4j2.logger.org.eclipse.smarthome.model.script.Demo = DEBUG, Demo

# File appender - Demo.log
log4j2.appender.Demo=org.apache.log4j2.RollingFileAppender
log4j2.appender.Demo.layout=org.apache.log4j2.PatternLayout
log4j2.appender.Demo.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS} [%-5.5p] [%-36.36c] - %m%n
log4j2.appender.Demo.file=${openhab.logdir}/Demo.log log4j2.appender.Demo.append=true
log4j2.appender.Demo.maxFileSize=10MB
log4j2.appender.Demo.maxBackupIndex=10

It seems to me that this part is incomplete (some declarations are missing?)

Try:

### Custom Loggers ###
# Demo
log4j2.logger.Demo.name = org.eclipse.smarthome.model.script
log4j2.logger.Demo.level = DEBUG
log4j2.logger.Demo.additivity = false
log4j2.logger.Demo.appenderRefs = Demo
log4j2.logger.Demo.appenderRef.Demo.ref = Demo

### Custom Appenders ###
# Demo
log4j2.appender.Demo.name = Demo
log4j2.appender.Demo.type = RollingRandomAccessFile
log4j2.appender.Demo.fileName = /var/log/openhab2/Demo.log
log4j2.appender.Demo.filePattern = /var/log/openhab2/Demo.log.%i
log4j2.appender.Demo.immediateFlush = true
log4j2.appender.Demo.append = true
log4j2.appender.Demo.layout.type = PatternLayout
log4j2.appender.Demo.layout.pattern = %d{yyyy-MM-dd HH:mm:ss.SSS} [%-5.5p] [%-36.36c] - %m%n
log4j2.appender.Demo.policies.type = Policies
log4j2.appender.Demo.policies.size.type = SizeBasedTriggeringPolicy
log4j2.appender.Demo.policies.size.size = 10MB
log4j2.appender.Demo.strategy.type = DefaultRolloverStrategy
log4j2.appender.Demo.strategy.max = 10

check: Log4j2 Sample Config - #39 by RobertOnOHCommunity also

Ps: Don’t use the example from https://docs.openhab.org/administration/logging.html#logging-into-separate-file since this is for log4j1 (not 2 that you are using)