I tried to run my project on the latest Java 11. Everything works, except the specific file logger. Logging works fine on previous Java versions - 10, 9, 8, but not on Java 11.
During server run I see only 1 warning:
WARNING: sun.reflect.Reflection.getCallerClass is not supported. This will impact performance.
Here is my configuration:
<Configuration>
    <Appenders>
        <RollingFile name="postgresDBLog" fileName="${sys:logs.folder}/postgres.log"
              filePattern="${sys:logs.folder}/archive/postgres.log.%d{yyyy-MM-dd}">
            <PatternLayout>
                <pattern>%d{HH:mm:ss.SSS} - %msg%n</pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy/>
            </Policies>
        </RollingFile>
        <RollingFile name="workersLog" fileName="${sys:logs.folder}/worker.log"
                     filePattern="${sys:logs.folder}/archive/worker.log.%d{yyyy-MM-dd}">
            <PatternLayout>
                <pattern>%d{HH:mm:ss.SSS} - %msg%n</pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy/>
            </Policies>
        </RollingFile>
        <RollingFile name="statsLog" fileName="${sys:logs.folder}/stats.log"
                     filePattern="${sys:logs.folder}/archive/stats.log.%d{yyyy-MM-dd}">
            <PatternLayout>
                <pattern>%msg%n</pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy/>
            </Policies>
        </RollingFile>
        <RollingFile name="userLog" fileName="${sys:logs.folder}/blynk.log"
                     filePattern="${sys:logs.folder}/archive/blynk.log.%d{yyyy-MM-dd}">
            <PatternLayout>
                <pattern>%d{HH:mm:ss.SSS} %-5level- %msg%n</pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy/>
            </Policies>
        </RollingFile>
    </Appenders>
    <Loggers>
        <Logger name="cc.blynk.server.workers" level="debug" additivity="false">
            <appender-ref ref="workersLog"/>
        </Logger>
        <Logger name="cc.blynk.server.workers.StatsWorker" level="debug" additivity="false">
            <appender-ref ref="statsLog"/>
        </Logger>
        <Logger name="cc.blynk.server.db" level="debug" additivity="false">
            <appender-ref ref="postgresDBLog"/>
        </Logger>
        <Logger name="com.zaxxer.hikari" level="OFF" additivity="false">
        </Logger>
        <Logger name="org.asynchttpclient.netty.channel" level="OFF" additivity="false" />
        <!-- turn off netty errors in debug mode for native library loading
         https://github.com/blynkkk/blynk-server/issues/751 -->
        <Logger name="io.netty" level="INFO" additivity="false" />
        <Root>
            <AppenderRef ref="userLog"/>
        </Root>
    </Loggers>
</Configuration>
All loggers, except userLog works fine. However, userLog is empty.
log4j2 version 2.11.1
Ubuntu 16.04.5 LTS
java version "11.0.1" 2018-10-16 LTS
Java(TM) SE Runtime Environment 18.9 (build 11.0.1+13-LTS)
Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11.0.1+13-LTS, mixed mode)
Update:
Adding level="info" to the root level fixes the issue.
    <Root level="info">
        <AppenderRef ref="userLog"/>
    </Root>
However, in my project I was using a code that was setting a log level based on properties file. Here is a code:
private static void changeLogLevel(String level) {
    Level newLevel = Level.valueOf(level);
    LoggerContext ctx = (LoggerContext) LogManager.getContext(false);
    Configuration conf = ctx.getConfiguration();
    conf.getLoggerConfig(LogManager.ROOT_LOGGER_NAME).setLevel(newLevel);
    ctx.updateLoggers(conf);
}
Seems like this part is no longer work with Java 11.
 
     
     
     
     
     
    