"AsyncAppender is not active" when logging with AsynAppender while the system is reconfigure concurrently

2020-09-08 01:16:06,145 main ERROR An exception occurred processing Appender async-console java.lang.IllegalStateException: AsyncAppender async-console is not active2020-09-08 01:16:06,145 main ERROR An exception occurred processing Appender async-console java.lang.IllegalStateException: AsyncAppender async-console is not active at org.apache.logging.log4j.core.appender.AsyncAppender.append(AsyncAppender.java:168) at org.apache.logging.log4j.core.config.AppenderControl.tryCallAppender(AppenderControl.java:156) at org.apache.logging.log4j.core.config.AppenderControl.callAppender0(AppenderControl.java:129) at org.apache.logging.log4j.core.config.AppenderControl.callAppenderPreventRecursion(AppenderControl.java:120) at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:84) at org.apache.logging.log4j.core.config.LoggerConfig.callAppenders(LoggerConfig.java:508) at org.apache.logging.log4j.core.config.LoggerConfig.processLogEvent(LoggerConfig.java:468) at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:451) at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:426) at org.apache.logging.log4j.core.config.AwaitCompletionReliabilityStrategy.log(AwaitCompletionReliabilityStrategy.java:82) at org.apache.logging.log4j.core.Logger.log(Logger.java:158) at org.apache.logging.log4j.spi.AbstractLogger.tryLogMessage(AbstractLogger.java:2135) at org.apache.logging.log4j.spi.AbstractLogger.logMessageTrackRecursion(AbstractLogger.java:2089) at org.apache.logging.log4j.spi.AbstractLogger.logMessageSafely(AbstractLogger.java:2072) at org.apache.logging.log4j.spi.AbstractLogger.logMessage(AbstractLogger.java:1948) at org.apache.logging.log4j.spi.AbstractLogger.logIfEnabled(AbstractLogger.java:1920) at org.apache.logging.log4j.spi.AbstractLogger.info(AbstractLogger.java:1257) at ReconfigureTest.testLoggingWhenReconfigure(ReconfigureTest.java:27) at 

@Override
public void append(final LogEvent logEvent) {
    // ---------sleep to wait reconfigre() stop this appender----
    try {
        System.out.println("AsyncAppender append, sleep 10s");
        Thread.sleep(10000);
        System.out.println("AsyncAppender append, awake");
    }catch (InterruptedException e){
        e.printStackTrace();
    }
    // ----------------------------------------------------------

    if (!isStarted()) {
        throw new IllegalStateException("AsyncAppender " + getName() + " is not active");
    }
    final Log4jLogEvent memento = Log4jLogEvent.createMemento(logEvent, includeLocation);
    InternalAsyncUtil.makeMessageImmutable(logEvent.getMessage());
    if (!transfer(memento)) {
        if (blocking) {
            if (AbstractLogger.getRecursionDepth() > 1) { // LOG4J2-1518, LOG4J2-2031
                // If queue is full AND we are in a recursive call, call appender directly to prevent deadlock
                AsyncQueueFullMessageUtil.logWarningToStatusLogger();
                logMessageInCurrentThread(logEvent);
            } else {
                // delegate to the event router (which may discard, enqueue and block, or log in current thread)
                final EventRoute route = asyncQueueFullPolicy.getRoute(thread.getId(), memento.getLevel());
                route.logMessage(this, memento);
            }
        } else {
            error("Appender " + getName() + " is unable to write primary appenders. queue is full");
            logToErrorAppenderIfNecessary(false, memento);
        }
    }
}

// unit test
@Test
public void testLoggingWhenReconfigure(){
    Logger logger = LogManager.getLogger("logger");

    new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                // make logger.info execute first
                Thread.sleep(2000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("reconfiguring ...");
            LoggerContext.getContext(false).reconfigure();
            System.out.println("reconfiguring done...");
        }
    }).start();

    logger.info("info");
}

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="ERROR">
    <Appenders>
        <Console name="console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n" />
        </Console>
        <Async name="async-console">
            <AppenderRef ref="console"/>
        </Async>
    </Appenders>
    <Loggers>
        <logger name="logger" level="info" additivity="false">
            <AppenderRef ref="async-console" />
        </logger>
    </Loggers>
</Configuration>