I am trying to setup a standalone aeron archive media driver. This will be used by my publisher clients as well as subscribers. I intend to have two directional publish/subscribe agents per process that will connect to aeron.

While, setting up the mediadriver, if I let the mediadriver choose default directory (note: I am running locally on mac). It works fine. I am able to specify archive directory and that works.

Here is the code that works:

    public void init() {
        final String controlChannel = AERON_UDP_ENDPOINT + config.getHost() + ":" + config.getControlPort();
        final String replicationChannel = AERON_UDP_ENDPOINT + config.getHost() + ":" + config.getReplicationPort();
        final String recordingEventsChannel =
                "aeron:udp?control-mode=dynamic|control=" + config.getHost() + ":" + config.getEventsPort();

        LOGGER.info("Starting MediaDriver with control channel: {}, replication channel: {}, recording events channel: {}",
                controlChannel, replicationChannel, recordingEventsChannel);

        final var archiveContext = new Archive.Context()
                .deleteArchiveOnStart(true)
                .errorHandler(ArchieveMediaDriverService::errorHandler)
                .controlChannel(controlChannel)
                .replicationChannel(replicationChannel)
                .recordingEventsChannel(recordingEventsChannel)
                .idleStrategySupplier(SleepingMillisIdleStrategy::new)
                .threadingMode(ArchiveThreadingMode.SHARED)
                .archiveDir(new File(config.getAeronDirectoryName()));

        final var mediaDriverContext = new MediaDriver.Context()
                .spiesSimulateConnection(true)
                .errorHandler(ArchieveMediaDriverService::errorHandler)
                .threadingMode(ThreadingMode.SHARED)
                .sharedIdleStrategy(new SleepingMillisIdleStrategy())
                .dirDeleteOnStart(true);

        ArchivingMediaDriver.launch(mediaDriverContext, archiveContext);
        LOGGER.info("Media driver is ready.");

        aeron = Aeron.connect();
        LOGGER.info("Connected to Aeron {}", aeron.context());

        // Connect to AeronArchive
        aeronArchive = AeronArchive.connect(
                new AeronArchive.Context()
                        .aeron(aeron)
                        .controlRequestChannel(controlChannel)
                        .controlResponseChannel(replicationChannel)
        );
        LOGGER.info("MediaDriver is up and running");

        // Keep the MediaDriver running until the application is stopped
        Runtime.getRuntime().addShutdownHook(new Thread(this::stop));
    }

But if we set the directory to the same one as aeron archive directory, it gives a FATAL error saying cannot create CnC file.

        final var mediaDriverContext = new MediaDriver.Context()
                .spiesSimulateConnection(true)
                .aeronDirectoryName(config.getAeronDirectoryName())
                .errorHandler(ArchieveMediaDriverService::errorHandler)
                .threadingMode(ThreadingMode.SHARED)
                .sharedIdleStrategy(new SleepingMillisIdleStrategy())
                .dirDeleteOnStart(true);

The driver would timeout giving error:
Caused by: io.aeron.exceptions.DriverTimeoutException: FATAL – CnC file not created: /Users/user/dev/optradex/optradex-engine/resources/archiveDataFolder/cnc.dat

However, if I change the directory to a different directory than the archive folder, it works. But there is a FATAL error. It turns out to be a warning as the system works.

Here is the exception:

Caused by: io.aeron.exceptions.DriverTimeoutException: FATAL - no driver heartbeat detected
    at io.aeron.Aeron$Context.connectToDriver(Aeron.java:1563) ~[aeron-all-1.37.0.jar:1.37.0]
    at io.aeron.Aeron$Context.conclude(Aeron.java:790) ~[aeron-all-1.37.0.jar:1.37.0]
    at io.aeron.Aeron.<init>(Aeron.java:83) ~[aeron-all-1.37.0.jar:1.37.0]
    at io.aeron.Aeron.connect(Aeron.java:139) ~[aeron-all-1.37.0.jar:1.37.0]
    at io.aeron.Aeron.connect(Aeron.java:121) ~[aeron-all-1.37.0.jar:1.37.0]
    at com.xac.archivemediadriver.service.ArchieveMediaDriverService.init(ArchieveMediaDriverService.java:71) ~[main/:na]
    at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na]
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMethod.invoke(InitDestroyAnnotationBeanPostProcessor.java:457) ~[spring-beans-6.0.17.jar:6.0.17]
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:401) ~[spring-beans-6.0.17.jar:6.0.17]
    at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:219) ~[spring-beans-6.0.17.jar:6.0.17]
    ... 17 common frames omitted

I am trying to configure the archive directory as well as the mediadriver cnc file directory. Normally, mediadriver allows me when it is not an archive instance. I am assuming I am missing some documentation here. Hence raising this question.