How to set up distributed logging with Log4j2 and Kafka while avoiding message loss?
I'm currently trying to implement distributed logging using Log4j2 in a Spring Boot application, where the logs should be sent to a Kafka topic for further processing. However, I am working with issues with message loss, especially under high load conditions. I have configured my Log4j2 appender to send logs to Kafka, but when I run performance tests with a large number of log entries, I notice that not all messages are being sent to Kafka, and occasionally I see the following behavior in my logs: `behavior KafkaAppender - Failed to send message: TimeoutException: Failed to update metadata after 60000 ms.` Here’s a snippet of my `log4j2.xml` configuration: ```xml <Configuration status="WARN"> <Appenders> <Kafka name="KafkaAppender" topic="logs"> <Property name="bootstrap.servers">localhost:9092</Property> <JsonLayout /> <Producer> <Property name="acks">all</Property> <Property name="retries">3</Property> <Property name="linger.ms">5</Property> </Producer> </Kafka> </Appenders> <Loggers> <Root level="info"> <AppenderRef ref="KafkaAppender" /> </Root> </Loggers> </Configuration> ``` I am already using the latest version of Log4j2 (2.17.2) and Kafka (2.8.0). I have tried increasing the `linger.ms` to allow more time for batch sending, but it hasn’t resolved the scenario. Additionally, I am considering adjusting the Kafka producer's `buffer.memory` and `batch.size`, but I’m not sure what values would be appropriate. Could someone provide guidance on best practices for configuring Log4j2 with Kafka to minimize message loss and improve reliability, especially when under load? Any specific adjustments in the configuration or code that have worked for others would be greatly appreciated. Am I missing something obvious? I'm working on a REST API that needs to handle this. Am I missing something obvious?