CODEWITHSUNDEEP
javaloggingexceptionlog4j2
k0der
k0der

Reputation: 147

How to handle exceptions in logging when use Log4j2 Async logging?

In my application, I am using Log4j2 in Async mode (Async logger using Disruptor), can some one pls tell me how to handle an exception that happens in the logging process. Logging is very critical for my application, I don't want to miss a single log statement. If something goes wrong with logging, that needs to be alerted immediately.

As per Apache Log4j page, suggests to use ExceptionHandler, but I couldn't find a helping topic on how to use this.

Error handling. If a problem happens during the logging process and an exception is thrown, it is less easy for an asynchronous logger or appender to signal this problem to the application. This can partly be alleviated by configuring an ExceptionHandler, but this may still not cover all cases. For this reason, if logging is part of your business logic, for example if you are using Log4j as an audit logging framework, we would recommend to synchronously log those audit messages. (Note that you can still combine them and use asynchronous logging for debug/trace logging in addition to synchronous logging for the audit trail.)

Waiting for suggestions.

Upvotes: 1

Views: 1759

Answers (1)

Remko Popma
Remko Popma

Reputation: 36754

I suggest first trying to implement a simple class that implements the ExceptionHandler interface and confirm that it gets called when a problem occurs. Once this is confirmed you can move on to implementing your custom fallback mechanism.

Secondly, it may be difficult to develop a robust fallback: your fallback may not be able to write to disk if the reason why log4j failed was that the disk is full or damaged. Similarly you may not be able to make a network connection... I suggest that your fallback incorporates multiple options to increase the probability of one of these options succeeding.

Hardware is cheap, so consider adding a separate network card or a separate hard disk for your fallback mechanism. Don't forget to send notifications if the fallback mechanism is used so you can address the original problem.

Depending on how mission-critical this is you may want to investigate vendor products that give high availability - this usually covers more than just logging, not sure what your needs are here.

Upvotes: 2

Related Questions