Showing posts from June, 2020

Apache Karaf and log4j2 appenders

If Karaf default logging service matches most of users need, I had questions about how to add new or custom appenders. Karaf and Pax Logging The first thing to remember is that Apache Karaf doesn’t directly use log4j or slf4j or any direct logging framework. In order to provide maximum flexibility with unique configuration, Karaf uses Pax Logging. Pax Logging “abstracts” bunch of logging frameworks. The purpose is to allow the developer to use the logging framework he wants and the devops doesn’t care about the logging framework, he just know the “central” and unique pax-logging configuration, dealing with the concrete logging framework. This approach is very convenient and flexible, but he has a minor drawback: adding new “modules” (appenders, layout, etc) has to be done at Pax Logging level. Fortunately, it’s easy 😉 Pax Logging extra On Apache Karaf 4.2.x and 4.3.x, we are using pax-logging-log4j2 service implementation. Basically Pax Logging is splitted in two parts: Pax Logging AP