Separating Log4J application logging from the server.log in JBoss EAP

Resolution

There are several steps involved in this, and it's important that each step is followed correctly, or this will not work. The high level steps are::

• Package a copy of log4j.jar in your deployment
• Add the system property -Dorg.jboss.as.logging.per-deployment=false 'Ref'
• Create a jboss-deployment-structure.xml to exclude org.apache.log4j from your deployment and all subdeployments.
• Explicitly initialize your Log4J configuration using a PropertyConfigurator or DOMConfigurator in your application.

Package log4j.jar in your application along with your Log4J configuration file (log4j.xml / log4j.properties) in the classpath (which would be in the root of a jar or in /WEB-INF/classes for a war).

Remember, "all subdeployments" means that if you have an EAR that there should be a jboss-deployment-structure.xml at the EAR level, and then another one inside of each WAR or any other type of nested deployment you have inside of that EAR.

Add the system property -Dorg.jboss.as.logging.per-deployment=false, which disables the deployer which scans for the logging configuration files in your deployment. This will prevent JBoss from trying to create a log context for your deployment.

If your logging configuration file has a different name than the standard ones (e.g. log4j.xml, log4j.properties), you will then need to initialize your logging framework in your code e.g. a ServletContextInitialzer if you're using a WAR:

import java.io.IOException;
import java.net.URL;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletContextEvent;
import org.apache.log4j.xml.DOMConfigurator;

@javax.servlet.annotation.WebListener
public class TestListener implements ServletContextListener {
  public void contextInitialized(ServletContextEvent event) {
    URL log4jXml = Thread.currentThread().getContextClassLoader().getResource("/my-log4j.xml");
    if(log4jXml == null)
      throw new IllegalStateException("my-log4j.xml not found");
    DOMConfigurator.configure(log4jXml);
  }
  public void contextDestroyed(ServletContextEvent event) {
  }
}

You will also need to declare an exclusion (as shown below) in order to not use the logging frameworks already provided by JBoss. Create a jboss-deployment-structure.xml in the root of your top level deployment in WEB-INF for wars or META-INF for all other types. Here is an example of what you'd put in the META-INF folder of an EAR:

<jboss-deployment-structure>
  <deployment>
    <exclusions>
      <module name="org.apache.log4j" />
    </exclusions>
  </deployment>
  <sub-deployment name="myapp.war">
    <exclusions>
      <module name="org.apache.log4j" />
    </exclusions>
  </sub-deployment>
</jboss-deployment-structure>

The same file would be put in the WEB-INF folder of a WAR without the <sub-deployment> element. Note that if you have multiple WARs embedded in an EAR, you must configure <sub-deployment/> for each WAR. You can not use a wildcard "*" for it. See Knowledge article #179153

A working example is attached as separate-logfile-example.zip. Extract the archive and follow the instructions described in README.txt. This sample application is based on ejb-in-ear quickstart project.

To create a separate log file for each server instance running in domain mode we can use jboss.node.name in log4j.xml/log4j.properties file, and while starting server instance use -Djboss.node.name=Node_Name property.

log4j.appender.myFileAppender.File=/valid/path/${jboss.node.name}.log 

<param name="File" value="${jboss.server.log.dir}/${jboss.node.name}.log"/>