Converting log4j.properties file for Tomcat to work with Log4j2

Question

I\'m trying to configure Tomcat 8 to use Log4j2 for logging.

I\'ve found this reference for Logging in Tomcat using Log4j. It provides a sample log4j.properties file th

Answer 1

I followed the reference for Logging in Tomcat using Log4j and added tomcat-juli.jar to the bin dir and I also added tomcat-juli-adapters.jar to the lib dir. Afterwards i added the log4j-api-2.1.jar, log4j-core-2.1.jar and log4j-1.2-api-2.1.jar to the lib dir.

After that I added log4j2.xml to the lib dir. I kept the configuration fairly simple using a time and size based rolling configuration that zips the archived logs:

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="warn" name="catalina" packages="">

    <Appenders>
        <RollingRandomAccessFile name="catalina"
            fileName="${sys:catalina.base}/logs/catalina.log"
            filePattern="${sys:catalina.base}/logs/catalina/$${date:yyyy-MM}/catalina-%d{yyyy-MM-dd}-%i.log.zip">
            <PatternLayout>
                <Pattern>%d{MMM d, yyyy HH:mm:ss}: %5p (%F:%L) - %m%n</Pattern>
            </PatternLayout>
            <Policies>
                <TimeBasedTriggeringPolicy />
                <SizeBasedTriggeringPolicy size="250 MB" />
            </Policies>
            <DefaultRolloverStrategy max="100" />
        </RollingRandomAccessFile>
    </Appenders>
    <Loggers>
        <!-- default loglevel for emaxx code -->
        <logger name="org.apache.catalina" level="info">
            <appender-ref ref="catalina" />
        </logger>
        <Root level="info">
            <appender-ref ref="catalina" />
        </Root>
    </Loggers>
</Configuration>

This way you'll get all logging in the catalina.log. I'm still working on getting the accessLog to do the same.
EDIT: I found this site. this way you can direct access logging to the catalina.log. (I couldn't get it to log to it's own appender)

I didn't worry about the logging for manager and host manager, since we don't have them in production environments, but they might just log to the catalina.log too. I haven't tested it.

This was tested on tomcat-7.0.42, it should work in tomcat8 too.

Answer 2

After asking this question, I spent some more time with setting up log4j2, and this is the log4j2.xml file I came up with. It mimics the configuration described in Logging in Tomcat using Log4j. It uses multiple loggers to route messages to separate log files.

<?xml version="1.0" encoding="utf-8"?>
<Configuration status="info">
  <Properties>
    <Property name="logdir">${sys:catalina.base}/logs</Property>
    <Property name="layout">%d [%t] %-5p %c- %m%n</Property>
  </Properties>
  <Appenders>
    <Console name="CONSOLE" target="SYSTEM_OUT">
      <PatternLayout pattern="${layout}"/>
    </Console>
    <RollingFile name="CATALINA"
        fileName="${logdir}/catalina.log"
        filePattern="${logdir}/catalina.%d{yyyy-MM-dd}-%i.log">
      <PatternLayout pattern="${layout}"/>
      <Policies>
        <TimeBasedTriggeringPolicy />
        <SizeBasedTriggeringPolicy size="1 MB"/>
      </Policies>
      <DefaultRolloverStrategy max="10"/>
    </RollingFile>
    <RollingFile name="LOCALHOST"
        fileName="${logdir}/localhost.log"
        filePattern="${logdir}/localhost.%d{yyyy-MM-dd}-%i.log">
      <PatternLayout pattern="${layout}"/>
      <Policies>
        <TimeBasedTriggeringPolicy />
        <SizeBasedTriggeringPolicy size="1 MB"/>
      </Policies>
      <DefaultRolloverStrategy max="10"/>
    </RollingFile>
    <RollingFile name="MANAGER"
        fileName="${logdir}/manager.log"
        filePattern="${logdir}/manager.%d{yyyy-MM-dd}-%i.log">
      <PatternLayout pattern="${layout}"/>
      <Policies>
        <TimeBasedTriggeringPolicy />
        <SizeBasedTriggeringPolicy size="1 MB"/>
      </Policies>
      <DefaultRolloverStrategy max="10"/>
    </RollingFile>
    <RollingFile name="HOST-MANAGER"
        fileName="${logdir}/host-manager.log"
        filePattern="${logdir}/host-manager.%d{yyyy-MM-dd}-%i.log">
      <PatternLayout pattern="${layout}"/>
      <Policies>
        <TimeBasedTriggeringPolicy />
        <SizeBasedTriggeringPolicy size="1 MB"/>
      </Policies>
      <DefaultRolloverStrategy max="10"/>
    </RollingFile>
  </Appenders>
  <Loggers>
    <Root level="info">
      <AppenderRef ref="CATALINA"/>
    </Root>
    <Logger name="org.apache.catalina.core.ContainerBase.[Catalina].[localhost]"
        level="info" additivity="false">
      <AppenderRef ref="LOCALHOST"/>
    </Logger>
    <Logger name="org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/manager]"
        level="info" additivity="false">
      <AppenderRef ref="MANAGER"/>
    </Logger>
    <Logger name="org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/host-manager]"
        level="info" additivity="false">
      <AppenderRef ref="HOST-MANAGER"/>
    </Logger>
  </Loggers>
</Configuration>

However, getting this to work properly required getting a bunch of other files configured correctly. The tomcat 7 internal logging with log4j2.xml posting from Paramita Banerjee was helpful with this.

This file goes in CATALINA_HOME/bin/:

• tomcat-juli.jar

If you're pulling this from the Maven repository, you'll get a file named something like tomcat-extras-juli-8.0.15.jar (the current version when I wrote this). However, it needs to be renamed to tomcat-juli.jar – the Tomcat setup scripts use that name in setting up the CLASSPATH.

These files go in CATALINA_HOME/lib/:

• commons-logging-1.2.jar
• log4j-1.2-api-2.1.jar
• log4j-api-2.1.jar
• log4j-core-2.1.jar
• log4j-jcl-2.1.jar
• log4j-jul-2.1.jar
• log4j-web-2.1.jar
• tomcat-juli-adapters-8.0.15.jar

log4j-web-2.1.jar may not be needed here (it may just need to be deployed with your web application) – its use is described in Using Log4j 2 in Web Applications. log4j-1.2-api-2.1.jar is needed only if you have applications that use the older log4j 1.2 interface.

In CATALINA_BASE/conf, I disabled logging.properties.

I used the following setenv.sh script to define the CLASSPATH and LOGGING_MANAGER environment variables correctly for Tomcat. It goes in either CATALINA_BASE/bin or into CATALINA_HOME/bin. (I put it in CATALINA_HOME/bin.) It is executed by Tomcat's startup scripts if it's present. You might prefer something simpler, but this is in keeping with the style of the startup scripts.

LOG4J_JARS="log4j-core-2.1.jar log4j-api-2.1.jar log4j-jul-2.1.jar"

# make log4j2.xml available
if [ ! -z "$CLASSPATH" ] ; then CLASSPATH="$CLASSPATH": ; fi
CLASSPATH="$CLASSPATH""$CATALINA_BASE"/lib

# Add log4j2 jar files to CLASSPATH
for jar in $LOG4J_JARS ; do
  if [ -r "$CATALINA_HOME"/lib/"$jar" ] ; then
    CLASSPATH="$CLASSPATH":"$CATALINA_HOME"/lib/"$jar"
  else
    echo "Cannot find $CATALINA_HOME/lib/$jar"
    echo "This file is needed to properly configure log4j2 for this program"
    exit 1
  fi
done

# use the logging manager from log4j-jul
LOGGING_MANAGER="-Djava.util.logging.manager=org.apache.logging.log4j.jul.LogManager"

As Nick mentioned in his response, there's also the output to the access log. I haven't tried to do anything with that, either.

I hope others find this useful. In retrospect, it seems pretty straightforward. However, there are a lot of parts that have to be “just right” for it to work, and that was a challenge (at least for a newbie).

Answer 3

For system properties you need to prefix variables with "sys:" it indicates System Properties

Example:

appender.file.fileName=${sys:catalina.base}/logs/XXX.log

for more information go through below link http://logging.apache.org/log4j/2.x/manual/configuration.html#PropertySubstitution