Configure the
      log4j property group to control logging activities for each service running in
    your Hadoop cluster.
    Ambari uses sets of properties called log4j
        properties to control logging activities for each service running in your Hadoop
      cluster. Initially, default values for each property reside in
        Advanced[SERVICE_NAME]-log4j in a [SERVICE_NAME]-log4j
        template file, and in custom[SERVICE_NAME]-log4j in a
        custom[SERVICE_NAME]-log4j properties file. Log4j properties and values
      that limit the size and number of backup log files for each service appear in
        Advanced[SERVICE_NAME]-log4j with the log4j template file. Together,
      the log4j template, custom properties file and backup properties are called the log4j property
      group. To configure log settings for a service, first access the log4j property group for the
      service.
    - 
        In Ambari Web, browse to .
        For example, Advanced yarn-log4j in the YARN log4k property group for the YARN
          service looks like:  
- 
        In Ambari Web, browse to  and browse to custom [SERVICE_NAME]log4j
          properties.
      
Use the template and custom properties files for a selected
      service to edit and customize specific properties and values that control log activities for
      that service, as necessary.