How is the -Dlogging.configuration set in EAP 6?

Issue

• I am starting up jboss6 using domain.sh in a managed domain mode and noticed one of the parameters on a given server node is:

-Dlogging.configuration=file:/usr/local/logs/node1/data/logging.properties

I have already set -Djboss.domain.servers.dir=/usr/local/logs so as to specify the directory under which a host controller will create the working area for individual server instances in a managed domain. How is the above mentioned system property "-Dlogging.configuration" being set/configured as I am not setting this as a startup parameter.