The java options are set inside /etc/default/tomcat-instance-{{ item.0.http_port }}
The GHN environment variables are set inside /etc/default/tomcat-instance-{{ item.0.http_port }}.local

The commands that start and stop the containers are:
/home/gcube/startContainer.sh
/home/gcube/stopContainer.sh

The log files live inside /home/gcube/tomcat/logs (it's a symbolic link to {{ tomcat_m_instances_logdir_base }}/{{ item.0.http_port }})