It looks like Connext 5.3.1 has several cascading methods for passing QoS settings.

• $NDDSHOME/resource/xml/NDDS_QOS_PROFILES.xml
• URL Groups in NDDS_QOS_PROFILES environment variable

• <working directory>/USER_QOS_PROFILES.xml

  <dds xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:noNamespaceSchemaLocation="http://community.rti.com/schema/5.3.1/rti_dds_qos_profiles.xsd" version="5.3.1">
      <!-- Qos Library -->
      <qos_library name="UserQosProfilesLibrary">
        <qos_profile name="rmw_qos_profile_system_default">
          <participant_factory_qos>
             <logging>
                <output_file>/tmp/dds_log.txt</output_file>
                <verbosity>ALL</verbosity>
                <print_format>TIMESTAMPED</print_format>
             </logging>
          </participant_factory_qos>
        </qos_profile>
      </qos_library>
  </dds>
  

But no matter where I place my rmw_qos_profile_system_default profile in xml, I can't seem to get the logger to logout to file; E.g. setting the verbosity to ALL and checking the target log file path for new entries.

https://community.rti.com/howto/useful-tools-debug-dds-issues
http://design.ros2.org/articles/qos.html#integration-with-existing-dds-deployments

I tried passing qos_profile_system_default from rclpy.qos to the qos_profile argument when using the create_subscription function. Am I missing a step in setting the QoS here?

demonodespy/demonodespy/topics/listener_qos.py