Headwind MDM server settings are in the Tomcat XML file, which is usually located here: /var/lib/tomcat8/conf/Catalina/localhost/ROOT.xml (or .../hmdm.xml).
The following settings are related to the MDM server address:
base.url - this parameter is used when Headwind MDM forms URLs to the mobile agent.
mqtt.server.uri - here you specify the address on which Headwind MDM accepts incoming MQTT connections. Note that if your server is behind a firewall, you need to specify local IP instead of the external address here, see details: https://qa.h-mdm.com/1714/
We recommend to use a domain name instead of an IP address.