We need a note or an info box for EAP acting as an Undertow mod_cluster Proxy load balancer saying something along these lines:

The communication between EAP Undertow mod_cluster Proxy balancer and its EAP worker nodes is initialised from both directions: balancer contacts workers with requests and also workers actively contact the balancer with reports on their health and currently deployed applications. For this reason, it is paramount that you bind worker nodes on a concrete IP address accessible from within your virtual network, not on 0.0.0.0 and not on localhost. Workers then report this address of theirs to the balancer and the balancer must be able to contact them back on these reported addresses.

Book: https://access.qa.redhat.com/documentation/en/red-hat-jboss-enterprise-application-platform/7.0/single/using-jboss-eap-on-microsoft-azure/