It occurs to me that there are communication problems between the two hosts,
WildFly uses JGroups which uses UDP multicast to do node discovery. Can you verify from the logs that the cluster formed and that UDP multicasting is working?
And another strange situation is that mod_cluster 1.3.1 see all nodes, but are all in load 0.
What OS are you running? Any chance you are hitting [WFLY-5890] Default mod_cluster load metric cpu (AverageSystemLoadMetric) is not supported on Windows - JBoss Issue Trac… ?
Put your apache in debug to see what port he is trying to connect. Use debug on mod_cluster to see port it will show on error.log
I got this problem here and he say 8009 but use 14126, then i change 8009 to 14126 or change install haproxy and make a proxy from 14126 to 8009
And the 0 load come to 100.