EAP 5 fails to join mod_cluster balancer on httpd 2.4

Issue

• We're upgraded httpd to 2.4 and want to use that as a mod_cluster balancer for existing EAP 5 environments. EAP 5 is failing to join the balancer however. We note its MCMP requests are failing on httpd with a 400 and the following message:

AH00569: client sent HTTP/1.1 request without hostname (see RFC2616 section 14.23): /