Due do change in the proxy_balancer structure between 2.2.15 and 2.2.17 (which is the version used to compile EAP), a Segmentation Fault was thrown from mod_proxy_cluster.so when running more than one EAP server cluster behind a single Apache server. This was because all the clusters used the same domainname (usually the cluster name). This issue was resolved by reading the size of the proxy_balancer structure for the httpd mod_proxy tables and using that size in mod_cluster logic. The Segmentation Faults no longer present.