I’m in the middle of a prototype migration/deployment and have really hit a wall serving up my layers from geoserver. I’ve geoserver running from the “stand-alone” version running in jetty on one port and the webapp running in tomcat on another port. The webapp requests data from geoserver via localhost. This setup works fine on my laptop where I initially developed the prototype. Since moving everything to a server on the intranet, the webapp can request layers from geoserver, geoserver handles the request, and the webapp never gets anything returned. What’s even stranger, is if the prototype’s code is run a other hosts and requests data from the aforementioned geoserver, it gets data just fine. The webapp can successfully access remote WMS layers directly (not from, or cascaded by, my geoserver).
The laptop is running geoserver 2.3.0 and tomcat 7, both from an openSuSE 13.2 rpms, and Oracle's java 1.7.0_79. The server is running geoserver 2.7.2 (downloaded), and tomcat 7 and OpenJDK 1.7.0_85 from CentOS 7 rpms.