Simple use case: one server IdP + one server SP

I try to make a simple test with one server holding the role of IdP for country A, and an other Boeing the SP country B. My concerns are about the configuration of each server. Basically I used the tomcat configuration and change localhost:8080 to countryA.spopoff.com:8080 for SP and countryB.spopoff.com:8080 for IdP. With that configuration the IdP failed to processus request from SP. It's online you van try. Any help? Best regards