F5 Reverse Proxy

Hello, we have an public host for example outlook.foo.bar.de/owa with a vaild certificate, the cert should hold the VIP and than we would like to access the internal backend system they provide outlook.test.local/owa, access has to be work without any certificate issues and the host should not change in the browser, the user should think he is on outlook.foo.bar.de/owa ! So I think we need in the client ssl profile the cert for outlook.foo.bar.de and in the server ssl profile the outlook.test.local correct ? But I think I need for that an iRule to change the host header, to mask the host in the browser and so on ? Is there a example iRule for such a scenario? 

kind regards