Shortest version: that's not an OBI problem but something you handle - for example - in an Apache sitting in front of your obi.
Ref reverse proxy
Long version: your reverse proxy isn't fully configured apparently.
Publisher is on a different path, it's not on /analytics but /xmlpserver, you just don't see it as it is loaded into a frame of a /analytics page.
So configure all the paths OBIEE and related products use in your proxy and you must be fine (so if you have licenses for Visual Analyzer same thing as it's on a /va path).