For testing I often setup servers on a different port number. That way I don’t need to play with DNS and Host headers work.
I’m using a URL in the the standard form: http://host.domain.com:1234/uri
However, WebPageTest seems to break when testing against a non-standard port, reporting a ‘DNS lookup failed’.
Can this be fixed? It would make it easy to test and compare back-end server changes without affecting a live site.