LTM with Virtual Server with Pool Member listensing on different port Numbers

You could probably make your life a little easier by creating separate pools for each port service and then switching on that:

when HTTP_REQUEST {
    log local0. "request URI: [HTTP::uri]"
    switch -glob [string tolower [HTTP::uri]] {
        "*hypplanning*" {
            log local0. "going to hyp_pool"
            pool hyp_pool
        }
        "*drm*" {
            log local0. "going to drm_pool"
            pool drm_pool
        }
    }
}

This has the added benefit of allowing you to 1) scale out each service independently, and 2) assign individualized health monitors per pool. If you see traffic going to the DRM pool (or node) but you're getting a 404 or 405 response, that likely indicates something is wrong with the request. A 404 is a "file not found", so I'd look closely at the URI that you're sending in the request.