Stealth Redirection or URL Hiding

Or perhaps something like this:

when HTTP_REQUEST {
    switch -glob [string tolower [HTTP::uri]] {
        "/news*"  {
            pool news.xxx.com-pool
            HTTP::uri [string map {"/news" "/"} [HTTP::uri]
        }
        default {
            pool www.abc.com-pool
        }
    }
}

If the URI starts with "/news", send to the news pool and strip the "/news" portion of the URI. You're still going to run into problems though. If the news host makes local references to content (images, links, JavaScript, style sheets, etc.) that don't start with "/news", your iRule won't know which direction to send the traffic when the client makes a request for that content. And since everything is going to the same host (www.abc.com), you might necessarily have to:

1. Ask the news host to put everything behind a "/news" URI structures - easy for you but difficult for them.

2. Rewrite all URI references that come from the news host to add the "/news" portion to the URI - easy for them but (a little) difficult for you.