iRule Recipe 1: Single URL Explicit Redirect

HTTP::host

retrieves the value of the Host header, while the Request-Target path is part of the Request-Target in the HTTP Request Start-Line. Consider a request in your browser URL bar:

http://site.com/newpath

This would produce an HTTP Request message similar to the following (I omit a number of likely headers that aren't relevant to this example):

GET /newpath HTTP/1.1
Host: site.com

Notice that the path element (i.e.,

/newpath

) is in the Request-Line. To extract that, you should use

HTTP::path

. Thus, to match the URL above, you would do this:

when HTTP_REQUEST {
    switch [string tolower [HTTP::host]] {
        "site.com" -
        "www.site.com" {
            if { [HTTP::path] eq "/newpath" } {
                HTTP::respond 301 Location "https://www.site2.com/newpath"
            }
        }
    }
}

I use

switch

to reduce the number of evaluations of

HTTP::host

and

string tolower

, but this could also be written:

if { [string tolower [HTTP::host]] eq "site.com" or [string tolower [HTTP::host]] eq "www.site.com" } { ... }

Having said all of this, I strongly recommend that you consider using a Local Traffic Policy.