http::host is not populated

The host is a value the client should set (optional in HTTP 1.0, required in HTTP 1.1) to indicate which web application on the web server it is making a request to. The idea was to allow servers to support multiple web applications without needing a separate IP address and port per web app. So yes, the client is supposed to tell the server which host it's making the request to. I would guess that you're web server is setting the HTTP_HOST CGI variable to the default HTTP host on the server if the client doesn't specify a host. Most clients (ie, all modern browsers) will specify the fully qualified domain in the address bar for a request in the HTTP host header, so this shouldn't really be an issue in most cases.

 

 

There isn't a simple way to determine what the default host of the web server is from an iRule on the BIG-IP. If you're opposed to using the VIP's IP address in the redirect, your next best option would probably be to hard code the host to use in a redirect if the client doesn't specify it in their request.

 

 

Aaron