Redirect domain.com to www.domain.com

The simplest way is you create an alias in your dns system to point domain.com to www.domain.com.

 

That is already in place, and works. What i need to do is when the request hits my BIG-IP i need to tack on the www. to the domain.com but only if it comes in as http://domain.com.

Or you can use an iRule:

 
 when HTTP_REQUEST { 
  
     Check if there was a host header value doesn't start with www. and does start with an alphabet character 
    if { not ([string match -nocase www.* [HTTP::host]]) && [string match -nocase a-z* [HTTP::host]]}{ 
  
       HTTP::redirect "http://www.[HTTP::host]" 
    } 
 } 
 

Or something more specific:

 
 when HTTP_REQUEST { 
  
     Check if the host header value isn't www.domain.com 
    if { not ([string tolower [HTTP::host]] eq "www.domain.com") }{ 
  
       HTTP::redirect "http://www.domain.com" 
    } 
 } 
 

Aaron

Thanks Aaron, this worked you are the man.

If they came into a specific url without the www prefix, would you just add the [HTTP::uri]?

If you rewrite the URI, the client wouldn't necessarily see the update to www.example.com and may end up making a request to https://example.com instead of https://www.example.com causing a cert mismatch error on the browser.

 

 

Aaron

Good point, I didn't think of that Aaron.

An alternative to the string match, though I'm not sure which is more optimal:

 
  when HTTP_REQUEST { 
      if { [HTTP::host] equals [domain [HTTP::host] 2] } { 
         HTTP::redirect "http://www.[HTTP::host]" 
      } 
   }