302 redirect string capture and replace

That should work okay. You could replace [HTTP::status] starts_with "3" with HTTP::is_redirect. Also, the Host header does not exist in responses, so you don't need to try to replace/insert it.

 
 when HTTP_REQUEST { 
     Replace the existing host header value with www.test.com 
    HTTP::header replace "Host" "www.test.com" 
 } 
 when HTTP_RESPONSE { 
  
     Check if response is a redirect 
    if { [HTTP::is_redirect]} { 
  
        Check if response contains the old domain name 
       if { [HTTP::header location] contains "http://www.redirect.com/" } { 
  
           Replace the old domain name with the new one in the Location header 
          HTTP::header replace location [string map {www.redirect.com www.test2.com} [HTTP::header location]] 
       } 
    } 
 } 
 

Aaron