Get HTTP::uri in HTTP_RESPONSE

Ah, so that error is because the HTTP::path command is not valid in the HTTP_RESPONSE event. There isn't a URI or path in responses.

If you want to retry the request to a new pool, you can use HTTP::retry. Here is a rough, untested example.

I'm assuming you are only concerned with GET requests. If you want to handle POSTs or other requests with a payload, you'd need to collect the payload on every request using HTTP::collect and then append the payload to the request headers in HTTP_REQUEST_DATA.

 
  Based on the example on the HTTP::request wiki page: 
  http://devcentral.f5.com/wiki/default.aspx/iRules/http__retry.html 
 when CLIENT_ACCEPTED { 
  
     Initialize a variable to track whether a request has been retried 
    set retries 0 
 } 
 when HTTP_REQUEST { 
  
     Check if request is a GET (we only save the request headers using HTTP::request) 
    if {[HTTP::method] eq "GET"}{ 
  
        Save the request headers 
       set request_headers [HTTP::request] 
       log local0. "HTTP request headers: $request_headers" 
    } 
 } 
 when LB_SELECTED { 
    if { $retries >= 1 } { 
      LB::reselect pool pool_b 
    } 
 } 
 when HTTP_RESPONSE { 
  
    if { [HTTP::status] == 404 } { 
       incr retries 
       log local0. "4xx error caught: retry $retries out of [active_members [LB::server pool]]" 
  
       if { $retries < [active_members [LB::server pool]] } { 
          HTTP::retry $request_headers 
       } 
    } else { 
        Successful response, reset the retries variable 
       set retries 0 
    } 
 } 
 

Aaron