iRules and HTTP classes

Hi Craig,

 

 

Can you post the current iRule code you're trying to replace with HTTP classes?

 

 

For a standard HTTP VIP with an HTTP class, I'd expect the following events to be triggered:

 

 

CLIENT_ACCEPTED - TCP connection from client to VIP established

 

HTTP_REQUEST - client's HTTP request headers parsed

 

HTTP_CLASS_SELECTED (if a matching class is found for a request) or HTTP_CLASS_FAILED (if no matching class is found for a request)

 

LB_SELECTED - pool member selected

 

SERVER_CONNECTED - TCP connection from LTM to server established

 

HTTP_REQUEST_SEND - just before the HTTP request is sent to the server

 

HTTP_RESPONSE - server's HTTP response headers parsed

 

SERVER_CLOSED - LTM to server connection closed

 

CLIENT_CLOSED - client to VIP connection closed

 

 

There are probably a lot of exceptions/additions to this, but I think that list covers the basics.

 

 

For details on the events, you can check the wiki page:

 

 

http://devcentral.f5.com/wiki/default.aspx/iRules/events

 

 

Aaron

Hi Aaron,

 

 

Here's the code. At the moment it basically just checks for the status of the pool members to see if at least one of them is up and if so directs the traffic there. If no pool members are avaiable then it directs to an alternate pool whose members are responsible for displaying error page.

 

 

I will be changing the failed confition pool to a either a redirect or uri rewrite since they have created a new error message page within our web apoplication (WebSphere). Originally they intended to host it on a seperate IIS server.

 

 

  
   if { [string tolower [HTTP::uri]] contains "/new-services/" } {   
      if { [active_members "New-Services"] > 0 } {     
         pool "new-services"   
         return   
     } else {   
        pool "new-services-down"   
        return    
    }     
   }   
  

 

 

I just couldn't see how I could replicate this with HTTP classes.

 

 

Craig

Hi Craig,

 

 

You can't check the pool availability with an HTTP class, so you'll need to stick with the iRule for this one.

 

 

Aaron

Hi Aaron,

 

 

thanks for confirming this.

 

 

Craig