Node selection via URL parameters

Question

Hello everyone! I'm trying to do the following...&nbsp;
I would like to monitor individual parts of one of our applications by hitting each member within the F5 pool on a regular basis, and always with the same user (so we can trace in the logs). So what I was thinking of, was calling the application as follows:&nbsp;
www.myapplication.com/login.jsp?node=MNS1&nbsp;
with an iRule that would:&nbsp;
1. Read in the"node" parameter, and route traffic to a particular node based off of that parameter&nbsp;
2. Remove the parameter before passing on to the app&nbsp;
Is this doable? Is there something like this already out there? If not, are there particular docs that I should take a look at to help me out?&nbsp;
Thanks!&nbsp;

what_lies_bene1 · Answer

If you've not too many nodes this should do the trick (although I'm sure it can be improved);

when HTTP_REQUEST {
 if { [HTTP::uri] ! contains "MSN" } {
  pool x.x.x.x
  LB normally if URI doesn't contain MSN
 elseif { [HTTP::uri] ends_with "MSN1" } {
  node x.x.x.x port }
 elseif { [HTTP::uri] ends_with "MSN2" } {
    node x.x.x.x port }...and so on...
 else { return }
 }

luke_55733 · Answer

Thanks Steve! I'll give that a shot and get back to you. Much appreciate the quick reply.

what_lies_bene1 · Answer

You're welcome. I'm far from an iRule expert right now but it should work fine. Let me know either way.

hoolio · Answer

Here's another example: 
&nbsp;  
&nbsp; Select pool member based on HTTP query string parameter  
&nbsp; https://devcentral.f5.com/wiki/iRules.Select_pool_member_based_on_HTTP_query_string_parameter.ashx 
&nbsp;  
&nbsp; Aaron

nathe · Answer

All 
  
 I wonder if this will work? Not at my lab so can't check syntax. Don't be afraid anyone to come back and tell me if this is complete nonsense and won't work.  
  
 when HTTP_REQUEST {
   switch [findstr [HTTP::query] "node=" 5 ] {
      "MNS1" {
         HTTP::uri [string range [HTTP::uri] 0 end-10]
         node x.x.x.x port
       }
      "MNS2" {
         node y.y.y.y port
         HTTP::uri [string range [HTTP::uri] 0 end-10]
       }
       default {
       log local0. "No node= match"
       }
   }
}  
  
 Obviously don't know how many parameter values there are or what you want to happen if there's no match. 
  
 Here's hoping, 
 N

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Node selection via URL parameters

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