Load balance requires atleast two outgoing interfaces. In your case, I can see that there is only 1 interface defined Also, the incoming and outgoing are the same interface, hence I do need more info on your requirements as to what type of traffic is loadbalanced
Are the users and the servers in the same subnet? It seems like it given the policy you have created. This will make things more complicated as you'll have to try and do this using NAT trickery which I'm not 100% would work. The best solution would be to have your servers in a different subnet so you can do the load balancing the same way as you do it for external users (from one interface to another).
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