Administration URL Usage When Federating Using Load Balancer

[WilliamCraft]

One of my clients has an HA setup with 10.7.1 but without web adaptors.  Instead, they're using F5 load balancers to distribute requests.  I'd like to know, when federating a multi-machine site with Portal, which URL should I be using for the Administration URL?  In a single-machine site, it's obvious that you could simply use the machine name with port 6443 as the example suggests in the UI.  But with a multi-machine site, should I be using the same value as the Services URL or should I be placing a load balancer in front of the site and subsequently using that URL instead?  I don't believe I should be using one of the hosting machine names in this case.  In other words, if my Services URL is https://loadbalancer.domain.net/arcgis, should my Administration URL be https://loadbalancer.domain.net/arcgis or https://loadbalancer.domain.net:6443/arcgis?  One other way to ask this, I suppose, is should I be using the private or public load balancer for the Administration URL?  Please see my diagram and screenshot below which is intended to covey federation between the Portal and its hosting site.  Thanks in advance for your help.  

[JonathanQuinn · Accepted solution]

As long as the load balancer is checking the health of the backend machines, it doesn't matter if you use a standard or non-standard port. The Cloudformation templates use the same URL for both. If this environment was exposed to the internet, you could want to have an external and internal LB, but the concept would still apply; having the LB forward traffic on 443 or 6443 doesn't matter.

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