Hi William, Thanks for your inquiry about GeoEvent high availability. There is a wealth of information about the concepts and implementation steps for a multiple-machine site approach to high availability in the following tutorial: GeoEvent Server 10.6.x Multiple-Machine Site. Note: the tutorial is labeled as 10.6.x but applies to later versions as well. This tutorial answers many of your questions in detail, but I've addressed them directly below: Would it make sense to create a multi-node ArcGIS Server site and configure GeoEvent Server the exact same way on all of them? Will the GeoEvent Gateway properly handle the traffic between nodes in this case? Yes, GeoEvent Server supports multi-machine sites since ArcGIS Server 10.6.1. In this configuration, the GeoEvent Gateway acts as a distributed configuration store and message broker for all the machines in the site. The minimum recommended number of machines is three, to provide the best consistency in event of a single machine's failure. Could I then federate that entire site of GeoEvent Servers with the Portal and still see expected behavior? Yes, you could federate the site with Portal to take advantage of the Portal security/SSO, though it is not required. If I take this approach, will I see two sets of services (one from each GeoEvent Server) within my Portal once I publish a service from GeoEvent Server? No. Stream services will only run on a single machine in the GeoEvent site (see "Other considerations regarding GeoEvent Server multiple-machine sites" in the tutorial). Other services, i.e., hosted feature services or federated services, should be published to the hosting server. Feel free to reach out to me if you have additional questions. Regards, Brad Esri Professional Services
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