HOW TO
A GIS Server site can be registered as a hosting server once a federated GIS Server site has a relational and tile cache data store. Sometimes, a federated GIS Server site cannot be selected as the hosting server from the portal website for several reasons. One of which is configuring ArcGIS Web Adaptor to use a domain naming system (DNS) as opposed to a fully qualified domain name (FQDN).
As an alternative, follow the steps described in this article to specify the federated GIS server as the portal's hosting server through the ArcGIS Portal Directory REST endpoint.
Note: The following steps must only be performed by the organization administrator.
https://<webadaptorhost>.<domain>.com/<webadaptorname>/sharing/rest
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