I am currently putting together a number of Ansible roles for spinning up and ArcGIS Enterprise environment and I've just got to Federation. I am using the the rest interface (https://developers.arcgis.com/rest/enterprise-administration/portal/federation.htm) with the ansible module win_uri.
However when running through the request I a very similar error to what is discussed here: https://community.esri.com/thread/199488-registering-server-with-portal-prior-to-federation my reason for posting here is if I login to either the server or portal vm and try to federate using the web interface (/portaladmin/federation/servers/federate) I have no issues as i can access all URLs from either machine.
I am wondering if there is some blocker that may be causing communications issues with ansible? it seems really odd that I can do it via the web interface but not via ansible, i've tried running the playbook on both vms.