In every environment where the WebContextURL is set and the ArcGIS Server Port (underlying Server used by GeoEvent Server) is not accessible from outside or where the Webadaptor is installed on a different host than the ArcGIS Server (+GeoEvent) we are still having the following Error in the ArcGIS GeoEvent Server 10.8.1
Second attempt failed. Giving up. (https://webadaptor-host.fqdn:6443/arcgis/help/en/geoevent --- Connect to webadaptor-host.fqdn:6443 [webadaptor-host.fqdn /xxx.xxxx.xxx.xxx] failed: Connection timed out: connect)
GeoEvent is always mixing up the hostname that is configured @ WebContextURL with the default ArcGIS Server port and the default location of the help page. In this case we getting a lot of error messages from the HTTP Client that is trying to access the help page.
This page is available under: https://geoevent.fqdn:6443/arcgis/help/en/geoevent (but still this page is not accessible from outside)
GeoEvent is trying to access: https://webadaptor-host.fqdn:6443/arcgis/help/en/geoevent (this is just the webadaptor, there is not ArcGIS Server installed, so nothing will respond on that port)
Correct would be to access: https://webadaptor-host.fqdn/geoevent/help/en/geoevent (“geoevent” is the configured webadaptor, and the page is available here)