The Portal Administrative Directory, referred to as Portal Admin here, is what the ArcGIS Server REST Admin is to ArcGIS Server--an interface to all administrative settings for Portal for ArcGIS. As with the Portal web interface, Portal Admin can be accessed from within the internal network (bypassing the Web Adaptor) at a URL such as this:
https://<FQDN>:7443/arcgis/portaladmin/
In our case, it would be as follows:
https://win-25fpfgemua9:7443/arcgis/portaladmin/
If administrative access is enabled on the Portal Web Adaptor, then we can access Portal Admin outside of our internal network at a URL such as this:
https://<FQDN>/webadaptor/portaladmin/
In our case, it would be as follows:
