Working at command line Linux with ArcGIS Enterprise 10.5.1, I just configured Web Adaptor using configurewebadaptor.sh and now the web adaptor arcgis/home page shows
Could not access any Portal machines. Please contact your system administrator.
Checking catalina.out log file shows this error repeatedly:
Jul 12, 2017 6:23:42 PM com.esri.arcgis.server.wa.cluster.UpdatePortalCacheTask updateMachinesList
WARNING: Exception in connecting to http://PORTAL.ARCGIS.NET:7080/arcgis/portaladmin Error in Portal Admin request for get machinesError in admin request for get machines PORTAL.ARCGIS.NET
The command I use to configure looks like this:
and in completes with the message "Successfully Registered." (Of course USER and PASS are defined elsewhere)
Note that the names for both web-adaptor and portal resolve correctly, and that from my desktop I can browse to the portal directly using the URL in the error message and when I click on Machines I see this:
Portal Health Check for PORTAL.ARCGIS.NET
Health Check successful, the portal is ready
In fact I use curl in a script before running configurewebadaptor.sh to make sure that both web-adaptor and portal are available on the URL's that I pass in.
I will try to write a test script to access the API from the web-adaptor machine to see what result that gives.