Hi,
I have installed the ArcGIS for Server 10.3.1, ArcGIS Web Adaptor (Java Platform) 10.3.1, Portal for ArcGIS 10.3.1 and Oracle WebLogic 12c. All installations are on same machine. IIS is disabled on this machine and I have assigned the port 80 to http and 443 to SSL as the pre-requisite for Web Adaptor.

Also, I have deployed Web Adaptor on WebLogic.

If I try to access the Web Adaptor via https://localhost/arcgis/webadaptor or http://localhost/arcgis/webadaptor, I can able to see the configuration page (pasted the screen shot).

But, when I select Portal for ArcGIS option and click next it redirects to https://system_name_domain/arcgis/webadaptor/portal and shows a message "Configuration URL has to be accessed from the same machine as WebAdaptor" ( message screen shot is given below).
Again, if I try to access the same via system IP then too I get the same message ("Configuration URL has to be accessed from the same machine as WebAdaptor"). This is strange as I am trying to access the Web Adaptor from the same machine where all the software are installed (listed in first line) and it is happening on both http:// and https://


Here is the Web Adaptor deployment screen shot. If I click on the URLs, that also gives the same message

To remove suspicion on IP mapping, I have deployed a sample application and this can be accessible from localhost/application, system_name/application and IP/application. Checked on both http and https.
Please help me in setup of Portal for ArcGIS.
UPDATE: After a while, I tried the ArcGIS Web Adaptor 10.4 and this time I haven't faced any problem as version 10.3.1.
Thanks