RAS Management Portal can run in any modern web browser supporting HTML5 except for Internet Explorer.
Make sure your Windows Server has the following updates installed (RAS Management Portal depends on them):
Windows Server 2012 R2: KB2999226
Newer versions of Windows Server do not require any specific updates.
The web service listens to web requests on the following ports by default:
HTTPS: 20443
HTTP: 20080
To enable RAS Management Portal in a RAS Farm, you need to install the RAS Web Administration Service component. The component is installed automatically when you do a clean Parallels RAS install using the "Typical" installation option. You can also install the component using the "Custom" installation option and choosing the "RAS Web Administration Service" as the component to install. For example, if you want to install RAS Management Portal on a dedicated machine, you should use the "Custom" installation option and select "RAS Web Administration Service" as a component to install.
After the RAS Web Administration Service is installed, you need to configure it. Specifically, you need to specify a RAS Farm that the RAS Management Portal will be used to manage, and you also need to configure a number of other parameters. For complete instructions, please see Configure RAS Web Administration Service.