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Remote Desktop Services can be configured to deliver a HTML5 web client of the published applications. This may be desired over the RemoteApp solution.
hosts file
In order for the RDS VM to be able resolve DNS requests to itself using the FQDN, an entry should be added to the hosts file.
Edit the C:\Windows\System32\drivers\etc\hosts file to point the FQDN to 127.0.0.1
This will allow you to, say open a web browser and navigate to https://jiwards.jiwa.com.au and it be able to reach the locally running IIS instance for the web client.
This is not an essential configuration, but is sometimes useful.
Where this may be essential is if you are running the API self hosted service on the VM, have configured for HTTPS and wish to use the custom domain FQDN.
Secure the Remote Desktop Server
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Now that the Remote Desktop Gateway is configured, we only need to leave port 443 open (HTTPS) and port 80 (HTTP). The RemoteApp, Webclient and HTML5 client all require port 443 (HTTPS), and we also need port 80 open for the regular 3 monthly certificate renewal automatically performed by the win-acme client.
The rule in the Azure firewall for port 3389 to be open should be removed.
App Registration for Email through Office 365 (Microsoft Graph API)
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