How to install XRDP on Ubuntu?

Introduction

xrdp is a Remote Desktop Protocol (RDP) Server, allowing RDP clients to be presented an X windows desktop to the user.

Installation

Simple setup with no user logged into console

This is a simple setup without using TLS and certificates. Also, it requires that no person is logged into the console when attempting to connect.

With Ubuntu 18.04 first install xrdp:

sudo apt-get -y install xrdp

Next, one may adjust the configuration file:

sudo nano /etc/xrdp/xrdp.ini

Set encryption level to high:

encrypt_level=high

Next, allow just RDP through the local firewall:

sudo ufw allow 3389/tcp

Next, create a polkit configuration file:

sudo nano /etc/polkit-1/localauthority.conf.d/02-allow-colord.conf

and input inside it:

polkit.addRule(function(action, subject) {
if ((action.id == “org.freedesktop.color-manager.create-device” || action.id == “org.freedesktop.color-manager.create-profile” || action.id == “org.freedesktop.color-manager.delete-device” || action.id == “org.freedesktop.color-manager.delete-profile” || action.id == “org.freedesktop.color-manager.modify-device” || action.id == “org.freedesktop.color-manager.modify-profile”) && subject.isInGroup(“{group}”))
{
return polkit.Result.YES;
}
});

Finally, restart xrdp and you should be able to connect:

sudo /etc/init.d/xrdp restart