By Fredrik Brattstig @virtualbrat
6 February 2024
Azure Virtual Desktop – DaaS! Well, now it’s not only DaaS, it’s also VDI! With the recent GA announcement Microsoft now supports running your AVD workloads on your own servers, in your own data center, in your own on-prem environment. What you need is all of the above and you need the installation media of Azure Stack HCI from here: https://learn.microsoft.com/en-us/azure-stack/hci/deploy/download-azure-stack-hci-23h2-software
The control plane will be in Azure, and with Azure ARC you will be able to provision AVD host pool members automatically on your own servers. The benefit of running AVD Workloads On-prem, as I see it, is latency reduction compared to if the workload runs in Azure. In my lab setup when I tested AVD on Azure Stack HCI the latency from my endpoints to my AVD hosts was <1ms, while my AVD hosts in Azure, using a VPN tunnel to connect my on-prem IGEL OS endpoints to my Azure tenant, was about 20ms. Those 20ms actually does make a difference when you compare the both in responsiveness of your session. Actually, having the chance to test AVD on-prem helped me to pinpoint a shortcoming in the IGEL AVD client, based on the Microsoft SDK, which was quickly fixed by IGEL and Microsoft developers when seen obvious. It’s a longer story but the TCP stack ran like “unoptimized”. All good now with the IGEL OS AVD client. Looking at session statistics like below is really nice:
So, what’s needed to connect your IGEL OS sessions to AVD on Azure Stack HCI to get the optimal performance?
First you will need to make sure that the IGEL OS endpoint has direct line of sight to the AVD hosts, it has to be able to resolve the AVD hosts dns name. The end goal is to connect the session from IGEL OS to your AVD worker to the IP-Address of the AVD host on UDP port 3390
You will also need to have a recent version of IGEL OS AVD app, which you have available for download from the IGEL App Portal for your IGEL OS 12 endpoints, and of course also baked in to IGEL OS 11 firmwares.
And lastly, you need to make sure that RDP-Shortpath is enabled for your session. You can find the configuration for this in IGEL OS 12 at:
IGEL Setup/Profile->Apps->AVD->AVD Sessions->%yourAVDsession%->Options->UDP Shortpath (default enabled)On IGEL OS 11, the configuration is made:
IGEL Setup/Profile->System->Registry->Sessions/%yourAVDSession%->Options->UDP-Short-Path->UDP Short Path (default disabled)And of course you will need to enable RDP-Shortpath on your AVD hosts according to Microsoft learn article: https://learn.microsoft.com/en-us/azure/virtual-desktop/configure-rdp-shortpath?tabs=managed-networks
If you want to read about my previous tests with AVD on Azure Stack HCI you can dig into the following two blogs:
https://virtualbrat.com/2023/06/28/igel-and-quake-ii-with-rtx-in-azure-virtual-desktop-have-you-seen-that-before-igel-os-azure-stack-hci-and-nvidia-a16-in-the-test-bench/
Enjoy your low latency sessions!
/Fred
VirtualBrat 