Recently, I needed to access an Azure VM from my Linux machine. I initially tried using standard Remote Desktop clients like Remmina and KRDC, but none of them could successfully connect.
The core roadblock has always been that Linux clients couldn’t handle the “Web Account Authentication” flow (enablerdsaadauth) that Microsoft Entra ID uses to trigger the MFA prompt.
After some troubleshooting, I realized the main issue was NLA (Network Level Authentication). NLA is enabled by default on Azure VMs, and the Linux clients I was testing either didn’t support it or only offered partial support.
I did read that the development branch of Remmina supposedly works if you use the “AAD” flag, but for whatever reason, I couldn’t get it to function properly in my environment.
Finally, after experimenting with a few different tools, I found that using xfreerdp was the most reliable solution.
xfreerdp /v:IP_ADDRESS /u:'AzureAD\EMAIL' /sec:aad /dynamic-resolution +clipboard /sound:sys:pulse /microphone:sys:pulse
dynamic-resolution: This flag allows the remote desktop session to dynamically adjust its resolution to match the screen size of the client.
sound:sys:pulse: This flag allows the remote desktop session to use the pulse audio server for sound output.
microphone:sys:pulse: This flag allows the remote desktop session to use the pulse audio server for microphone input.
clipboard: This flag allows the remote desktop session to use the clipboard for copy and paste operations.
REFERENCES
https://github.com/awakecoding/FreeRDP-Manuals/blob/master/User/FreeRDP-User-Manual.markdown
https://github.com/freerdp/freerdp/wiki/FAQ#connect-to-azure-virtual-desktop-avd