I have just added ORANGE DMZ to my Ipfire system without issue. My server on ORANGE has internet access, no issues. By default, I have access from my desktop on GREEN to my server on ORANGE. Again no issues. If I enable my VPN on my desktop (ProtonVPN, GREEN network), I lose access to ORANGE. Is this expected behavior? If so, do I simply need a firewall rule to workaround?
Hi,
if the VPN client on your desktop machine enforces all traffic to be redirected through the VPN connection (which I suspect being default, as this is what most people associate with a VPN), you will not be able to connect to other local networks except for your default gateway anymore.
In this case, this problem is not related to IPFire.
Thanks, and best regards,
Peter Müller
Hello Peter,
Thank you for taking the time to respond. Would it be fair to say that even though my VPN allows local LAN connections (GREEN/BLUE) while active, ORANGE is not considered part of my local LAN?
Do you use / have you tried with internal orange ip?
I worked through this issue by adding my ORANGE subnet to my VPN. All is working well. 
Thank you for the assistance