I'm still struggling with this! Anyone else have some thoughts or inputs? I have read a few things about Untangle stripping off VLAN tags. I don't exactly comprehend this being as Untangle clearly has the option under networking to add a Tagged VLAN interface.
One thought I am having is potential for the 1 internal NIC to serve as both a physical and virtual interface. (ie:the physical internal nic directly handles the default VLAN 1 with DHCP and a 192.168.0.1 IP range. Should I be bridging the internal interface to all VLAN interfaces and creating a VLAN 1, 10, and 20? This would make all interfaces essentially virtual or VLANs.