@Gblenn said in pfSense behind ISP modem (Double NAT) trouble:
I kind of looks ok, although it's confusing to see that VID is listed as untagged for ports 1 - 10, which includes port 2. Perhaps it's a limitation of the UI, and I would have expected it to read 1, 3-10. Sicne you don't want any VID 1 traffic ending up on port 2... Are you sure you are actually seeing the devices picking up DHCP from pfsense or is it from the modem?
I set port 2 to PVID 10 so the traffic from this port always falls into VLAN 10, I will try to disable this port for ID 1 however.
Also I will do a pcap and report my results later.