Funny enough, I do this as well (OpenBSD but with dnsmasq for easier DHCP/DNS integration). At the time I was having the DHCP issue, I had my OpenBSD router beh

Funny enough, I do this as well (OpenBSD but with dnsmasq for easier DHCP/DNS integration). At the time I was having the DHCP issue, I had my OpenBSD router behind my ISP's router in order to preserve some cable box functionality. I also kept "untrusted" devices like the Nest using that router. I've since ditched my cable boxes and thus the ISP router and now just have untrusted devices in a separate VLAN walled off from my other networks.