I am not new to opnsense. I have been using it almost a year. Yesterday I made a change that caused all internet access to be lost on my vlans. Let me first explain my setup. On my box the first physical port is the LAN interface. It is used only to administer opnsense and normally has nothing connected. The second is the WAN port. It connects directly to the ISP's modem. The third port connects to my old consumer WiFi mesh network. I use it for guest access and phones. The third connects to an access point and is used for most iot devices. The fourth is my vlans. It connects to an ethernet power adapter. Then at various points in the house I have other power adapters that connect to smart switches. In my office I have one vlan for my wired linux computers, another for my wired windows computers. In my wife's office I connect to an access point for her windows laptap. The wired computers do not use dhcp, the laptop does. Opnsense captures all port 53 requests and routes them to 127.0.0.1. Unbound then routes them over DOT to a DNS provider.
Yesterday my daughter was visiting and working. Her employer uses Microsoft teams. I had to open some ports on the guest interface so she could work. She was happy. Later my wife reported she had no internet access. Hugh? I didn't change any of the vlan interfaces. To get her going I connected her computer to the phone WiFi. Later I noticed none of the vlans in my office had internet either. Although it shouldn't matter I disbled the rule I added earlier in the day on the guest interface and vola! Internet access returned to all the vlan interfaces. Hugh?! I then reactivated the rule and internet access was still there. Now I may not be a newbe but I am no expert either so I figured let me put this out there to see if anyone out there has any idea what happened.