Can you think of why this problem possibly happens? I'm running Opnsense as my firewall and everything works fine, until I reboot it. When I reboot it, Opnsense starts up correctly, but the internet DOES not work at all.
After many hours of debugging, I've figured out the way to fix this is to simply go to Firewall > NAT > Outbound and click Save, then Apply. The internet then starts working perfectly fine again.
I'm completely lost as to why this would happen, I know enough about networking to be dangerous, I've checked logs, I don't see anything "off", other that the symptom.
Any guesses or help would be appreciated. It's not too much of a problem as generally my FW is up for many months at a time, but still, it's an annoying bug that's persisted across versions.
Also I'm sorry for the lack of info regarding my setup, I'm not really sure what you'd want to see in this case, but I'll attach my NAT settings for you to review.
So...you only NAT UDP from LAN ? What about TCP traffic then ?