@Pizzamaka said in unbound stops and won't start again + high cpu:
What still puzzles me is why starting unbound through UI does not work whereas running pfblocker update does start unbound.
Not 100% sure, but it could be that when killed unbound leaves behind its PID file in /var/run/. A shell script could potentially just unilaterally delete any existing unbound PID file before attempting to restart it. That's just a guess on my part, though, as I have not looked at the code in the pfBlockerNG scripts.
When you attempt to restart the DNS Resolver from the GUI, do you see anything in the pfSense system log at that time mentioning a PID file for unbound? If you do, that would validate my guess.