I'm having quite strange behavior, I have an opnsense installation (very basic config) behind a router, under general--system I haven't set any DNS, I would like to use unbound for internal/external DNS resolution. opnsense acts as dhcp. apparently everything seems ok, I can navigate and opnsense's dnslookup resolves correctly, after a while (3/4 days) it no longer resolves, but if I restart opnsense without making any changes everything works again again, I tried to restart only unbound but it does not work
Checked Unbound logs?
Also, when problem occurs, run tcpdump (interface > Diagnostics > Packet Capture). Do you see DNS queries arriving from your clients?
If not, did your clients lose their DNS server address?
I'm running 24.1.10_3-amd64, no problems here.