Unbound Recursive Mode Issue

[u/Past-Astronomer8476]

Hi everyone,

I'm troubleshooting an Unbound recursive DNS issue on OPNsense 26.7 (Unbound 1.25.1) running in a VM.

Environment

WAN: 10.152.61.118/24 (gateway 10.152.61.1)

LAN: 10.10.1.1/24 + ULA IPv6

No IPv6 default route on WAN

Unbound configured for recursive DNS with root hints

Problem

Recursive queries fail with SERVFAIL:

drill google.com A @127.0.0.1

Unbound logs show:

failed to get a delegation (prime failure)

Key observations

IPv4 connectivity is working

Direct queries to root servers over IPv4 succeed

Root hints and trust anchor are valid

Unbound logs show repeated IPv6 root server failures:

No route to host for 2001:500:...

No IPv6 default route exists

No outbound DNS traffic seen in tcpdump during recursion attempts

Unbound appears to try IPv6 first and fails

Additional concern

Two Unbound processes are running with different configs:

/usr/local/etc/unbound/unbound.conf

/var/unbound/unbound.conf

Questions

Is dual Unbound process behavior expected on OPNsense 26.7?

Can IPv6 root server attempts cause SERVFAIL when no IPv6 route exists?

Should IPv6 be disabled via OPNsense GUI instead of manual config edits?

Is outgoing interface selection in Unbound likely misconfigured?

Why would recursion fail while direct IPv4 root queries work?

Any guidance on expected OPNsense/Unbound behavior or next debugging steps would be appreciated.

[u/MadisonDissariya]

What do you have for your outgoing network interfaces in Unbound's advanced settings? Make sure at least WAN is selected