Stop resolving on multiple VLAN

[kevincork]

I think the issue might be from Ubiquiti - UNIFI but I removed the PiHole for a few day to try CloudFlare Team, and then as I went back to Pi-Hole yesterday I noticed that only the IoT vlan was resolved by Pi-Hole/Unbound.

I found out that the DNS settings forwarded by the router on the devices was wrong on the clients side (but right on the gateway). Client > DNS 1 PiHole, DNS 2 CloudFlare | Router DNS 1 > PiHole

The only way I managed to solve this is by enter the same PiHole server on all the DNS secondary server in the gateway.
however the issue remain with IPV6, whatever I keep entering the same IP

settings-wise in the PiHole, I don't see any configuration error, except that I didn't mention IPv6 for the Upstream DNS Servers (unbound) as the settings in never accepter, but that's a known bug I think and pretty sure I have the same settings before

[kevincork]

Resolved. the issue was from UNIFI as expected. I did enter the correct IPs but I left the switch to "auto" instead of manual....

[yubiuser]

@kevincork

Client > DNS 1 PiHole, DNS 2 CloudFlare

If you offer two different DNS server to the clients (via DHCP), the client decides which it will use. DNS 2 might be treated as fail over, but might be used on a regular basis as well.