UDP DNS traffic is dropped within GREEN network

Hi, for awhile now I am getting the below DROP_FORWARD between two IP addresses that both reside in the green network.

My firewall configuration

  1. drop all GRENN → RED for all DNS protocols
  2. allow only PiHole (IP) → RED for all DNS protocols

However even when i disable the above rules I am still getting the packages dropped

Any ideas where to look to find the root cause ?

Hint: it happens only for this specific client IP address


Try to change firewall rules priority.
Fisrt rule: authorize Pihole
2nd rule : block UDP 53 on all interfaces.


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the rules are actually on the order you have mentioned, but still, the issue happens without those rules too.

The qestion is why send the client in green ( the paket to the IPFire and not direkt to the DNS server ( which is in the same network.
Looks like a misconfiguration on the client.

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@arne_f this is what I cannot figure out… how the packet can go to IPFIRE first and then to the DNS proxy ?
The client IP is an android phone served by IPFIRE’s DHCP, while the is a static IP, and since both in Green they should be talking directly rather via IPFIRE.

Btw … I have fixed the lease on as with most of my network devices, but the issue only happens with this client.

I noticed the above is happening the moment the device is connecting to the WiFi… once is connected it doesn’t do this again unless it tries to reconnect, hence during the DHCP handshake …

Not sure if the following DHCP options somehow interfere…

I’ll try with static IP address so see if it reproduces

@arne_f, I have confirmed the issue doesn’t reproduce when the client is configured with a static IP