pi-hole and fritz.box: DHCP on fritz.box, devices in local network can only communicate partially

Help
1

Hello together!

I am having some connection issues in my local network with a pi-hole without active DHCP server and a fritz.box as the DHCP server. Some participants can access other local network participants, some not. I am currently clueless why this issue exist. I tried "Conditional Forwarding" as the fritz.box often seems to setup local device names, e.g. iphone.fritz.box - but I did not help. Any hints would be awesome!

Expected Behaviour:

Pi-hole and fritz.box co-exist within the network. The fritz.box is configured as the DHCP server in the local network (with address 192.168.178.1) and grants IP addresses in the range 192.168.178.0/24. Each device within this range can communicate with each other through the network. Pi-hole is setup under 192.168.178.111 as DNS server (without an active DHCP server).
I should be able to ping each device from another and establish a connection.

Actual Behaviour:

Some network participants can call each other, e.g. a computer via Ethernet connection can ping and reach a printer or the iPhone within the network. Another Macbook in the WiFi is able to ping 2 out of 3 wired devices and some wireless (WiFi) connected devices, but not the printer or the iPhone. As I am not fully aware why this inconsistency exist, help is appreciated. :slight_smile:

Debug Token:

https://tricorder.pi-hole.net/7NGidPeQ/

2

I don't have a Fritz!Box router, but Pi-hole documentation has a Fritz!Box guide:

3

You're using a public IP address range for your local network 192.178.168.0/24

These are address ranges you should use:

	•	10.0.0.0 to 10.255.255.255 (10.0.0.0/8)
	•	172.16.0.0 to 172.31.255.255 (172.16.0.0/12)
	•	192.168.0.0 to 192.168.255.255 (192.168.0.0/16)
4

I think it was a typo.

The debug log shows an IP in the correct range:

*** [ DIAGNOSING ]: Networking
[✓] IPv4 address(es) bound to the eth0 interface:
    192.168.178.111/24
5

I see.

@hacki Are you trying to ping these devices via their IP or DNS name? I have a Fritzbox myself, but I use Pi-hole as my DHCP-Server.

6

Thanks for the guide rdwebdesign! I double checked the configuration on the fritz.box and the configuration (besides the fritz.box version) is the same as in the guide and thus I think there should be no problem.

Yeah, the IP address was a typo on my end stonerl. :frowning:

Until you mentioned it, only the IP address and not their corresponding names. Just checked with the generated names of my fritz.box and their names resolve partially as with the IP addresses.