Howto force DHCP server working on a bridge?

Hi all ,

my pi-hole DHCP server is working on a bridge wlan0 <=> eth0 , but it seems it impossible to select the interface on the web GUI working with DHCP server .

i would like to do this because the DHCP not working correctly with wifi interface only .

i look at /etc/dnsmasq.d/02-pihole-dhcp.conf , but the file is overwritten .

so how can i tell the pi-hole DHCP server to work on my bridge ?

For additional dnsmasq configuration settings, put them in a new file in /etc/dnsmasq.d

hello and thanks fo the reply .

i had done this :

pi@rasphomfi:~ $ cd /etc/dnsmasq.d
pi@rasphomfi:/etc/dnsmasq.d $ ls -l
total 16
-rw-r--r-- 1 root root 1395 nov.   7 11:58 01-pihole.conf
-rw-r--r-- 1 root root  322 nov.   6 19:27 04-pihole-static-dhcp.conf
-rw-r--r-- 1 root root  375 nov.   6 18:55 05-addint.conf
-rw-r--r-- 1 root root  211 oct.   2  2017 README
pi@rasphomfi:/etc/dnsmasq.d $ sudo nano 05-addint.conf

and put it in the file :

pi@rasphomfi:/etc/dnsmasq.d $ cat  /etc/dnsmasq.d/05-addint.conf
## This will allow you to have pihole listen on specific interfaces other than what is listed in the webui
## the current pihole options are one, or all. this let's you be a bit more precise.

## test pour le pont eth0 <=> wlan0
interface=br0

## Openvpn Solution
#interface=tun0

## Ethernet
#interface=eth0

## Ethernet 2
#interface=eth1

# Wifi
#interface=wlan0

# Wifi 2
#interface=wlan1

## Vlan on eth0
#interface=eth0.1
pi@rasphomfi:/etc/dnsmasq.d $

Do you think that is do the trick ?

I believe that interface directive only applies to the DNS service and does not apply to the DHCP service (I could be wrong).
The DHCP service listening on port 67 UDP will bind to IP’s on all interfaces 0.0.0.0 :

pi@noads:~ $ sudo netstat -nltup | grep 'Proto\|:53 \|:67 \|:80 \|:471[1-8] '
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:53              0.0.0.0:*               LISTEN      15766/pihole-FTL
tcp        0      0 127.0.0.1:4711          0.0.0.0:*               LISTEN      15766/pihole-FTL
tcp        0      0 0.0.0.0:80              0.0.0.0:*               LISTEN      602/lighttpd
tcp6       0      0 :::53                   :::*                    LISTEN      15766/pihole-FTL
tcp6       0      0 ::1:4711                :::*                    LISTEN      15766/pihole-FTL
tcp6       0      0 :::80                   :::*                    LISTEN      602/lighttpd
udp        0      0 0.0.0.0:53              0.0.0.0:*                           15766/pihole-FTL
udp        0      0 0.0.0.0:67              0.0.0.0:*                           15766/pihole-FTL
udp6       0      0 :::53                   :::*                                15766/pihole-FTL

How is this bridge setup ?

sudo brctrl show

cat /etc/network/interfaces

tail -15 /etc/dhcpcd.conf

ip l

ip a

No Network Manager active ?

sudo service network-manager status

Below some pointers to setup bridge with dhcpcd5 that comes with Pi-hole:

pi@noads:~ $ apt policy dhcpcd5
dhcpcd5:
  Installed: 1:6.11.5-1+rpt7