Configuration problem with a bridge

Pierre Couderc pierre at couderc.eu
Sun Feb 2 08:55:39 UTC 2020


Under debian buster and networking.service with a basic bridge.

DHCP does not assign addresses to enp5s0 devices, but assigns them 
correctly to br0 devices.

/etc/default/isc-dhcp-server :
INTERFACESv4="enp5s0 br0"


/etc/dhcp/dhcpd.conf :
subnet 192.168.16.0 netmask 255.255.255.0 {
range 192.168.16.51 192.168.16.99 ;
  authoritative;
}



/etc/networking interface :
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
auto enps5s0

iface enp5s0 inet manual

# The bridge :

auto br0

iface br0 inet static
         address 192.168.16.1
         netmask 255.255.255.0
         gateway 192.168.16.254
         network 192.168.16.0
         broadcast 192.168.16.255
         bridge_ports enp5s0
         bridge_stp on
         bridge_maxwait 0

iface enp5s0 inet6 auto


I have too in journalctl :

Feb 02 09:36:21 server dhcpd[874]: No subnet declaration for enp5s0 (no 
IPv4 addresses).
Feb 02 09:36:21 server dhcpd[874]: ** Ignoring requests on enp5s0.  If 
this is not what
Feb 02 09:36:21 server dhcpd[874]:    you want, please write a subnet 
declaration
Feb 02 09:36:21 server dhcpd[874]:    in your dhcpd.conf file for the 
network segment
Feb 02 09:36:21 server dhcpd[874]:    to which interface enp5s0 is 
attached. **

But there is only 1 subnet for devices "inside" br0 (lxd containers) and 
devices "outside".

It works fine if I install  isc-dhscp-server on another computer without 
bridge, but it is not what I want to do.

What do I miss ?






More information about the dhcp-users mailing list