Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have an eth0 and eth1, eth0 has dynamic IP-address and on eth1 I setup static IP-address:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp

auto eth1
iface eth1 inet static

and then I setup the isc-dhcp-server Install isc-dhcp-server with the following command:


Finally... I went to this one /etc/dhcpd.conf with the following command:

default-lease-time 650;

max-lease-time 79520;

option subnet-mask;
option broadcast-address;
option routers;

subnet netmask




When I try to sudo /etc/init.d/isc-dhcp-server start, I get start: Job failed to start

Anyone knows whats wrong?

share|improve this question
up vote 3 down vote accepted

You cannot have an 8 bit subnet mask an then use the network your subnet should be or change your mask to the later being an illegal subnet.

share|improve this answer

What does /var/log/syslog say?

isc's dhcpd is a bit picky in terms of the ip subnet parsing and ignoring bits. Suspect that the following may help in your setup: subnet netmask ^^^

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.