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For a network interface, I have defined a range of addresses for DHCP.

3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000
link/ether 08:00:27:5a:3e:be brd ff:ff:ff:ff:ff:ff
inet brd scope global eth1

and the dhcpd.conf file contains

subnet netmask {
  allow booting;
  allow bootp;
  class "pxeclients" {
    match if substring(option vendor-class-identifier, 0, 9) = "PXEClient";
    filename "pxelinux.0";

However, when I start the dhcpd, i get this error

/etc/dhcp/dhcpd.conf line 1: subnet netmask bad subnet number/mask combination.
subnet netmask 
Configuration file errors encountered -- exiting

What is the problem?

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up vote 3 down vote accepted

You gave an IP address inside the subnet instead of the address of the subnet itself. Replace subnet with subnet, and it should work.

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