root@DHCP1:~# more /etc/dhcp/dhcpd.conf

# dhcpd.conf
# Sample configuration file for ISC dhcpd
# Attention: If /etc/ltsp/dhcpd.conf exists, that will be used as
# configuration file instead of this file. < VERY IMPORTANT >
--------------------------------------------------------------
# option definitions common to all supported networks...
option domain-name "gns3lab.local";
option domain-name-servers ns1.gns3lab.local, ns2.gns3lab.local;
default-lease-time 600;
max-lease-time 7200;
--------------------------------------------------------------
# The ddns-updates-style parameter controls whether or not the server will
# attempt to do a DNS update when a lease is confirmed. We default to the
# behavior of the version 2 packages ('none', since DHCP v2 didn't have support for DDNS.)

ddns-update-style none;
---------------------------------------------------------------------------
# If this DHCP server is the official DHCP server for the local network, the authoritative directive should be uncommented.

authoritative;
-----------------------------------------------------------------------------
# Use this to send dhcp log messages to a different log file (you also have to hack syslog.conf to complete the redirection).

#log-facility local7;
-----------------------------------------------------------------------------
# No service will be given on this subnet, but declaring it helps the DHCP server to understand the network topology.

subnet 192.168.1.0 netmask 255.255.255.0 {
}
-------------------------------------------------------------------------------
# This is a very basic scope declaration.

# Scope 1 192.168.1.0 /24
subnet 192.168.1.0 netmask 255.255.255.0 {
range 192.168.1.150 192.168.1.200;
option routers 192.168.1.240;
}

# Scope 2 192.168.2.0 /24
subnet 192.168.2.0 netmask 255.255.255.0 {
range 192.168.2.150 192.168.2.200;
option routers 192.168.2.240;
}
-----------------------------------------------------------------------------------
#/EOF