DHCP server is used to assign IP
address to client computers and other Network devices . Basically we need
Ipaddress, Subnet mask, Gateway and DNS for network settings . We need to
define these values in the DHCP server, so that the client computer connected
to that network gets values automatically from DHCP server.
This guide helps you to setup DHCP
server on ubuntu 14.04.
Setup DHCP server on ubuntu 14.04
Before installation, Make sure you
have assigned static IP to the server.
Step 1 » Issue the below command to
update repository.
raja@linuxforfreshers:~$ sudo apt-get
update
Step 2 » Now install isc-dhcp-server
package and dependencies.
raja@linuxforfreshers:~$ sudo apt-get
install isc-dhcp-server -y
Step 3 » After installing, open
/etc/default/isc-dhcp-server file and assign interface.
raja@linuxforfreshers:~$ sudo nano
/etc/default/isc-dhcp-server
INTERFACES="eth0"
Step 4 » We need to define below
values in dhcpd.conf file located in /etc/dhcp/ directory.
Example scenario:
Network : 192.168.1.0/24
Range : 192.168.1.20 ( Starting IP ) –
192.168.1.100 ( Ending IP )
Gateway : 192.168.1.1
Primary DNS : 192.168.1.5
Sec DNS : 8.8.8.8
Take backup copy before making changes
to the original file .Better rename the file and create a new one .
raja@linuxforfreshers:~$ sudo mv
/etc/dhcp/dhcpd.conf
/etc/dhcp/dhcpd.conf.org
raja@linuxforfreshers:~$ sudo nano
/etc/dhcp/dhcpd.conf
and add the below code after making
changes as per your network values.
# option definitions common to all
supported networks...
default-lease-time 600;
max-lease-time 7200;
# 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;
subnet 192.168.1.0 netmask
255.255.255.0 { #network
range
192.168.1.10 192.168.100.100; # Range
option
domain-name-servers 192.168.1.5, 8.8.8.8; #Pri DNS , Sec DNS
option
domain-name "linuxforfreshers.com"; #Domain name
option
routers 192.168.1.1; #Gateway
option
broadcast-address 192.168.1.255; #Broadcast
default-lease-time
600;
max-lease-time
7200;
}
Step 5 » Now start/restart dhcp
service using the below command.
raja@linuxforfreshers:~$ sudo service
isc-dhcp-server restart
Address Reservation
Sometimes you need to reserve IP to
some devices like printers, camera, linux machines etc.
In this case, first you need to find
MAC Address of that device and define values in that particular subnet.
For example, Printer with
00:DD:HD:66:55:9B MAC Address has to be assigned with 192.168.100.50 IP. For
this, you need to add code like below to that subnet.
subnet 192.168.1.0 netmask
255.255.255.0 { #network
- - -
- -
max-lease-time 7200;
host printer-finance {
hardware ethernet
00:DD:HD:66:55:9B;
fixed-address 192.168.1.50;
}
host cam-gate {
hardware ethernet 00:KK:HD:44:55:22;
fixed-address 192.168.1.90;
}
}
and restart DHCP service.
raja@linuxforfreshers:~$ sudo service
isc-dhcp-server restart
