Configure DHCP Server on Red Hat Enterprise Linux 5

DHCP Server Configuration

Step-1:  To check dhcp  rpm package is installed or not by following this command:

                       

(if installed then it will show dhcp packages)

[root@dhcp ~]# rpm -qa | grep –i dhcp*    or

[root@dhcp ~]#  rpm –qa dhcp*

dhcp-3.0.5-21.el5

dhcp-devel-3.0.5-21.el5

libdhcp-devel-1.20-10.el5

dhcpv6-client-1.0.10-17.el5

libdhcp-1.20-10.el5

libdhcp4client-3.0.5-21.el5

libdhcp6client-devel-1.0.10-17.el5

libdhcp4client-devel-3.0.5-21.el5

dhclient-3.0.5-21.el5

           If not installed, then installed the packages using  Yum command:

[root@dhcp ~]# Yum Install dhcp* lib*

Step-2: Check and Configure the Network Card:

[root@dhcp ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

(Original File):

#Broadcom Corporation Net link BCM57875 Gigabyte Ethernet PCI Express

DEVICE=eth0
BOOTPROTO=dhcp
HWADDR=00:0C:29: EB: B2: CA
ONBOOT=yes

(Modified File):

#Broadcom Corporation Net link BCM57875 Gigabyte Ethernet PCI Express

DEVICE=eth0

BOOTPROTO=static

HWADDR=00:0C:29: EB: B2: CA

ONBOOT=yes

TYPE=Ethernet

PEERDNS=no

USERCTL=no

IPV6INIT=no

IPADDR=210.207.201.4

NETMASK=255.255.255.0

NETWORK=210.207.201.0

BROADCAST=210.207.201.255

Press Esc → Shift + : → x! → Enter (For Save and Exit the Vi Editor).

After changing you have to reload/restart the NIC(eth0) card by following command:

[root@dhcp ~]# ifdown eth0

[root@dhcp ~]# ifup eth0

[root@dhcp ~]# service network restart

Step-3:  After complete the NIC configure you have to change the host name by following this                             command:

[root@dhcp ~]# vi /etc/sysconfig/network

(Original File):

NETWORKING=yes

NETWORKING_IPV6=no

HOSTNAME=localhost.localdomain

(Modified File):

NETWORKING=yes

NETWORKING_IPV6=no

HOSTNAME=dhcp

Press Esc → Shift + : → x! → Enter

Step-3:  Edit the resolv.conf file by following this command

[root@dhcp ~]# vi /etc/resolv.conf

search alphabd.net

nameserver 210.207.201.1

nameserver 210.207.201.2

Step-4:  Copy & Rename the DHCP configuration file & Change the permission by following this                                command:

[root@dhcp ~]# cd /usr/share/doc/dhcp-3.0.5/

[root@dhcp dhcp-3.0.5]# cp dhcpd.conf.sample  /etc/dhcpd.conf

[root@dhcp dhcp-3.0.5]# chmod 777 /etc/dhcpd.conf

Now Edit this file using vi editor & make some change in to this file.

[root@dhcp ~]# vi /etc/dhcpd.conf

(Original File):

ddns-update-style interim;

ignore client-updates;

subnet 192.168.0.0 netmask 255.255.255.0 {

# --- default gateway

      option routers                192.168.0.1;

      option subnet-mask            255.255.255.0;

      option nis-domain       "domain.org";

      option domain-name            "domain.org";

      option domain-name-servers    192.168.1.1;

      option time-offset            -18000;     # Eastern Standard Time

#     option ntp-servers            192.168.1.1;

#     option netbios-name-servers   192.168.1.1;

# --- Selects point-to-point node (default is hybrid). Don't change this unless

# -- you understand Netbios very well

#     option netbios-node-type 2;

      range dynamic-bootp 192.168.0.128 192.168.0.254;

      default-lease-time 21600;

      max-lease-time 43200;

      # we want the nameserver to appear at a fixed address

      host ns {

            next-server marvin.redhat.com;

            hardware ethernet 12:34:56:78:AB:CD;

            fixed-address 207.175.42.254;

      }

}

(Modified File):

ddns-update-style interim;

ignore client-updates;

subnet 210.207.201.0 netmask 255.255.255.0 {

# --- default gateway

      option routers                210.207.201.4;        

      option subnet-mask            255.255.255.0;

#     option nis-domain       "domain.org";

      option domain-name            "alphabd.net";        

      option domain-name-servers    210.207.201.1;

      option time-offset            -18000;     # Eastern Standard Time

#     option ntp-servers            192.168.1.1;

#     option netbios-name-servers   192.168.1.1;

# --- Selects point-to-point node (default is hybrid). Don't change this unless

# -- you understand Netbios very well

#     option netbios-node-type 2;

      range dynamic-bootp 210.207.201.50 210.207.201.254;

      default-lease-time 43200;

      max-lease-time 86400;

      # we want the nameserver to appear at a fixed address

      host ns {

            next-server marvin.redhat.com;

            hardware ethernet 12:34:56:78:AB:CD;

            fixed-address 207.175.42.254;

      }

      host pc01 {

            hardware ethernet 00:1E:68:91:BB:EC;

            fixed-address 210.207.201.100;

      }

      host client01 {

            hardware ethernet 00:0C:29:8C:95:01;

            fixed-address 210.207.201.150;

      }

}

Esc → Shift + : → x! → Enter

Step-5:  Create a dhcp.leases file that the DHCP server grants to the DHCP client to use a particular IP   address. If it does not exist dhcp server will fail to provide IP address for dhcp cient.

[root@dhcp ~]# touch /var/lib/dhcpd/dhcpd.leases

[root@dhcp ~]# service network restart

[root@dhcp ~]# service dhcpd restart

Step-6:   Client Configuration for using DHCP.

Linux Client

[root@dhcp ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0

#Broadcom Corporation Net link BCM57875 Gigabyte Ethernet PCI Express

DEVICE=eth0
BOOTPROTO=dhcp
HWADDR=00:0C:29: EB: B2: CA
ONBOOT=yes

TYPE=Ethernet

Windows Client

From NIC Properties =>> set Obtain an IP Address Automatically

Step-7:   Renewing IP Address

Renew an IP Address in Linux

The -r flag explicitly releases the current lease, and once the lease has been released, the client exits. For example, open terminal and type the command:

[root@dhcp ~]# dhclient –r

Now obtain fresh IP:

[root@client1 ~]# dhclient

Or you can put the two commands on a single line:

[rnbsp; oot@client1 ~]# dhclient -r; dhclient

There is no need to restart network service. Above command should work with any Linux distro such as RHEL, Fedora, and others. On a related note you can also try out the following commands:

[root@client1 ~]# ifdown eth0
[root@client1 ~]# ifup eth0
[root@client1 ~]# /etc/init.d/network restart

Renew an IP Address in Windows

Open Command Prompt → Then Type The following command

C:\Documents and Settings\Administrator> Ipconfig  /release

C:\Documents and Settings\Administrator> Ipconfig  /renew

C:\Documents and Settings\Administrator> Ipconfig  /all