Tag Archives: dhcp on ubuntu

Internet Connection Sharing on Ubuntu through Wireless

Yesterday, I tried to share the Internet connection from my laptop to iPhone through wireless and it’s really simple. These are the steps that I follow on my laptop that has Ubuntu 12.04 LTS:

Click on the “Network Manager” icon and from there,select “Create New Wireless Network…”:

Enter the details,according to your desire for this new “ad-hoc” network:

Note: For the WEP 40/128-bit Key option, you key has to be exactly 5/10/13 characters long.

Laptop will automatically connect to this new network we have just created:

Click on the “Network Manager” icon again and select “Edit Connections…”:

Select the “ad-hoc” connection that we created above and click on Edit button:

 Verify that the “Connect automatically” check-box is selected:

On the IPv4 Settings tab verify that the Method option is set to “Shared to other computers”:

Check the IP address for eth1(wireless):

Configuring the iPhone:

Hope this will help you!

Please Remember me in your prayers!

How to Install the DHCP Server on Ubuntu 12.04LTS

Ubuntu as DHCP Server:

To install dhcp server, enter the following command at a terminal prompt:

sudo apt-get install isc-dhcp-server

If there is more than one network card(s) in your Ubuntu server, then you have to select the network card on which your server will be listen for dhcp request. (By default, it listens on eth0).

You can change this by editing  /etc/default/isc-dhcp-server file:

sudo nano /etc/default/isc-dhcp-server

Change “eth0” to the interface on which you want that your server will listen for dhcp request (In my case, it is eth1):

It’s always a good practice to make a backup copy of /etc/dhcp/dhcpd.conf file:

sudo cp /etc/dhcp/dhcpd.conf /etc/dhcp/dhcpd.conf.bak 

Now we will change the default configuration by editing /etc/dhcp/dhcpd.conf, I normally delete everything inside the file and manually add the configuration that suits my needs 🙂

sudo nano /etc/dhcp/dhcpd.conf

Here is my dhcpd.conf file, you need to change it according to your needs:

ddns-update-style none;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;
option subnet-mask;
option broadcast-address;
option routers;
option domain-name-servers;
option domain-name "ubuntu.internal";
subnet netmask {

Restart dhcp service using the following command:

sudo service isc-dhcp-server restart 

Configure Windows as DHCP Client:

Just follow these steps, in order to configure your Windows machine as DHCP client (In my case, it’s Windows 7):

To check the IP Address on Windows 7:

To Check the DHCP Leases on Ubuntu Server:
sudo tail /var/lib/dhcp/dhcpd.leases

Hope this will help you!

Please Remember me in your prayers!

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