Howto share your internet connection in Ubuntu.

Since Ubuntu 9.10 Karmic Koala, Ubuntu has an inbuilt way of sharing any connection. There are a couple usage scenarios for this:-

  1. You want to share your mobile broadband connection with other computers on the network
  2. You want to use your Ubuntu machine to extend your network wirelessly e.g. Your laptop is connected to the network via it’s wireless adapter, which is then connected to another machine via a CAT 5 or CAT 6 cable, enabling the other machine to connect to the network and internet.

I wouldn’t envisage using this to share a DSL broadband connection since most people will already be using an ISP supplied router to do this.

Using it is as simple as enabling the method “Shared to other computers” in the network connection in network manager.

This turns your machine into a mini DHCP/DNS server and starts handing out IP addresses in a 10.x.x.x address range. The machine then NAT/routes any traffic coming in on that interface and forwards it to the networks real gateway. I’ve used it a few times now and it works well.


Setup DNS, DHCP and Content Filtering using DNSMASQ and HAVP in Ubuntu.

The idea here is to setup DNSMASQ and HAVP to provide DNS, DHCP and content filtering in a Windows 7/Vista/XP client environment on Ubuntu Server Edition. DNSMASQ is a light package which will provide DNS caching and DHCP to a network (amongst other things). HAVP is a proxy server which uses a third party virus scanner (usually ClamAV)┬áto scan internet content for viruses. This assumes that you already have Ubuntu Server Edition installed on a suitable machine and have a working internet connection. In the settings “” refers to this machine which is acting as a router/firewall, you could equally set it to the ip of another router on the network. “” refers to the ip of a Windows server. First off install DNSMASQ:-

apt-get install dnsmasq

Edit “/etc/dnsmasq.conf”:-

nano -w /etc/dnsmasq.conf

We now need to set the relevant options:-

Continue reading Setup DNS, DHCP and Content Filtering using DNSMASQ and HAVP in Ubuntu.