This is a little howto where I explain how I configured bridged networking for virtualbox with static ips on an Ubuntu host in order to make the virtual machine accessible from outside the host system.
sudo aptitude install bridge-utils uml-utilities sudo adduser $USER uml-net
Login again so the change takes effect.
Modify /etc/network/interfaces so it has the following content:
auto lo iface lo inet loopback iface eth0 inet static address 0.0.0.0 auto eth0 auto tap0 iface tap0 inet manual up ifconfig $IFACE 0.0.0.0 up down ifconfig $IFACE down tunctl_user david auto br0 iface br0 inet static address 192.168.0.12 network 192.168.0.0 netmask 255.255.255.0 broadcast 192.168.0.255 gateway 192.168.0.1 bridge_ports eth0 tap0
sudo /etc/init.d/networking restart
Open virtualbox. Click on settings and choose network. Where it says “Attached to” select Host Interface. In the text field labeled “Interface Name” insert tap0.
Boot your guest OS and configure networking under your guest OS the same way you would configure any other machine on your local LAN.
Chapter 6, Virtual Networking, from the Virtualbox User Manual