..bits & bytes teleported

Primary Link: http://www.virtualbox.org

Accessing the host operating system from a guest is as simple at setting up a network adapter attached to NAT and you will be able to access the Internet, ssh to the host and other things.

So how does this work?

The guest gets a IP address via DHCP which is made possible by the internal DHCP server of VirtualBox. The host also gets a IP address which is only accessible by the guest. We can think of it to be a internal IP address. Hence, we can “talk” to the host OS.

However, we cannot communicate in the same way with the guest OS from the host OS. This is expected as this is the very concept of NAT

Solution: Host Interface Networking

From the VirtualBox user manual:

“With Host Interface Networking, VirtualBox creates a new networking interface in software on the host computer. This new software interface will then exist in parallel to your regular interfaces (e.g., on a Linux host vbox0 will exist alongside eth0). When a guest is using such a new software interface, it looks to the host system as though the guest were physically connected to the interface using a network cable: the host can send data to the guest through that interface and receive data from it. This means that you can set up routing or bridging between the guest and the rest of your network.”

Set up a Network bridge to enable Host Interface Networking

The VirtualBox user manual has detailed instructions for setting up host interface networking on Windows, Linux and Solaris.

Here I will reproduce the steps for Ubuntu Linux 8.04.1

• Install the bridge-utils package: sudo apt-get install bridge-utils


• Edit your /etc/network/interfaces to add the following lines:
  



auto br0 <br />iface br0 inet static <br />address 10.10.3.4 <br /> bridge_ports eth0 <br />



• 
  Restart the networkin services: sudo /etc/init.d/networking restart


• Create a software host interface: sudo VBoxAddIF vbox0 amit br0 (where 'amit' should be the user who will be running VirtualBox)
  


• Modify the network settings of your virtual machine to add the interface 'vbox0' : VBoxManage modifyvm JeOS -hostifdev1 vbox0 (where 'JeOS' is your VM name)


• Boot up the VM and assign a static IP adress to the interface
  
  

Now you can access the Guest from the Host and vice-versa.

For eg. You can have a webserver running on your Guest OS and you can acces it from your Host.