Straddling Multiple Networks safely using Virtual PC

Oh Man!!! Let a virus attempt to pass that Firewall!

If you need the functionality of 2 computers accessing two different networks on the same monitor and keyboard while using one physical machine, listen up!

I have a client that was subcontracting some work for another company. The other company moved in to an ajoining suite, so physical connection of the networks was possible. Some of my client's employees needed access to the LOB of both companies. That originally meant purchasing second computers for these employees and placing them on kvm switches. Cost was limiting how many employees could be setup this way.

What if we load virtual machines on the existing workstations? We can install a second network adapter in each computer to allow the virtual machine to connect to the second network. Tinker, install, load OS, expand memory... 2 hours later, it works! Duplicate virtual machine to additional computers. Client saves a bunch of money. IT consultant looks like he knows what he is talking about. Employees do not have to switch between 2 computers. Power utility sells less power. All positives!

Well... There were a couple of snags along the way.

SEPARATE THE NETWORKS : To make the networks not intermingle, attach the second adapter to the virtual machine. Then, uncheck all services on the second adapter inside the host OS except Virtual Machine services. Just run "ipconfig" on the host OS to verify that the second adapter does not appear. That way, neither the host nor the virtual can access both networks.

ERASE THE MAC ADDRESS : Open the vmc file for the virtual machine and erase the mac address. Don't worry. A dynamic mac address will be generated the next time the machine is started. If you don't do this, every copy of the virtual machine will have the same mac address and will pull the same ip address from DHCP. You will see some strange thing happen on your network then!

Hopefully this will encourage you to think of offbeat ways to use Virtual PC...