22.3. FreeBSD as a Guest on Virtual PC for Windows®

Virtual PC for Windows® is a Microsoft® software product available for free download. See this website for the system requirements. Once Virtual PC has been installed on Microsoft® Windows®, the user can configure a virtual machine and then install the desired guest operating system.

22.3.1. Installing FreeBSD on Virtual PC

The first step in installing FreeBSD on Virtual PC is to create a new virtual machine for installing FreeBSD. Select Create a virtual machine when prompted:

Select Other as the Operating system when prompted:

Then, choose a reasonable amount of disk and memory depending on the plans for this virtual FreeBSD instance. 4GB of disk space and 512MB of RAM work well for most uses of FreeBSD under Virtual PC:

Save and finish the configuration:

Select the FreeBSD virtual machine and click Settings, then set the type of networking and a network interface:

After the FreeBSD virtual machine has been created, FreeBSD can be installed on it. This is best done with an official FreeBSD CD/DVD or with an ISO image downloaded from an official FTP site. Copy the appropriate ISO image to the local Windows® filesystem or insert a CD/DVD in the CD drive, then double click on the FreeBSD virtual machine to boot. Then, click CD and choose Capture ISO Image... on the Virtual PC window. This will bring up a window where the CD-ROM drive in the virtual machine can be associated with an ISO file on disk or with the real CD-ROM drive.

Once this association with the CD-ROM source has been made, reboot the FreeBSD virtual machine by clicking Action and Reset. Virtual PC will reboot with a special BIOS that first checks for a CD-ROM.

In this case it will find the FreeBSD installation media and begin a normal FreeBSD installation. Continue with the installation, but do not attempt to configure Xorg at this time.

When the installation is finished, remember to eject the CD/DVD or release the ISO image. Finally, reboot into the newly installed FreeBSD virtual machine.

22.3.2. Configuring FreeBSD on Virtual PC

After FreeBSD has been successfully installed on Microsoft® Windows® with Virtual PC, there are a number of configuration steps that can be taken to optimize the system for virtualized operation.

  1. Set Boot Loader Variables

    The most important step is to reduce the kern.hz tunable to reduce the CPU utilization of FreeBSD under the Virtual PC environment. This is accomplished by adding the following line to /boot/loader.conf:


    Without this setting, an idle FreeBSD Virtual PC guest OS will use roughly 40% of the CPU of a single processor computer. After this change, the usage will be closer to 3%.

  2. Create a New Kernel Configuration File

    All of the SCSI, FireWire, and USB device drivers can be removed from a custom kernel configuration file. Virtual PC provides a virtual network adapter used by the de(4) driver, so all network devices except for de(4) and miibus(4) can be removed from the kernel.

  3. Configure Networking

    The most basic networking setup uses DHCP to connect the virtual machine to the same local area network as the Microsoft® Windows® host. This can be accomplished by adding ifconfig_de0="DHCP" to /etc/rc.conf. More advanced networking setups are described in Chapter 32, Advanced Networking.

All FreeBSD documents are available for download at https://download.freebsd.org/ftp/doc/

Questions that are not answered by the documentation may be sent to <freebsd-questions@FreeBSD.org>.
Send questions about this document to <freebsd-doc@FreeBSD.org>.