Host side

• Enable virtualization in the BIOS.
  To recover from a "VT-x is disabled" error on a Lenovo ThinkCentre, you must enable virtualization technology in the computer's BIOS settings. VT-x, or Intel Virtualization Technology, is a feature that allows a single physical processor to act as multiple virtual processors, which is essential for running virtual machines. Step-by-Step Recovery Restart the computer and immediately begin pressing the F1 key to enter the BIOS Setup Utility. This is the common key for ThinkCentre models, though some may use a different key. Once in the BIOS, use the arrow keys to navigate to the Advanced tab. From the Advanced menu, select CPU Setup and press Enter. Look for an option labeled Intel(R) Virtualization Technology and select it. Using the arrow keys, change the setting from Disabled to Enabled. Press the F10 key to save the changes and exit the BIOS. The computer will then restart.
• Create "Host key" if necessary (crescent moon on Sun 7):

  keycode 105 = Control_R NoSymbol Control_R

• Add this to /boot/loader.conf:

  vboxdrv_load="YES"                      # VirtualBox module
  atapicam_load="YES"
  

• Add this to /etc/rc.conf:

  vboxnet_enable="YES"                    # VirtualBox notworking
  hald_enable=YES

  hald_enable is probably already there for X.

• Add this to /etc/group:

  vboxusers:*:920:grog
  

  The entry for vboxusers was already there, but I had to add myself to be able to use it.

• Add this to /etc/devfs.conf:

  # For VirtualBox
  perm cd0 0660
  perm xpt0 0660
  perm pass0 0660
  

• Run VirtualBox and create a host interface (Settings/Network/tab Host-only Networks/ Green icon on right). Alternatively:

  === root@eureka (/dev/pts/20) ~ 71 -> VBoxManage hostonlyif create

  I'm not sure that this is right, nor that it is necessary.

Install from CD (image)

• Create a machine.

• Disk should be VDI, dynamically allocated.

• Select Bridged network.

• Point CD-ROM at an ISO image file. Boot and install as normal.

• After installation, set boot order (System/Motherboard) to HD first.

Install a Vbox image

This relates to FreeBSD images as found at ftp://ftp.freebsd.org/pub/FreeBSD/releases/VM-IMAGES/10.2-RELEASE/amd64/Latest/

• Download an image. I chose FreeBSD-10.2-RELEASE-amd64.vmdk.xz.
• Decompress the image:
  === grog@stable (/dev/pts/4) ~/VirtualBox 30 -> unxz FreeBSD-10.2-RELEASE-amd64.vmdk.xz

• Create a machine. Disk should be VMDK. Point at the image.

• Select Bridged network.

• Set boot order (System/Motherboard) to HD first. Boot.

• mkdir /eureka
  mount eureka:/ /eureka
  mount eureka:/home /eureka/home
  mount -p | tail -2 >> /etc/fstab
  ln -s /eureka/home/src /
  rm -rf /usr/src
  ln -s /src/FreeBSD/svn/ /usr/src
  ln -s /src/FreeBSD/svn/ports /usr/ports
  # Some of these don't build reliably
  cp -p /eureka/home/local/share/abbreviations ~
  cp -p /eureka/home/grog/.bashrc ~
  pkg install xterm cmake gmake bash emacs24 pkgconf openexr
  

• chsh to bash

• Add to /etc/rc.conf:

  rwhod_enable=YES
  

Attach an existing Vbox image