Back to the Virtuality

Wednesday March 21st, 2012By: CyrIng

Following our post about FreeDOS virtualization, we now detail us the steps to boot the host PC with the virtualized hard disk.

1- Do a copy of the virtual hard disk’s image.

$ cd /tmp

$ cp -v /vm/KVM/freedos.img .
`/vm/KVM/freedos.img' -> `./freedos.img'

2- Compress the image : mandatory (¡.3)

$ gzip -v freedos.img
freedos.img: 76.6% -- replaced with freedos.img.gz

3- Create a directory near SysLinux in which the image will be stored.

$ sudo mkdir /boot/OS

$ sudo mv -v /tmp/freedos.img.gz /boot/OS/
`/tmp/freedos.img.gz' -> `/boot/OS/freedos.img.gz'

4- Add a new sub-menu into SysLinux. (¡.4)

$ sudo nano /boot/syslinux/syslinux.cfg

  • enter the following text at the end of the file
LABEL freedos
  LINUX memdisk
  INITRD ../OS/freedos.img.gz
  APPEND raw
  • save the file then quit the editor : press function keys [ F3 ] then [ F2 ]

5- Restart computer …

6- When the menu of SysLinux is displayed : press the [ D ] key to boot FreeDOS. (¡.1) (¡.2)

(¡) Remarks

  1. The image is first loaded into RAM then mapped as the C: drive.
    Any file changes will be lost during next reboot.
    Use floppies, USB thumb and flash cards to save your files.
  2. The amount of available disk space is what was left during the last virtualization.
  3. The virtual hard disk must be compressed.
    SysLinux loops if booting a not compressed image.
  4. A SysLinux configuration file is provided in the wiki.