Installation guide

Chapter 28.
243
Miscellaneous storage topics
28.1. Creating a virtualized floppy disk controller
Floppy disk controllers are required for a number of older operating systems, especially for installing
drivers. Presently, physical floppy disk devices cannot be accessed from virtualized guests. However,
creating and accessing floppy disk images from virtualized floppy drives should work. This section
covers creating a virtualized floppy device.
An image file of a floppy disk is required. Create floppy disk image files with the dd command.
Replace /dev/fd0 with the name of a floppy device and name the disk appropriately.
# dd if=/dev/fd0 of=~/legacydrivers.img
This example uses a guest created with virt-manager running a fully virtualized Fedora installation
with an image located in /var/lib/libvirt/images/Fedora.img.
1. Create the XML configuration file for your guest image using the virsh command on a running
guest.
# virsh dumpxml Fedora > Fedora.xml
This saves the configuration settings as an XML file which can be edited to customize the
operations and devices used by the guest. For more information on using the virsh XML
configuration files, refer to Chapter 33, Creating custom libvirt scripts.
2. Create a floppy disk image for the guest.
# dd if=/dev/zero of=/var/lib/libvirt/images/Fedora-floppy.img bs=512 count=2880
3. Add the content below, changing where appropriate, to your guest's configuration XML file. This
example is an emulated floppy device using a file-based image.
<disk type='file' device='floppy'>
<source file='/var/lib/libvirt/images/Fedora-floppy.img'/>
<target dev='fda'/>
</disk>
4. Force the guest to stop. To shut down the guest gracefully, use the virsh shutdown command
instead.
# virsh destroy Fedora
5. Restart the guest using the XML configuration file.
# virsh create Fedora.xml
The floppy device is now available in the guest and stored as an image file on the host.