[colug-432] KVM vrtio under Windows

[Joshua Kramer]

In my configuration of Windows Vista and 2008 Server guests under KVM (on
CentOS 6.2 host), I found the disk performance to be excessively slow using
the IDE drivers.  So I wanted to use the virtio drivers instead; these
drivers work directly with KVM instead of forcing KVM to emulate IDE
hardware.  I downloaded the ISO of the driver disk from the KVM website
[1], and… no installer!  Under virtualbox, the virtualbox extensions have a
nice installer for both Windows and Linux guests.  The KVM driver ISO just
provides the raw .sys drivers.



What I did was the following:



1.       Shut down the Windows guest.

2.       Create a small (200MB) block device.

3.       Attach it to the Windows guest using the virtio interface (not
IDE).

4.       Attach the KVM virtio driver ISO image, to the CDROM drive present
on the Windows guest.

5.       Boot the Windows guest.

6.       After logging in, Windows “sees new hardware” and wants to install
a driver.  For Windows 2008 Server you can specify to search locally; for
Windows Vista (and I guess, Windows 7)  it has to search Windows Update
first and then it will ask you if you want to search local locations.

7.       After the drivers are installed in Windows, shut down the Windows
guest.

8.       Remove the ISO image, and the small virtio device, from the
Windows guest.

9.       Change the main storage device for the Windows guest from IDE to
virtio.

10.   Boot the windows guest.



I’m pretty sure that the virtio drivers are already present in the Linux
kernel.  I have a CentOS 6.2 guest that is configured just like my
webserver, so I’ll try to change its main storage to virtio and see if that
makes a difference…

____________________________________________________________
This message, including any attachments, may contain confidential
information intended for a specific individual and purpose, and may be
protected by law. If you are not the intended recipient please delete this
message immediately. Any disclosure, copying or distribution of this
message, or the taking of any action based on it, by any unintended
recipient is strictly prohibited.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.colug.net/pipermail/colug-432/attachments/20120330/bc29c453/attachment.html