Installing Windows virtio drivers with Avocado-VT

So, you want to use Avocado-VT to install windows guests. You also want them to be installed with the paravirtualized drivers developed for windows. You have come to the right place.

A bit of context on windows virtio drivers install

This method of install so far covers the storage (viostor) and network (NetKVM) drivers. Avocado-VT uses a boot floppy with a Windows answer file in order to perform unattended install of windows guests. For winXP and win2003, the unattended files are simple .ini files, while for win2008 and later, the unattended files are XML files.

In order to install the virtio drivers during guest install, KVM autotest has to inform the windows install programs *where* to find the drivers. So, we work from the following assumptions:

  1. You already have an iso file that contains windows virtio drivers (inf files) for both netkvm and viostor. If you are unsure how to generate that iso, there’s an example script under contrib, inside the kvm test directory. Here is an example of how the files inside this cd would be organized, assuming the iso image is mounted under /tmp/virtio-win (the actual cd has more files, but we took only the parts that concern to the example, win7 64 bits).

If you are planning on installing WinXP or Win2003, you should also have a pre-made floppy disk image with the virtio drivers *and* a configuration file that the installer program will read to fetch the right drivers from it. Unfortunately, I don’t have much info on how to build that file, you probably would have the image already assembled if you are willing to test those guest OS.

So you have to map the paths of your cd containing the drivers on the config variables. We hope to improve this in cooperation with the virtio drivers team.

Step by step procedure

We are assuming you already have the virtio cd properly assembled with you, as well as windows iso files that *do match the ones provided in our test_base.cfg.sample*. Don’t worry though, we try as much as possible to use files from MSDN, to standardize.

We will use win7 64 bits (non sp1) as the example, so the CD you’d need is:

cdrom_cd1 = isos/windows/en_windows_7_ultimate_x86_dvd_x15-65921.iso
sha1sum_cd1 = 5395dc4b38f7bdb1e005ff414deedfdb16dbf610

This file can be downloaded from the MSDN site, so you can verify the SHA1 sum of it matches.

  1. Git clone autotest to a convenient location, say $HOME/Code/autotest. See the download source documentation Please do use git and clone the repo to the location mentioned.

  2. Execute the script (see the get started documentation <../GetStartedGuide>. It will create the directories where we expect the cd files to be available. You don’t need to download the Fedora 14 DVD, but you do need to download the winutils.iso. Our configuration is based on RHEL/Fedora based version that can be obtained from here <> and need to be placed in /tmp/kvm_autotest_root/isos/windows). Please, do read the documentation mentioned on the script to avoid missing packages installed and other misconfiguration.

  3. Create a windows dir under /tmp/kvm_autotest_root/isos

  4. Copy your windows 7 iso to /tmp/kvm_autotest_root/isos/windows

  5. Edit the file cdkeys.cfg and put the windows 7 64 bit key on that file

  6. Edit the file win-virtio.cfg and verify if the paths are correct. You can see that by looking this session:

        unattended_install.cdrom, whql.support_vm_install:
            # Look at your cd structure and see where the drivers are
            # actually located (viostor and netkvm)
            virtio_storage_path = 'F:\win7\amd64'
            virtio_network_path = 'F:\vista\amd64'
            # Uncomment if you have a nw driver installer on the iso
            #virtio_network_installer_path = 'F:\RHEV-Network64.msi'
  7. If you are using the cd with the layout mentioned on the beginning of this article, the paths are already correct. However, if they’re different (more likely), you have to adjust paths. Don’t forget to read and do all the config on win-virtio.cfg file as instructed by the comments.

  8. On tests.cfg, you have to enable virtio install of windows 7. On the block below, you have to change only rtl8139 to only virtio_net and only ide to only virtio-blk. You are informing autotest that you only want a vm with virtio hard disk and network device installed.

    # Runs qemu-kvm, Windows Vista 64 bit guest OS, install, boot, shutdown
    - @qemu_kvm_windows_quick:
        # We want qemu-kvm for this run
        qemu_binary = /usr/bin/qemu-kvm
        qemu_img_binary = /usr/bin/qemu-img
        # Only qcow2 file format
        only qcow2
        # Only rtl8139 for nw card (default on qemu-kvm)
        only rtl8139
        # Only ide hard drives
        only ide
        # qemu-kvm will start only with -smp 2 (2 processors)
        only smp2
        # No PCI assignable devices
        only no_pci_assignable
        # No large memory pages
        only smallpages
        # Operating system choice
        only Win7.64
        # Subtest choice. You can modify that line to add more subtests
        only unattended_install.cdrom, boot, shutdown
  9. You have to change the bottom of tests.cfg to look like the below, Which means you are informing autotest to only run the test set mentioned above, rather than the default, that installs Fedora 15.

    only qemu_kvm_windows_quick
  10. As informed on the output of, the command you can execute to run autotest is (please run this AS ROOT or sudo)

    $ $HOME/Code/autotest/client/bin/autotest $HOME/Code/autotest/client/tests/kvm/control
  11. Profit! You automated install of Windows 7 with the virtio drivers will be carried out.

If you want to install other guests, as you might imagine, you can change only Win7.64 with other guests, say only Win2008.64.sp2. Now, during the first time you perform your installs, it’s good to watch the installation to see if there aren’t problems such as a wrong cd key preventing your install from happening. Avocado-VT prints the qemu command line used, so you can see which vnc display you can connect to to watch your vm being installed.