And Now For Something Completely Different. Win7 On KVM

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As you can probably guess by now I am working my way down through my outstanding issue list trying to get as many deferred items closed out as I
can before the next security storm hits.

We have a Win7pro KVM guest that has been giving us networking issues since it was created. The last problem was that it was picking up its network address from the virtio DHCP service, with predicable results. This turned out to be an issue with how the virtual nic was configured (it was using NAT instead of the br0 bridge.

We have adjusted the settings on the guest so the the nic is configured as a shared device / br0 / Device Model=virtio. Now after it boots the thing says that it does not have a driver for Ethernet adaptor at all. Is there a different setting for the model that I should be using?

I have to point out that this thing was originally installed from cd-rom and then updated from the internet. So at some point it must have had a working network connection. Any ideas as to how to get it to find the network interface again?

10 thoughts on - And Now For Something Completely Different. Win7 On KVM

  • Op 22-10-14 om 23:15 schreef James B. Byrne:

    James,

    on the client, which driver do you use? Mine is ‘Red Hat VirtIO Ethernet Adapter’ 61.65.104.7400 20/11/2013. I got it from virtio-win-0.1-74.iso

    Patrick

  • Am 23.10.2014 um 08:58 schrieb Patrick Bervoets:

    [ … ]

    A newer VirtIO Driverpack can be found here:

    https://alt.fedoraproject.org/pub/alt/virtio-win/latest/images/

    I can only guess that the Windows VM hadn’t been configured before to use any VirtIO interface, neither for network, nor for VirtDisk access. OP should install the drivers from the ISO and then switch the disk device model as well to VirtIO for best performance.

    Alexander

  • At the moment none I guess. The message is that the client cannot find a driver. I have virtio-win-0.1-74.iso and virtio-win-0.1-81.iso on the hypervisor host. How do I get the driver from there into the guest? Does the client have access to the hypervisor’s file-systems? Do I mount the ISO as a cd-rom in the guest? How is that done? In virt-manager? Is there a document somewhere that I can get an idea on how this is supposed to work?

    Bear in mind that other than the occasional configuration and diagnostic issue I have very, very little experience with MS-Win since XPsp3 and none at all in running it as a guest on KVM.

  • I am in the eye of the hurricane more likely. But I will take whatever calm I
    can find. For however long it lasts.

  • Yes, you attach the ISO to the CD-ROM of the guest. From there the guest can access the ISO as if it was a normal CD-ROM.

    I’ve used VirtIO drivers with WinXP, 7, and 8 in the past without network or disk performance issues. They’re test VMs only seeing occasional usage, but they perform quite well. VirtIO is the way to go.

  • Op 23-10-14 om 18:00 schreef James B. Byrne:

    James,

    I don’t know if help is still needed.

    You can mount the iso via virt-manager if you have (or create) a virt-storage-pool.

    If you can reboot the client you could edit /etc/libvirt/qemu/virtclientname.xml and add


    to

    (if your client already has more than 2 drives attached, change target dev hdc to hdd or …)

    You can switch your storages to virtio too, I did it in the past but fail to find my notes.

    I think that the steps on this page are correct:
    http://setdosa.blogspot.be/2013/09/moving-your-windows-guest-from-ide-to.html

    And, of course, work on a snapshot or at least have a copy of your client.

    If you need help to change the driver in Windows I suggest we take this off-list since some are very allergic to Microsoft.

    Patrick

  • Trust me. I am always in need of help.

    They are already virtio.

    At the moment all I am looking for is how to use the CentOS tools to mount a guest system. So I think that probably falls in the scope of this list. If
    (when) I get into trouble on the Win side of things then I will take you up on your kind offer.

    Per your suggestion I used virt-manager to open the guest and added a hardware device. I selected the option “Select managed or other existing storage”, browsed for the virtio-win.iso and set the Device type to IDE CDROM with storage type ‘raw’. I started the guest and the new CDROM shows in the hardware list.

    I will see how it goes from there.

    Thanks again,

  • No, I was looking at something else. The HDD are IDE. I will check into moving those to virtio as well.

  • OK. We are golden with respect to getting the network reactivated on the Windows guest. One down, infinity to go. Thanks for the help.

    There was one wrinkle in all this. I had to log on to the guest as a local administrator to configure the nic driver. Windows explorer (not IE) reported a server error when I logged in as the domain admin and tried to open the computer management window.

    Explorer.exe server execution failed.

    And in consequence I could do absolutely nothing until I logged in with a local user profile.

    This is apparently due to the fact that Win7 handles roaming user profiles somewhat differently than WinXp. Evidently, if you do not have a network connection to a remote user profile then the OS chokes. Just a heads up for anyone else in this situation.