KVM, windows 2000 and qcow2

KVM, windows 2000 and qcow2

[RaSca]

Hi guys,
I'm facing some problems in keeping my Windows 2000 virtual machines up 
and running. Every machine resides on a drbd storage, with this disk setup:

     <disk type='block' device='disk'>
       <driver name='qemu' type='raw'/>
       <source dev='/dev/drbd0'/>
       <target dev='hda' bus='ide'/>
       <address type='drive' controller='0' bus='0' unit='0'/>
     </disk>

I installed the virtual machine without any problem, but sometimes  it 
freeze. I mean, the only way I have to make it work again is killing the 
kvm process by hand:

/usr/bin/kvm -S -M pc-0.12 -enable-kvm -m 512 -smp 
1,sockets=1,cores=1,threads=1 -name vm-win2k -uuid 
806d0e99-b164-c77d-96eb-55d24d3ba06b -nodefaults -chardev 
socket,id=monitor,path=/var/lib/libvirt/qemu/vm-win2k.monitor,server,nowait 
-mon chardev=monitor,mode=readline -rtc base=localtime -boot c -drive 
file=/dev/drbd0,if=none,id=drive-ide0-0-0,boot=on,format=raw -device 
ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -drive 
file=/root/vmwarevga32-kvm.iso,if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw 
-device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 
-device rtl8139,vlan=0,id=net0,mac=52:54:00:a3:5b:1b,bus=pci.0,addr=0x3 
-net tap,fd=44,vlan=0,name=hostnet0 -chardev pty,id=serial0 -device 
isa-serial,chardev=serial0 -usb -device usb-tablet,id=input0 -vnc 
0.0.0.0:0 -k it -vga vmware -device 
virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4

and restart the machine with virsh start.
Today i saw this page:

http://www.linux-kvm.org/page/Guest_Support_Status

in which is explained how is better to run win2k on qcow2 images.
My question are: is this the reason why my machines freezes? Is it 
mandatory using qcow2 images to have stable machines? How using directly 
drbd make things worst? Is there a way for using qcow2 images WITH drbd? 
I mean, without formatting drbd with ext3 and put the image on it...

Thanks a lot,

-- 
Raoul Scarazzini
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
rasca@miamammausalinux.org

Re: KVM, windows 2000 and qcow2

[RaSca]

Il giorno Mar 09 Nov 2010 21:43:36 CET, Dan VerWeire ha scritto:
[...]
> I sadly cannot help with your specific issue but I did want to report
> that I have many Windows 2000 virtual machines backed by LVM or DRBD on
> LVM without any issues. Most of these instances have seen more than 180
> day up-times. I have also had several VMs backed with raw files also
> without issue. So, in my experience, qcow2 is not mandatory for Windows
> 2000.
> Best regards,
> Dan VerWeire

I know that this may seem strange, but I think the problem is VNC. Do 
you use VNC or Remote Desktop to connect to those Win2k? My setup is 
identical to yours: LVM -> DRBD -> KVM.

Thanks,

-- 
Raoul Scarazzini
Mia Mamma Usa Linux: Niente è impossibile da capire, se lo spieghi bene!
mobile: +393281776712
rasca@miamammausalinux.org
http://www.miamammausalinux.org

Re: KVM, windows 2000 and qcow2

[Jernej Simončič]

On Tuesday, November 9, 2010, 21:06:49, RaSca wrote:

> in which is explained how is better to run win2k on qcow2 images.
> My question are: is this the reason why my machines freezes?

Very unlikely - using a block device directly is usually both the
fastest and most reliable way to run a guest OS.

You are using -vga vmware - in my experience, Qemu's VMWare VGA
emulation isn't very reliable with Windows guests (redraw problems).
-vga std and the AnaPa VESA driver (for Windows 2000, which doesn't
have native VESA driver) work the fastest (-vga cirrus also works, but
it's slightly slower for some reason).

How does the VM freeze - is there a BSOD? What's qemu-kvm's CPU usage
when the VM freezes?

-- 
< Jernej Simončič ><><><><>< http://eternallybored.org/ >

Murphy was an optimist...
       -- O'Toole's Commentary on Murphy's Laws

Re: KVM, windows 2000 and qcow2

[Dan VerWeire]

On Tue, Nov 9, 2010 at 4:21 PM, RaSca <rasca@miamammausalinux.org> wrote:
>
> Il giorno Mar 09 Nov 2010 21:43:36 CET, Dan VerWeire ha scritto:
> [...]
>>
>> I sadly cannot help with your specific issue but I did want to report
>> that I have many Windows 2000 virtual machines backed by LVM or DRBD on
>> LVM without any issues. Most of these instances have seen more than 180
>> day up-times. I have also had several VMs backed with raw files also
>> without issue. So, in my experience, qcow2 is not mandatory for Windows
>> 2000.
>> Best regards,
>> Dan VerWeire
>
> I know that this may seem strange, but I think the problem is VNC. Do you use VNC or Remote Desktop to connect to those Win2k? My setup is identical to yours: LVM -> DRBD -> KVM.


I use VNC on every one. Remote Desktop is used only on the machines
that are intended to be Terminal Servers. Here is what my host is
using:

Intel(R) Xeon(R) CPU E5430  @ 2.66GHz
2.6.32-24-server x86_64
Ubuntu 10.04.1 LTS
qemu-kvm-0.12.3

Re: KVM, windows 2000 and qcow2

[Stefan Hajnoczi]

On Tue, Nov 9, 2010 at 8:06 PM, RaSca <rasca@miamammausalinux.org> wrote:
> Today i saw this page:
>
> http://www.linux-kvm.org/page/Guest_Support_Status
>
> in which is explained how is better to run win2k on qcow2 images.

The page does not state that it is better to run Windows 2000 on
qcow2, it's probably just that the tester decided to use qcow2 on his
machine and noted his configuration.

Raw should work just like qcow2 does and you can expect better
performance with raw.  Although qcow2 does run on raw devices like
drbd or lvm logical volumes, I suspect you'll see the same issue
you're getting now.

It's worth figuring out why your current configuration freezes.  I am
interested in the same questions Jernej asked about the freeze: is the
guest crashing with a BSOD or is the KVM process consuming all CPU?

Stefan