Re: [Qemu-devel] Qemu Questions

[address@hidden]

Forgot to add.
I gave up on virt-install long ago due to the fact that it cannot configure a guest on FC7.
I just used the qemu command line instructions and switches and it worked flawlessly to install 98/ME/XP/DOS and whatsoever.

These run on 4 core Rackservers.
See below at Appendix:

Configuring DHCP in virt-manager doesnt work at all, the windows guest searches by means of DHCP for an IP address, but nothing is forwarded.
Can it also work without having to set DHCP with virt manager?
Is the DHCP daemon on the Linux host not sufficient?





Appendix:----------------------------------------------------------------------------------------------------------------------------------------------------

FYI
I get the following errors: and virt-install seems broken on FC-7 as I can successfully install with qemu CLI.

address@hidden ~]# virt-install
What is the name of your virtual machine? WinME-1
How much RAM should be allocated (in megabytes)? 1000
What would you like to use as the disk (path)? /home/xen/winme.img
How large would you like the disk (/home/xen/winme.img) to be (in gigabytes)? 3
Would you like to enable graphics support? (yes or no) yes
What is the install location? /dev/scd0


Starting install...
libvir: Xen Daemon error : GET operation failed:
Invalid file location given: No such file or directory
Domain installation may not have been
successful.  If it was, you can restart your domain
by running 'virsh start WinME-1'; otherwise, please
restart your installation.
Thu, 08 Nov 2007 07:25:03 ERROR    Invalid file location given: No such file or directory
Traceback (most recent call last):
File "/usr/sbin/virt-install", line 474, in <module>
  main()
File "/usr/sbin/virt-install", line 438, in main
  dom = guest.start_install(conscb,progresscb)
File "/usr/lib/python2.5/site-packages/virtinst/Guest.py", line 706, in start_install
  self._prepare_install(meter)
File "/usr/lib/python2.5/site-packages/virtinst/ParaVirtGuest.py", line 45, in _prepare_install
  self._installer.prepare(guest = self, meter = meter)
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 678, in prepare
  self._prepare_kernel_and_initrd(guest, distro, meter)
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 648, in _prepare_kernel_and_initrd
  distro = distro)
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 578, in acquireKernel
  progresscb=progresscb, distro=distro, scratchdir=scratchdir)
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 561, in _storeForDistro
  if store.isValidStore(fetcher, progresscb):
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 213, in isValidStore
  if fetcher.hasFile("Fedora", progresscb):
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 160, in hasFile
  tmpfile = self.acquireFile(filename, progresscb)
File "/usr/lib/python2.5/site-packages/virtinst/DistroManager.py", line 150, in acquireFile
  raise ValueError, _("Invalid file location given: ") + msg
ValueError: Invalid file location given: No such file or directory
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Daniel P. Berrange wrote:

On Fri, Nov 09, 2007 at 08:42:52PM -0500, address@hidden wrote:
  

I must apologize for subscribing to this list, but the Qemu users list 
is dead, sop this is my only option.
I understand it is a development list, but I would appreciate some help.

I will make it concise.

1) What is the best Distro to run Qemu on with the least hassles?
FYI, I now run it on FC7, but it is a lot of trouble. kqemu refuses to 
work on FC7 on a v20z Sun dual cpu dual core rack server
XEN just completely doesnt load even though  the Kernel is XEN, but at 
least qemu works with the following Caveat;
"Could not open '/dev/kqemu' - QEMU acceleration layer not activated"
    

As a general rule (with a couple of exception) Fedora only ships kernel
modules which are in upstream LKML sources. kqemu is not upstream, so it
is not included in Fedora RPMs for QEMU.

  

2)  Does an activated QEMU acceleration layer (missing above)  make a 
huge difference?
    

Yes, it improves performance signficantly - although not all OS will run
under kqemu.

  

3) I have several operating systems successfully loaded in Qemu 
sessions, but networking is just not working. I worked through loads of  
FAQs from the net, but to no avail.
    

With Fedora 7 you can try  'virt-manager' which will let you setup QEMU
guests, which by default have NAT'd access to the outside world. If you
setup your host network in appropriate manner they can also be bridged
In this doc where you see 'kvm' - 'qemu' applies  just the same way

http://watzmann.net/blog/index.php/2007/04/27/networking_with_kvm_and_libvirt

The main potential gotcha I know is that ip_forward must be enabled

eg, 

$ /sbin/sysctl net.ipv4.ip_forward
net.ipv4.ip_forward = 1


  

4) Finally is there a preferred distro which is known to solve all the 
problems mentioned above?
    

Networking should work correctly for NAT & bridging (assuming suitable host
config). KQEMU won't work in Fedora since the module is not upstream.

Regards,
Dan.