[libvirt] virsh -no-kvm problem on debian install

22 Jun 2009

      Hi,

i've installed lastest kvm-86 and libvirt-0.6.4 tarballs on my debian 
stable and have a problem using virsh

No matter what i do in the guest domain config or with /usr/bin/ 
symlinks, libvirt keeps using the -no-kvm option when starting guests 
when my cpu has kvm-amd support, modules are loaded and /dev/kvm exists, 
and starting the guests thru command line works fine, and faster.

debian seems to install the following binary 
/usr/bin/qemu-system-x86_64, i had to add "/usr/bin/qemu" to get virsh 
to work, otherwise it will say it can't connect to qemu:///system

here's some command output :

#virsh -c qemu:///system capabilities

<capabilities>

  <host>
    <cpu>
      <arch>x86_64</arch>
    </cpu>
    <migration_features>
      <live/>
      <uri_transports>
        <uri_transport>tcp</uri_transport>
      </uri_transports>
    </migration_features>
  </host>

  <guest>
    <os_type>hvm</os_type>
    <arch name='i686'>
      <wordsize>32</wordsize>
      <emulator>/usr/bin/qemu</emulator>
      <machine>pc</machine>
      <machine>isapc</machine>
      <domain type='qemu'>
      </domain>
    </arch>
    <features>
      <pae/>
      <nonpae/>
      <acpi default='on' toggle='yes'/>
      <apic default='on' toggle='no'/>
    </features>
  </guest>

  <guest>
    <os_type>hvm</os_type>
    <arch name='x86_64'>
      <wordsize>64</wordsize>
      <emulator>/usr/bin/qemu-system-x86_64</emulator>
      <machine>pc</machine>
      <machine>isapc</machine>
      <domain type='qemu'>
      </domain>
    </arch>
    <features>
      <acpi default='on' toggle='yes'/>
      <apic default='on' toggle='no'/>
    </features>
  </guest>

</capabilities>

and tried adding "/usr/bin/qemu-kvm" symlink

<capabilities>

  <host>
    <cpu>
      <arch>x86_64</arch>
    </cpu>
    <migration_features>
      <live/>
      <uri_transports>
        <uri_transport>tcp</uri_transport>
      </uri_transports>
    </migration_features>
  </host>

  <guest>
    <os_type>hvm</os_type>
    <arch name='i686'>
      <wordsize>32</wordsize>
      <emulator>/usr/bin/qemu</emulator>
      <machine>pc</machine>
      <machine>isapc</machine>
      <domain type='qemu'>
      </domain>
      <domain type='kvm'>
        <emulator>/usr/bin/qemu-kvm</emulator>
      </domain>
    </arch>
    <features>
      <pae/>
      <nonpae/>
      <acpi default='on' toggle='yes'/>
      <apic default='on' toggle='no'/>
    </features>
  </guest>

  <guest>
    <os_type>hvm</os_type>
    <arch name='x86_64'>
      <wordsize>64</wordsize>
      <emulator>/usr/bin/qemu-system-x86_64</emulator>
      <machine>pc</machine>
      <machine>isapc</machine>
      <domain type='qemu'>
      </domain>
      <domain type='kvm'>
        <emulator>/usr/bin/qemu-kvm</emulator>
      </domain>
    </arch>
    <features>
      <acpi default='on' toggle='yes'/>
      <apic default='on' toggle='no'/>
    </features>
  </guest>

</capabilities>

So far i had no luck getting virsh to use kvm, it always adds the 
-no-kvm option, i'm not sure how to specify the domain type in the guest 
config, using the <emulator>/usr/bin/qemu-kvm</emulator> won't help.

i've found that thread discussing the binaries and options but don't 
know if that patch was already added or if i have to patch my tarball..

http://www.redhat.com/archives/libvir-list/2009-March/msg00281.html

please let me know if there's some way to let libvirt know that kvm 
exists on a debian install, using /usr/bin/qemu-system-x86_64

thx,

Marc

[libvirt] virsh -no-kvm problem on debian install

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