kvm / libvirt vm not reachable

["Georg Damm" <Georg.Damm@freenet.de>]

Hi all,

after installing debian wheezy I'm running a clonezilla virtual 
machine to clone some computer harddrives. Unfortunately the
data transfer breaks during the backup and the restore process
and it's not possible to connect to the VM over ssh or with a vnc 
client. I tried all the virtual network cards and the only 
improvement seems to be a _change_ of the nic after a shutdown.
However, this only delays the vm not reachable state.
Is there a way to locate the error? 
I cannot find anything suspicious in the logs of the server or the 
vm. I experienced the same behaviour in lenny 32bit environment. Is 
there a way to isolate the problem?

Georg

HOST:
---------
root@wilson:~# uname -a
Linux wilson 3.0.0-1-amd64 #1 SMP Sat Aug 27 16:21:11 UTC 2011 
x86_64 GNU/Linux

root@wilson:~# dpkg -l | grep libvirt
ii  libvirt-bin                        0.9.4-2                  
        programs for the libvirt library
ii  libvirt0                           0.9.4-2                        
  library for interfacing with different virtualization systems
ii  python-libvirt                     0.9.4-2 
                         libvirt Python bindings

root@wilson:~# virsh dumpxml clonezilla
<domain type='qemu' id='18'>
  <name>clonezilla</name>
  <uuid>.....</uuid>
  <memory>2890752</memory>
  <currentMemory>2656256</currentMemory>
  <vcpu>4</vcpu>
  <os>
    <type arch='i686' machine='pc-0.14'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <apic/>
    <pae/>
  </features>
  <cpu match='exact'>
    <model>Westmere</model>
    <vendor>Intel</vendor>
    <feature policy='require' name='tm2'/>
    <feature policy='require' name='est'/>
    <feature policy='require' name='monitor'/>
    <feature policy='require' name='ss'/>
    <feature policy='require' name='vme'/>
    <feature policy='require' name='rdtscp'/>
    <feature policy='require' name='ht'/>
    <feature policy='require' name='ds'/>
    <feature policy='require' name='pbe'/>
    <feature policy='require' name='tm'/>
    <feature policy='require' name='vmx'/>
    <feature policy='require' name='ds_cpl'/>
    <feature policy='require' name='xtpr'/>
    <feature policy='require' name='acpi'/>
    <feature policy='require' name='x2apic'/>
  </cpu>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/bin/qemu</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads'/>
      <source file='/vm/clonezilla.img'/>
      <target dev='hda' bus='ide'/>
      <alias name='ide0-0-0'/>
      <address type='drive' controller='0' bus='0' unit='0'/>
    </disk>
    <disk type='block' device='disk'>
      <driver name='qemu' type='raw' cache='none' io='threads'/>
      <source dev='/dev/vg_wilson/vm_clonezilla_dir_backup'/>
      <target dev='hdb' bus='ide'/>
      <alias name='ide0-0-1'/>
      <address type='drive' controller='0' bus='0' unit='1'/>
    </disk>
    <controller type='ide' index='0'>
      <alias name='ide0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' 
function='0x1'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <alias name='virtio-serial0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x08' 
function='0x0'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:00:c5:bd:35'/>
      <source bridge='intern'/>
      <target dev='vnet0'/>
      <model type='e1000'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' 
function='0x0'/>
    </interface>
    <interface type='bridge'>
      <mac address='52:54:00:9c:7f:45'/>
      <source bridge='brclone'/>
      <target dev='vnet1'/>
      <model type='e1000'/>
      <alias name='net1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' 
function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/0'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <serial type='pty'>
      <source path='/dev/pts/2'/>
      <target port='1'/>
      <alias name='serial1'/>
    </serial>
    <console type='pty' tty='/dev/pts/0'>
      <source path='/dev/pts/0'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <input type='tablet' bus='usb'>
      <alias name='input0'/>
    </input>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5900' autoport='yes'/>
    <sound model='ich6'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' 
function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' 
function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' 
function='0x0'/>
    </memballoon>
  </devices>
</domain>

GAST:---------
Debian squeeze 32 bit