Comment 2 for bug 448674

Hosts:
CPU: Intel(R) Core(TM)2 CPU 6300 @ 1.86GHz
RAM: 2GB
Disk: Gbit NFS-mount on NetApp FAS3040 (/etc/libvirt/qemu)
10.0.40.100:/vol/hl/disk_images /etc/libvirt/qemu/disks nfs rsize=32768,wsize=32768,hard,intr,tcp,timeo=600,rw 0 0

Installed both hosts with Ubuntu Jaunty 9.04.
aptitude install libvirt-bin qemu kvm host sysstat iptraf iptables portmap nfs-common realpath bridge-utils vlan ubuntu-virt-server python-vm-builder whois postfix hdparm

After some testing with migration (all failed because of several errors/bugs) I upgraded to Ubuntu Karmic 9.10 Beta.

cat /etc/network/interfaces:
auto lo
iface lo inet loopback

auto eth1
iface eth1 inet manual
        up ifconfig eth1 0.0.0.0 up
        up ip link set eth1 promisc on

auto eth1.1503
iface eth1.1503 inet manual
        up ifconfig eth1.1503 0.0.0.0 up
        up ip link set eth1.1503 promisc on

auto br_extern
iface br_extern inet static
        address 123.123.32.252 # HOSTA
        address 123.123.32.253 # HOSTB
        network 123.123.32.0
        netmask 255.255.252.0
        broadcast 123.123.35.255
        gateway 123.123.32.1
        bridge_ports eth0.1503
        bridge_stp off

/etc/resolv.conf is correct
/etc/hosts is correct
Hostnames are correct and resolvable

VM running Ubuntu Jaunty 9.04:
fqdn.com.xml:
<?xml version="1.0"?>
<domain type="kvm">
  <name>fqdn.com</name>
  <uuid>70a1c1f2-9a3e-4ee5-9f95-69e7e2682e15</uuid>
  <memory>1048576</memory>
  <currentMemory>1048576</currentMemory>
  <vcpu>1</vcpu>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <os>
    <type>hvm</type>
    <boot dev="cdrom"/>
    <boot dev="hd"/>
  </os>
  <clock offset="utc"/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/bin/kvm</emulator>
    <disk type="file" device="disk">
      <source file="/etc/libvirt/qemu/disks/1378/fqdn.com/disk0.qcow2"/>
      <target dev="hda" bus="ide"/>
      <driver cache="writethrough"/>
    </disk>
    <interface type="bridge">
      <mac address="56:16:43:76:ab:09"/>
      <source bridge="br_extern"/>
    </interface>
    <disk type="file" device="cdrom">
      <target dev="hdc" bus="ide"/>
      <readonly/>
    </disk>
    <input type="mouse" bus="ps2"/>
    <graphics type="vnc" port="-1" listen="127.0.0.1"/>
  </devices>
</domain>

Define instance:
/usr/bin/virsh define /etc/libvirt/qemu/xml/1378/fqdn.com.xml

Start instance:
/usr/bin/virsh start fqdn.com

ps auxf | grep kvm:
/usr/bin/kvm -S -M pc-0.11 -m 1024 -smp 1 -name fqdn.com -uuid 70a1c1f2-9a3e-4ee5-9f95-69e7e2682e15 -monitor unix:/var/run/libvirt/qemu/fqdn.com.monitor,server,nowait -boot dc -
drive file=/etc/libvirt/qemu/disks/1378/fqdn.com/disk0.qcow2,if=ide,index=0,boot=on -drive file=,if=ide,media=cdrom,index=2 -net nic,macaddr=56:16:43:76:ab:09,vlan=0,name=nic.0 -net tap,fd=17,vlan=0
,name=tap.0 -serial none -parallel none -usb -vnc 127.0.0.1:0 -vga cirrus

Migrate instance:
/usr/bin/virsh migrate fqdn.com qemu+ssh://hostb.fqdn.com/system

Migration will complete but the instance seems to be suspended.
On HostB to resume the instance:
/usr/bin/virsh suspend fqdn.com
/usr/bin/virsh resume fqdn.com

Only running resume fqdn.com does nothing.

The Hosts were initialy installed as Ubuntu Jaunty 9.04 and upgraded to Ubuntu Karmic 9.10 Beta. Maybe this is the problem?