Hey there, for testing purpose I try to run a Windows Server 2012 with Hyper-V in Ovirt 3.6.5 nodes and engine systems are based on Centos 7. The vdsm hook nested are also correctly installed and seems working. If I try to install the Hyper-V role, I've got the error massage that a hypervisor is already running. In the config the System is set to Windows 2012 X64. It's the same error mesage if I changed this to Windows 7 or 8 or Windows 2012 R2 x64. I found some threads in the mailarchive where people are using the same setup... Whats wrong in my setup? This is the launched process: /usr/libexec/qemu-kvm -name win-root-domain -S -machine pc-i440fx-rhel7.2.0,accel=kvm,usb=off -cpu Nehalem,+vmx -m size=4194304k,slots=16,maxmem=4294967296k -realtime mlock=off -smp 2,maxcpus=16,sockets=16,cores=1,threads=1 -numa node,nodeid=0,cpus=0-1,mem=4096 -uuid 598aab68-48bc-4a9a-ae6f-841dd6a25a7b -smbios type=1,manufacturer=oVirt,product=oVirt Node,version=7-2.1511.el7.centos.2.10,serial=33313934-3432-5A43-4339-343331594446,uuid=598aab68-48bc-4a9a-ae6f-841dd6a25a7b -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/domain-win-root-domain/monitor.sock,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=2016-05-10T08:12:10,driftfix=slew -global kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -boot strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 -device virtio-serial-pci,id=virtio-serial0,max_ports=16,bus=pci.0,addr=0x5 -drive file=/rhev/data-center/mnt/10.10.10.25:_volume1_ovirt/c4aa106c-1dc4-4b2c-9e94-0885c34c291a/images/11111111-1111-1111-1111-111111111111/9200.16384.WIN8_RTM.120725-1247_X64FRE_SERVER_EVAL_DE-DE-HRM_SSS_X64FREE_DE-DE_DV5.ISO,if=none,id=drive-ide0-1-0,readonly=on,format=raw,serial= -device ide-cd,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0,bootindex=2 -drive file=/rhev/data-center/00000002-0002-0002-0002-000000000228/4e61bb2c-503f-4e4d-837d-43b31b4e97cd/images/9f9543e1-3d39-468a-a67d-4b2f95d05238/dce05340-6e26-44fc-b7cb-4d5ef46d3db2,if=none,id=drive-virtio-disk0,format=raw,serial=9f9543e1-3d39-468a-a67d-4b2f95d05238,cache=none,werror=stop,rerror=stop,aio=native -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev tap,fd=31,id=hostnet0 -device e1000,netdev=hostnet0,id=net0,mac=00:1a:4a:48:28:01,bus=pci.0,addr=0x3 -chardev socket,id=charchannel0,path=/var/lib/libvirt/qemu/channels/598aab68-48bc-4a9a-ae6f-841dd6a25a7b.com.redhat.rhevm.vdsm,server,nowait -device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,id=channel0,name=com.redhat.rhevm.vdsm -chardev socket,id=charchannel1,path=/var/lib/libvirt/qemu/channels/598aab68-48bc-4a9a-ae6f-841dd6a25a7b.org.qemu.guest_agent.0,server,nowait -device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel1,id=channel1,name=org.qemu.guest_agent.0 -chardev spicevmc,id=charchannel2,name=vdagent -device virtserialport,bus=virtio-serial0.0,nr=3,chardev=charchannel2,id=channel2,name=com.redhat.spice.0 -spice port=5902,tls-port=5903,addr=10.10.10.31,x509-dir=/etc/pki/vdsm/libvirt-spice,seamless-migration=on -device qxl-vga,id=video0,ram_size=67108864,vram_size=8388608,vgamem_mb=16,bus=pci.0,addr=0x2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 -msg timestamp=on Thanks for any idea. Best greetings Marco