Hi, Please let me know in case I am posting my question to the wrong forum. I apologize if that is the case! Here is my question: We run CentOS 6.3 on a server with dual Xeon CPU's. Our "dual blade" server uses this motherboard: http://www.supermicro.com/products/motherboard/Xeon/C600/X9DRT-HF.cfm We have two of these CPUs installed and working: Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz ( http://ark.intel.com/products/64594/Intel-Xeon-Processor-E5-2620-15M-Cache-2_00-GHz-7_20-GTs-Intel-QPI ) cat /proc/cpuinfo correctly reports a total of 24 cores (2 x 6 phisycal cores plus 2 x 6 hyperthreading cores) However, I get this output from virsh nodeinfo : # virsh nodeinfo CPU model: x86_64 CPU(s): 24 CPU frequency: 2000 MHz CPU socket(s): 1 Core(s) per socket: 6 Thread(s) per core: 2 NUMA cell(s): 2 Memory size: 16303552 kB As you can see, virsh nodeinfo reports only 1 CPU socket while in fact we have two CPU's. I would like to know if this is normal? Why does virsh reports only one physical CPU ?? Also, when we try to run a guest OS (Debian Linux "squeeze") with more than 4 vcpu's assigned to the VM, the guest OS won't boot up. The guest's kernel stuck on a screen right after it detected the /dev/vda block device and its partitions. We're using the VirtIO driver, of course. If I assign only 4 (or less) vcpu's to the guest OS it works fine. I have tried to upgrade the Linux kernel on the guest from debian backports, it did not help, we're experiencing the same issue with both the 2.6.32 and 3.2 Linux kernels. What could be causing this? On the host, we use the Linux kernel that came with CentOS 6.3 : 2.6.32-279.11.1.el6.x86_64 #1 SMP Tue Oct 16 15:57:10 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux Thanks, Zoltan
bertrand.louargant at atoutlinux.net
2012-Oct-24 15:58 UTC
[CentOS-virt] KVM + virsh nodeinfo + CentOS 6.3
Hello, You have a NUMA (Non Uniform Memory Access) machine, which mean that each processor has its own memory controller. virsh nodeinfo give you 2 NUMA cells with 1 CPU socket each: 2 NUMA cells x 1CPU socket x 6 Core(s) per socket x 2 threads per core = 24 "cores". The NUMA concept is really important, especially in virtualization. If you have a virtual machine with vCPUs spread across more than one NUMA cell, performances will drop drastically. Maybe you cannot assign more than 4 cPUs to your VM because Libvirt cannot pin them all on the same NUMA cell ... You can try to specify the NUMA architecture in the xml config. Br, Bertrand. Le 24 octobre 2012 ? 17:14, Zoltan Frombach <zoltan at frombach.com> a ?crit :> Hi, > > Please let me know in case I am posting my question to the wrong forum. > I apologize if that is the case! > > Here is my question: > > We run CentOS 6.3 on a server with dual Xeon CPU's. Our "dual blade" > server uses this motherboard: > http://www.supermicro.com/products/motherboard/Xeon/C600/X9DRT-HF.cfm > > We have two of these CPUs installed and working: > Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz > ( > http://ark.intel.com/products/64594/Intel-Xeon-Processor-E5-2620-15M-Cache-2_00-GHz-7_20-GTs-Intel-QPI > ) > > cat /proc/cpuinfo correctly reports a total of 24 cores (2 x 6 phisycal > cores plus 2 x 6 hyperthreading cores) > > However, I get this output from virsh nodeinfo : > > # virsh nodeinfo > CPU model: x86_64 > CPU(s): 24 > CPU frequency: 2000 MHz > CPU socket(s): 1 > Core(s) per socket: 6 > Thread(s) per core: 2 > NUMA cell(s): 2 > Memory size: 16303552 kB > > As you can see, virsh nodeinfo reports only 1 CPU socket while in fact > we have two CPU's. > > I would like to know if this is normal? Why does virsh reports only one > physical CPU ?? > > Also, when we try to run a guest OS (Debian Linux "squeeze") with more > than 4 vcpu's assigned to the VM, the guest OS won't boot up. The > guest's kernel stuck on a screen right after it detected the /dev/vda > block device and its partitions. We're using the VirtIO driver, of > course. If I assign only 4 (or less) vcpu's to the guest OS it works > fine. I have tried to upgrade the Linux kernel on the guest from debian > backports, it did not help, we're experiencing the same issue with both > the 2.6.32 and 3.2 Linux kernels. What could be causing this? > > On the host, we use the Linux kernel that came with CentOS 6.3 : > 2.6.32-279.11.1.el6.x86_64 #1 SMP Tue Oct 16 15:57:10 UTC 2012 x86_64 > x86_64 x86_64 GNU/Linux > > Thanks, > > Zoltan > _______________________________________________ > CentOS-virt mailing list > CentOS-virt at centos.org > http://lists.centos.org/mailman/listinfo/centos-virt-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20121024/fd26cd69/attachment-0006.html>
Zoltan Frombach
2012-Oct-24 21:47 UTC
[CentOS-virt] CentOS 6.3 kvm-qemu problem with Debian guest
Hello, I have CentOS 6.3 installed on a server with dual Xeon CPU's. Motherboard info: http://www.supermicro.com/products/motherboard/Xeon/C600/X9DRT-HF.cfm CPU info (we have two of these): Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz http://ark.intel.com/products/64594/Intel-Xeon-Processor-E5-2620-15M-Cache-2_00-GHz-7_20-GTs-Intel-QPI Generally kvm-qemu works. But, my Debian guest OS (Debian "squeeze" with 2.6.32 Linux kernel) won't boot up if I assign more than 4 vcpus to the guest. What happens is, the kernel starts to load then it freezes right where it should load the Linux agpgart module. It just hangs there. I can hit enter in the console and the cursor moves down but that's all what I can do besides force-shutoff the guest vm. If I change the VM's config to have just 4 vcpus then it boots up most of the time! Sometimes it hangs with just 4 vcpus, too. When it hangs, it always hangs at the same point, so it is consistent. Also, changing the amount of RAM of the VM also have an effect: with 6GB or less RAM assigned to the VM it most likely boots up fine. With 8GB RAM, however, it will boot up about 50% of the time and it hangs the other 50% of the time. My Debian guest VM *never* booted up with 6 or more vcpus. Agaim, with 4 vcpus it may or may not boot up but if I add 8GB RAM regardless of the vcpu count it will more likely hang at bootup. I don't change anything else between these tries just the number of vcpus or the amount of RAM. I have tried to use a newer Debian kernel installed from Debian backports (3.2.x.x Linux kernel), but it did not help. What happens is exactly the same thing. I also have other Debian VM images (some of the raw image file based some of them LVM block device based) and I can reproduce the problem with all of them. My problem somewhat resembles this one: http://forum.parallels.com/showthread.php?t=4882 except that I'm not using parallels at all, I am trying to use kvm-qemu under CentOS 6.3 But this part seems to apply to my case: "I did experience some relief ... by changing the amount of available RAM, but that has no longer prevented the intel-agp kernel panic recently." I've tried to blacklist the agpgart module inside my guest OS to no avail. Here is what I've added to the end of /etc/modprobe.d/blacklist.conf : blacklist agpgart blacklist intel-agp However, when the VM happens to boot up then I see this entry in dmesg (snippet): Oct 25 23:27:01 infoglobal kernel: [ 0.864798] pci_hotplug: PCI Hot Plug PCI Core version: 0.5 Oct 25 23:27:01 infoglobal kernel: [ 0.865650] pciehp: PCI Express Hot Plug Controller Driver version: 0.4 Oct 25 23:27:01 infoglobal kernel: [ 0.866538] acpiphp: ACPI Hot Plug PCI Controller Driver version: 0.5 Oct 25 23:27:01 infoglobal kernel: [ 0.867484] acpiphp: Slot [1] registered Oct 25 23:27:01 infoglobal kernel: [ 0.868250] acpiphp: Slot [2] registered Oct 25 23:27:01 infoglobal kernel: [ 0.868995] acpiphp: Slot [3] registered Oct 25 23:27:01 infoglobal kernel: [ 0.869750] acpiphp: Slot [4] registered Oct 25 23:27:01 infoglobal kernel: [ 0.870489] acpiphp: Slot [5] registered Oct 25 23:27:01 infoglobal kernel: [ 0.871233] acpiphp: Slot [6] registered Oct 25 23:27:01 infoglobal kernel: [ 0.871959] acpiphp: Slot [7] registered Oct 25 23:27:01 infoglobal kernel: [ 0.872735] acpiphp: Slot [8] registered Oct 25 23:27:01 infoglobal kernel: [ 0.873472] acpiphp: Slot [9] registered Oct 25 23:27:01 infoglobal kernel: [ 0.874222] acpiphp: Slot [10] registered Oct 25 23:27:01 infoglobal kernel: [ 0.874958] acpiphp: Slot [11] registered Oct 25 23:27:01 infoglobal kernel: [ 0.875705] acpiphp: Slot [12] registered Oct 25 23:27:01 infoglobal kernel: [ 0.876494] acpiphp: Slot [13] registered Oct 25 23:27:01 infoglobal kernel: [ 0.877237] acpiphp: Slot [14] registered Oct 25 23:27:01 infoglobal kernel: [ 0.877987] acpiphp: Slot [15] registered Oct 25 23:27:01 infoglobal kernel: [ 0.878749] acpiphp: Slot [16] registered Oct 25 23:27:01 infoglobal kernel: [ 0.879517] acpiphp: Slot [17] registered Oct 25 23:27:01 infoglobal kernel: [ 0.880299] acpiphp: Slot [18] registered Oct 25 23:27:01 infoglobal kernel: [ 0.881042] acpiphp: Slot [19] registered Oct 25 23:27:01 infoglobal kernel: [ 0.881791] acpiphp: Slot [20] registered Oct 25 23:27:01 infoglobal kernel: [ 0.882546] acpiphp: Slot [21] registered Oct 25 23:27:01 infoglobal kernel: [ 0.883292] acpiphp: Slot [22] registered Oct 25 23:27:01 infoglobal kernel: [ 0.884045] acpiphp: Slot [23] registered Oct 25 23:27:01 infoglobal kernel: [ 0.884796] acpiphp: Slot [24] registered Oct 25 23:27:01 infoglobal kernel: [ 0.885545] acpiphp: Slot [25] registered Oct 25 23:27:01 infoglobal kernel: [ 0.886280] acpiphp: Slot [26] registered Oct 25 23:27:01 infoglobal kernel: [ 0.887005] acpiphp: Slot [27] registered Oct 25 23:27:01 infoglobal kernel: [ 0.887758] acpiphp: Slot [28] registered Oct 25 23:27:01 infoglobal kernel: [ 0.888539] acpiphp: Slot [29] registered Oct 25 23:27:01 infoglobal kernel: [ 0.889300] acpiphp: Slot [30] registered Oct 25 23:27:01 infoglobal kernel: [ 0.890037] acpiphp: Slot [31] registered Oct 25 23:27:01 infoglobal kernel: [ 0.891857] ERST: Table is not found! Oct 25 23:27:01 infoglobal kernel: [ 0.892590] GHES: HEST is not enabled! Oct 25 23:27:01 infoglobal kernel: [ 0.893438] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled Oct 25 23:27:01 infoglobal kernel: [ 0.916078] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A Oct 25 23:27:01 infoglobal kernel: [ 1.013996] 00:05: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A Oct 25 23:27:01 infoglobal kernel: [ 1.016342] Linux agpgart interface v0.103 Please notice the last line above: Linux agpgart interface v0.103 When the VM hangs during boot then the last line what is printed to the console is the line just above: Oct 25 23:27:01 infoglobal kernel: [ 1.013996] 00:05: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A This is why I'm suspecting that this problem have something to do with agpgart ... Anyway, here is some info about the host system: # virsh capabilities <capabilities> <host> <uuid>00020003-0004-0005-0006-000700080009</uuid> <cpu> <arch>x86_64</arch> <model>SandyBridge</model> <vendor>Intel</vendor> <topology sockets='1' cores='6' threads='2'/> <feature name='pdpe1gb'/> <feature name='osxsave'/> <feature name='tsc-deadline'/> <feature name='dca'/> <feature name='pdcm'/> <feature name='xtpr'/> <feature name='tm2'/> <feature name='est'/> <feature name='smx'/> <feature name='vmx'/> <feature name='ds_cpl'/> <feature name='monitor'/> <feature name='dtes64'/> <feature name='pbe'/> <feature name='tm'/> <feature name='ht'/> <feature name='ss'/> <feature name='acpi'/> <feature name='ds'/> <feature name='vme'/> </cpu> <power_management> <suspend_disk/> </power_management> <migration_features> <live/> <uri_transports> <uri_transport>tcp</uri_transport> </uri_transports> </migration_features> <topology> <cells num='2'> <cell id='0'> <cpus num='12'> <cpu id='0'/> <cpu id='1'/> <cpu id='2'/> <cpu id='3'/> <cpu id='4'/> <cpu id='5'/> <cpu id='12'/> <cpu id='13'/> <cpu id='14'/> <cpu id='15'/> <cpu id='16'/> <cpu id='17'/> </cpus> </cell> <cell id='1'> <cpus num='12'> <cpu id='6'/> <cpu id='7'/> <cpu id='8'/> <cpu id='9'/> <cpu id='10'/> <cpu id='11'/> <cpu id='18'/> <cpu id='19'/> <cpu id='20'/> <cpu id='21'/> <cpu id='22'/> <cpu id='23'/> </cpus> </cell> </cells> </topology> </host> <guest> <os_type>hvm</os_type> <arch name='i686'> <wordsize>32</wordsize> <emulator>/usr/libexec/qemu-kvm</emulator> <machine>rhel6.3.0</machine> <machine canonical='rhel6.3.0'>pc</machine> <machine>rhel6.2.0</machine> <machine>rhel6.1.0</machine> <machine>rhel6.0.0</machine> <machine>rhel5.5.0</machine> <machine>rhel5.4.4</machine> <machine>rhel5.4.0</machine> <domain type='qemu'> </domain> <domain type='kvm'> <emulator>/usr/libexec/qemu-kvm</emulator> </domain> </arch> <features> <cpuselection/> <deviceboot/> <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/libexec/qemu-kvm</emulator> <machine>rhel6.3.0</machine> <machine canonical='rhel6.3.0'>pc</machine> <machine>rhel6.2.0</machine> <machine>rhel6.1.0</machine> <machine>rhel6.0.0</machine> <machine>rhel5.5.0</machine> <machine>rhel5.4.4</machine> <machine>rhel5.4.0</machine> <domain type='qemu'> </domain> <domain type='kvm'> <emulator>/usr/libexec/qemu-kvm</emulator> </domain> </arch> <features> <cpuselection/> <deviceboot/> <acpi default='on' toggle='yes'/> <apic default='on' toggle='no'/> </features> </guest> </capabilities> And the entire XML config file of the Debian VM: # cat Debian-Hosting.xml <!-- WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE OVERWRITTEN AND LOST. Changes to this xml configuration should be made using: virsh edit Debian-Hosting or other application using the libvirt API. --> <domain type='kvm'> <name>Debian-Hosting</name> <uuid>b641a879-35c4-f5c5-9b9d-1a76aa843389</uuid> <memory unit='KiB'>8388608</memory> <currentMemory unit='KiB'>8388608</currentMemory> <vcpu placement='static' cpuset='6-7,18-19'>4</vcpu> <os> <type arch='x86_64' machine='rhel6.3.0'>hvm</type> <boot dev='hd'/> <bootmenu enable='no'/> </os> <features> <acpi/> <apic/> <pae/> </features> <cpu mode='custom' match='exact'> <model fallback='allow'>SandyBridge</model> <vendor>Intel</vendor> <feature policy='require' name='vme'/> <feature policy='require' name='tm2'/> <feature policy='require' name='est'/> <feature policy='require' name='vmx'/> <feature policy='require' name='osxsave'/> <feature policy='require' name='smx'/> <feature policy='require' name='ss'/> <feature policy='require' name='ds'/> <feature policy='require' name='tsc-deadline'/> <feature policy='require' name='dtes64'/> <feature policy='require' name='ht'/> <feature policy='require' name='dca'/> <feature policy='require' name='pbe'/> <feature policy='require' name='tm'/> <feature policy='require' name='pdcm'/> <feature policy='require' name='pdpe1gb'/> <feature policy='require' name='ds_cpl'/> <feature policy='require' name='xtpr'/> <feature policy='require' name='acpi'/> <feature policy='require' name='monitor'/> </cpu> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/libexec/qemu-kvm</emulator> <disk type='block' device='disk'> <driver name='qemu' type='raw' cache='none'/> <source dev='/dev/mapper/vg0_host-lv0_3_debianhost'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </disk> <controller type='ide' index='0'> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <controller type='usb' index='0'> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> </controller> <interface type='bridge'> <mac address='00:16:36:e2:20:ea'/> <source bridge='br0'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <target port='0'/> </serial> <console type='pty'> <target type='serial' port='0'/> </console> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='-1' autoport='yes'/> <video> <model type='cirrus' vram='9216' heads='1'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </memballoon> </devices> </domain> As configured above, with 8GB RAM and just 4 vcpus it just booted up - on the second attempt... If I would change the amount of RAM to 6GB it would most likely boot up almost all the time. But if I would add 2 or 4 more vcpus then it would never boot up, for sure. It always stuck at the same point, right there when the "Linux agpgart interface v0.103" should be displayed by the kernel. Any help with this would be highly appreciated! Thank you, Zoltan
Hi there, today I encountered the very same problem as described by Zoltan. We are running a system with the Intel serverboard S2600CP and two E5-2620 Xeon processors, with a total of 2 x 6 Cores with 2 threads each (resulting in a total CPU count of 24). Base system is a CentOS 6.3 with all recent updates. We are running the setup for some months now, without any problems. Most virtual machines only got 4 vCPUs, but some got 6 or 8 vCPUs. That setup was fine if running CentOS 5, CentOS 6 or Windows Server 2008 as guest systems. However, today I had to install two machines with Debian Squeeze. The first one got 4 vCPUs and runs fine, while the second one got 6 vCPUs and does not boot at all. Booting stops shortly after detecting the virtio harddisk with its partitions. When I switch back to 4 vCPUs everything is fine. Since the RHEL 5.8 and 6.3 kernels work fine, it seems to be a problem specific to the Debian kernel. Our default setup pins the different vCPUs to one fixed physical CPU each in an interleaving way. This would be the setup from /etc/libvirt/qemu/vm.xml: <memory unit='KiB'>12582912</memory> <currentMemory unit='KiB'>12582912</currentMemory> <vcpu placement='static'>6</vcpu> <cputune> <vcpupin vcpu='0' cpuset='0-5,12-17'/> <vcpupin vcpu='1' cpuset='6-11,18-23'/> <vcpupin vcpu='2' cpuset='0-5,12-17'/> <vcpupin vcpu='3' cpuset='6-11,18-23'/> <vcpupin vcpu='4' cpuset='0-5,12-17'/> <vcpupin vcpu='5' cpuset='6-11,18-23'/> </cputune> <os> <type arch='x86_64' machine='rhel6.3.0'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <pae/> </features> <cpu mode='host-model'> <model fallback='allow'/> <topology sockets='6' cores='1' threads='1'/> </cpu> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> Such a setup works fine for Redhat-kernels, but not for the Debian kernel (did only test the default 2.6.32-5 amd64 kernel so far). I played a bit with the pinning and topology, but even setting the config to do no pinning at all, and for example use 8 vCPUs divided in 2 sockets with 4 cores, or 1 socket with 8 cores or any other combination of it, does not work. The only way to get the Debian VM to boot, is to roll back to a total of 4 vCPUs (or less). As a reference, these are the cpuflags, seen from the host: processor : 23 vendor_id : GenuineIntel cpu family : 6 model : 45 model name : Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz stepping : 7 cpu MHz : 1995.156 cache size : 15360 KB physical id : 1 siblings : 12 core id : 5 cpu cores : 6 apicid : 43 initial apicid : 43 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm dca sse4_1 sse4_2 x2apic popcnt aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid bogomips : 3989.83 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: and these are the cpuflags seen from the guest: processor : 3 vendor_id : GenuineIntel cpu family : 6 model : 42 model name : Intel Xeon E312xx (Sandy Bridge) stepping : 1 cpu MHz : 1995.191 cache size : 4096 KB fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx lm constant_tsc arch_perfmon rep_good pni pclmulqdq ssse3 cx16 sse4_1 sse4_2 x2apic popcnt aes xsave avx hypervisor lahf_lm bogomips : 3990.38 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: The host is running this kernel: 2.6.32-279.11.1.el6.x86_64 #1 SMP Tue Oct 16 15:57:10 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux Packages are up to date: qemu-kvm-0.12.1.2-2.295.el6_3.2.x86_64 libvirt-0.9.10-21.el6_3.5.x86_64 The kvm commandline looks like this (for 4 vCPUs): /usr/libexec/qemu-kvm -S -M rhel6.3.0 -cpu SandyBridge,+pdpe1gb,+osxsave,+tsc-deadline,+dca,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme -enable-kvm -m 12288 -smp 4,sockets=4,cores=1,threads=1 -name xxxx -uuid xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/xxxxxxxxxxxxxx.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/dev/drbd28,if=none,id=drive-virtio-disk0,format=raw,cache=none,aio=native -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev tap,fd=22,id=hostnet0,vhost=on,vhostfd=23 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:00:xx:xx:xx,bus=pci.0,addr=0x5 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -device usb-tablet,id=input0 -vnc unix:/var/lib/libvirt/vnc/xxxxxxxxxxxxxx,password -k de -vga cirrus -incoming tcp:0.0.0.0:49152 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 Any clue on how to debug this further or how to fix is very appreciated. If any more information would be helpful, just ask. Regards, Matthias PS: please excuse if this mail is not correctly sorted into the existing thread, as I just write this after seeing the mails in the mailinglist archive without any possiblity to directly reply to the existing mails. -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 308 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20121025/347c5844/attachment-0004.sig>