• Proxmox Breaks Storage/LVM Backing If Killing QEMU-IMG


    I tried to stop a qemu-img copy or clone and it broke everything. It was fine to "stop" it from the GUI but a process still persisted so I killed the relevant qemu-img and the kernel went crazy. It also may not have helped that I tried to lvremove a different volume (an unused disk). But either way it breaks LVM (you cannot even run lvdisplay) so a reboot is necessary. Jan 17 06:45:21 testserver kernel: [ 5680.439337] systemd-udevd D 0&nbs........
  • Proxmox trying to acquire lock... TASK ERROR: can't lock file '/var/lock/qemu-server/lock-102.conf' - got timeout


    If Proxmox won't start aVM with an error like this: trying to acquire lock... TASK ERROR: can't lock file '/var/lock/qemu-server/lock-102.conf' - got timeout rm /var/lock/qemu-server/lock-102.conf Then try to restart the VM and it should be good.........
  • QEMU / KVM How To Manually Create Basic Virtual Machine VM


    1.) Create Image using qemu-img qemu-img create -f qcow2 skype.img 40G 2.) Start VM using flags -m = memory in MB -drive file=yourimagefile.img -cdrom /path/to/the.iso qemu-system-x86_64 -m 4096 -drive file=skype.img -cdrom ~/Downloads/SfB-E-9319.0-enUS.ISO ........
  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install hwloc-nox Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • qemu-img resize howto


    The Correct Way To Resize In Place qemu-img resize kvmuserwindows2008dcetest.img +1G Image resized. Below is a common mistake that some users make they are trying to specify a new image name but it can be resized in place (just make sure the VMis NOT running and you've backed up the data in case something goes wrong). qemu-img resize kvmuser453111.img kvmuser453111-larger.img +5G New i........
  • How to qemu-kvm enable bridged networking in Debian Ubuntu Linux Mint on KVM containers


    I've read a few guides about this but they didn't work for me. sudo apt-get install bridge-utils #don't think the above is enough it won't work still even though you have by default an /etc/qemu-ifup that handles it if you have the right tools and setup sudo qemu-system-x86_64 -net tap -net nic -enable-kvm -cpu host,vmx=on ~/VirtualBox VMs/vsphere-vcenter/vsphere-vcenter.vdi W: /etc/qemu-ifup: no bridge for guest interface foun........
  • VirtualBox Nested Virtual Machine Containers with KVM Not Working no SVM or VMX module in the guest


    I can't get vmx cpu extensions to show up in Virtualbox guests despite enabling nested paging and enable vmx in virtualbox guest but this doesn't help that you check VT-X or the AMD Virtualization SVM it enables it for the guest to use BUT does not pass it through. This means if you check cat /proc/cpuinfo in the guest you will see the CPUdoesn't support virtualization. It looks like VirtualBox still hasn't implemented this! But there is good news I&n........
  • PYCURL ERROR 22 - The requested URL returned error: 404 Not Found Solution


    # yum -y install qemu-kvm Loaded plugins: fastestmirror Setting up Install Process Loading mirror speeds from cached hostfile * base: mirror.lzu.edu.cn * elrepo: ftp.utexas.edu * epel: ftp.jaist.ac.jp * extras: mirrors.aliyun.com * openvz-kernel-rhel6: mirror.fdcservers.net * openvz-utils: mirror.fdcservers.net * updates: mirrors.nwsuaf.edu.cn Resolving Dependencies........
  • KVM/QEMU how to boot from direct kernel vmlinuz and initrd with networking


    Thsi is very handy when doing your own kernel development. -m specifies how much ram (in the example it is 768MB) -kernel specifies the path to the kernel file -net tap,ifname=tap1,script=no (the ifname=tap1 is what you need to change and setup manually). *Run "tunctl -b" to create a tap device and use the one it gives you for ifname= Enable networking to the outside like this: *Note we assume that your bridge is br0 i........
  • libguestfs tools howto guide for managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images To mount a partition #mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount" guestmount -a kvmuser102821.img -m /dev/sda1 mount To list partition info on the image: virt-df image.img Filesystem........
  • kvm centos cannot compile error


    ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install gcc make ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install compat-gcc-* ./configure Error: Could not find alsa Make sure to have the alsa libs and headers installed. yum -y install alsa-lib-devel ./configure........
  • qemu-img KVM create disk image howto


    qemu-img create -f qcow2 isotest.qcow2 10G The above creates a "qcow2" format image called "isotest.qcow2" that is 10GB in size.........
  • KVM support Ubuntu 12.04 or 12.10


    This seems to be a verified bug on KVM with no solution. I wasn't able to get through the installer with Ubuntu 12.04, it would crash while "configuring apt". I was able to install it with Ubuntu 12.10 but it crashes randomly at times. This happens with the latest Centos 6.3 kernel and KVM package, I even compiled the latest version from the KVM website and used that, but the results are still the same. Here's some links to discussion about the bugs:........
  • How to convert raw,img,vdi,vmdk and other virtual image formats using qemu-img convert between VBOX/KVM/VMWare/Xen


    The example below converts youvm.img into a vdi. The -O vdi specifies the new format will be vdi but you can use any other valid formats/vice versa. qemu-img convert yourvm.img -O vdi yourvm.vdi This is very handy for those who need to switch between virtualization technologies.........
  • KVM compilation issue/solution - Disabling PIE due to missing toolchain support glib-2.12 required to compile QEMU


    qemu-kvm-1.2.0]# ./configure Disabling PIE due to missing toolchain support glib-2.12 required to compile QEMU Solution install glib2 *Don't confuse glib2 with glibc, they are different and it may catch some off guard. yum -y install glib2* After that KVM should compile and install just fine.........
  • KVM/QEMU Base/Template Images and the power they provide


    qemu-img create -b centos.5-8.x86.20120308.qcow2 -f qcow2 ../kvmguests/25000-centos5.8x86.qcow2 Formatting '../kvmguests/25000-centos5.8x86.qcow2', fmt=qcow2, backing_file=centos.5-8.x86.20120308.qcow2, size=10485760 kB -b the source/base image -f format is qcow2 and the location of the destination image What is so special about this? It's even quicker than creating a template with OpenVZ but this is an actual OS. It saves time a........
  • Slow KVM Virtual Machine Performance Solved - Choose the right architecture with the CPU flag


    I am running a 64-bit host and was running a 32-bit XPguest which was crawling no matter what I was doing with it,in fact it frequently used 100% CPU power while having no real work load. I experienced with this other guests and wondered why KVM was slow compared to say Xen or Virtualbox. This is because you need to use the "-cpu" flag. For a full list of options run: /usr/libexec/qemu-kvm -cpu ? x86 ........
  • VirtualBox Convert Import/Boot .vmdk VMWare Hard Disk/Drive Image Won't Work


    I wanted to Import/Use a .vmdk hard disk image file from VMWare. Generally you can just "point" VirtualBox to it and use it and it will work but I found an exception. One of my Centos 4.4 x64 images wouldn't boot. I had two copies, an older one and the newer one. The older one booted as normal (once I changed the VirtualBox driver to IDE from SATA). The newer one stopped at the "GRUB loading" message no matter what I tried. As far as........
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