/ - rtt - IT Resource

  • 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........
  • How To Enable Nested KVM so guests can virtualize with hardware extensions


    #check if nested KVM is enabled by doing a cat on nested inside sys root@s14:~# cat /sys/module/kvm_intel/parameters/nested  root@s14:~# echo "options kvm-intel nested=Y" > /etc/modprobe.d/kvm-intel.conf root@s14:~# echo "options kvm-amd nested=1" > /etc/modprobe.d/kvm-amd.conf root@s14:~# modprobe -r kvm_intel modprobe: FATAL: Module kvm_intel is in use. root@s14:~# modprob........
  • Supermicro IPMI / KVM / BMC Remote Console Screen Resizing Issue - Window Cut Off Solution


    It could just be my specific Java but other KVM/IP works ok on my machine but with Supermicro's IPMI for some reason the console window doesn't resize and even putting it in full screen leaves the window cut off as shown below: As you can see above the screen is cut off you can't see the "I agree" on the right side. The window resi........
  • 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 VM is 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 CPU doesn't support virtualization.  It looks like VirtualBox still hasn't implemented this! But there is good news I&n........
  • OVF Tool: Error: Task failed on server: This host does not support Intel VT-x. VMWare VCenter install On ESXi ERror


    Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled: cat /sys/module/kvm_intel/parameters/nested Y cat /sys/module/kvm_intel/parameters/ept Y     OVF Tool: Disk progress: 99% OVF Tool: Transfer Completed OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance- OVF Tool: Task p........
  • cannot mount kvm ntfs image


    guestmount -a kvmuserscra.img -m /dev/sda1 mount libguestfs: error: mount_options: /dev/sda1 on / (options: ''): mount: unknown filesystem type 'ntfs' guestmount: '/dev/sda1' could not be mounted. guestmount: Did you mean to mount one of these filesystems? guestmount:     /dev/sda1 (ntfs) guestmount:     /dev/sda2 (ntfs) yum -y install ntfs-3g still........
  • /usr/bin/supermin-helper exited with error status 1. To see full error messages you may need to enable debugging. See http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs at /usr/bin/virt-list-partitions line 177.


     virt-list-partitions kvmusertest.img /usr/bin/supermin-helper exited with error status 1. To see full error messages you may need to enable debugging. See http://libguestfs.org/guestfs-faq.1.html#debugging-libguestfs at /usr/bin/virt-list-partitions line 177. #solution update-guestfs-appliance........
  • Disable SSH Password Authentication to Increase Security and Harden SSH Linux Unix Server Ubuntu Mint Centos Debian


    Just a note before you do this you should have a sure, guaranteed way into the system such as local, KVM or preferably publickey making bruteforce SSH absolutely impossible since there is no password to bruteforce and even if someone knew the password they wouldn't be able to login except from the local console (presumably you should make sure no one unauthorized has physical access). 1. Edit /etc/ssh/sshd_config Find the section like this:........
  • Centos 6.6/6.9 KVM VM Kernel Panic On Boot - Kernel panic - not syncing: Attempted to kill init!


    I am not sure why this is happening neither the hostnode or VM changed.  All I did was reboot the hostnode and startup the Centos VM again, also note it happened with the original kernel on the VM and also the latest 6.9 kernel as of this writing as shown below. Host Node: Centos 6.9 Kernel: 2.6.32-696.6.3.el6.x86_64  Kernel: 2.6.32-042stab123.9 Same result in any kernel above........
  • cudaminer freezes Linux Mint taints kernel


    When running cudaminer once it tries to initialize the card the entire screen freezes.  The computer itself is still running but the Xorg is done for, you cannot even switch to another console window and must reboot (even an mdm or Xorg restart does not help). At first cudaminer will give you these errors: stratrum_recv_line failed ...retry after 15 seconds GPU #0: Geforce 210 with compute ca........
  • Avocent DSR8020 KVM/IP - Network Connect Error - Solution


    This error is commonly due to Java security or TLS settings but there is a second issue with forwarded ports that also causes it.   1. Java Security/TLS Settings issue: This article has the solution to change them all in Linux automatically 2. Port Forwarding Issue if your Avocent DSR is behind NAT/private IP........
  • 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........
  • Avocent 8020 KVM Java Icedtea Viewer


    It seems every other updated version of Java or Icedtea breaks things and I will save the frustration of Java for another post. *If you get the icedteaweb window but nothing loads or prompts it is probably your security settings that won't even prompt to run it.   See this article to solve that problem. To fix this error you need to edit the java.security file m........
  • Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling


    Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason.  Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to?  In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........
  • Windows 2012 Server R2 Install Error "windows cannot find the microsoft license terms windows 2012 server install"


    windows cannot find the microsoft license terms windows 2012 server install This is actually because you are using less than 576MB of RAM.  In my case I was installing on a KVM VPS with 512MB of RAM.  This issue would apply to any physical or virtual server with less than 576MB of RAM.  This includes Virtualized VPS Servers with XEN HVM, KVM, VBOX, VMWare etc.. or Dedicated Servers with such little RAM. It's very misleading of course since it has not........
  • kvm how to add secondary cdrom drive


    This is useful if you are installing Windows and need virtio but of course Windows needs the virtio driver which is on a second iso. This is the line of code you would add to your kvm startup script and then you get this iso as  second cdrom you can browse to for your Windows install of virtio driver's or whatever other use you need it for. -drive file=/kvmtemplates/virtio-win-0.1-94.iso,media=cdrom........
  • 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........
  • How to install grub on virtio KVM with Linux


    I messed up the bootloader by accident on a standard Centos 6.3 install because I turned the /dev/vda1 boot partition into an mdadm raid 1.  This was all done correctly aside from one point I didn't realize was an issue metadata=00.90 is the only thing that will allow you to boot (otherwise grub won't work and you won't boot). So the next step is rescue mode from a CD right? The problem you will find is that grub does not detect your hard drives, this is I believe is be........
  • KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 solution


    If the below is happening on KVM (a very weird and scary looking error) it's probably because of Windows. This has happened countless times to me where the bootsector on Windows 7/2008 becomes corrupted easily (even by a crash or shutdown).  KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 rax 0000000000000010 rbx 0000000000000080 rcx 0000000000000000 rdx 0000000000000080 rsi 000000000025db2a rdi 000000000007db2a rsp 0000000000000200 rbp........
  • 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          ........
  • SolusVM error error: Failed to create domain from /home/kvm/kvm101/kvm101.xml error: cannot open file '/dev//dev/kvmcontainer/kvm101_img': No such file or directory


    error: Failed to create domain from /home/kvm/kvm101/kvm101.xml error: cannot open file '/dev//dev/kvmcontainer/kvm101_img': No such file or directory This is caused by what we consider a quark in SolusVM that I helped a client with. SolusVM has as config for the "LVM volume name" and does not enforce any convention. Naturally most technical people would use the actual path eg "/dev/kvmcontainer". However th........
  • OpenVZ avoid vzctl 4.7 and ploop


    <p>OpenVZ has made vzctl version 4.7 default to using ploop which is a big annoyance.&nbsp; No one wants it otherwise we'd use Xen or KVM.</p> <p>Make sure to manually specify vzctl 4.6.1 or you will have issues with old scripts breaking since it defaults to using ploop (a single image like Xen/KVM).</p> <p><a href="https://openvz.org/Download/vzctl/Archives">Here's a list to old versions of vzctl.</a></p>........
  • LVM Tutorial how to create a Physical Volume (PV), Volume Group (vg), and a Logical Volume (LV) within it


    # first we need a physical volume which we use the pvcreate tool to create # I create mine on /dev/sdb3 pvcreate /dev/sdb3   dev_is_mpath: failed to get device for 8:19   Physical volume "/dev/sdb3" successfully created # pvdisplay shows the newly created volume pvdisplay   "/dev/sdb3" is a new physical volume of "1.35 TiB"   --- NEW Physical volume ---   PV N........
  • Howto Convert Xen Image to KVM


    #count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if=<xenimage> of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........
  • virtio KVM drivers download location


    http://realtechtalk.com/downloads/virtio-win-0.1-74.iso Current Direct stable URL from Fedora: https://fedoraproject.org/wiki/Windows_Virtio_Drivers Direct Downoad of Stable Virtio: https://fedorap........
  • lvm how to resize and extend a volume


    lvextend -L +10G /dev/kvmvm/w2k8r2evalstandard   Extending logical volume w2k8r2evalstandard to 20.00 GiB   Logical volume w2k8r2evalstandard successfully resized The above adds 10GB to the logical volume.  Of course you must resize the filesystem using other tools to take advantage of the space.........
  • 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........
  • KVM on Centos 6.3 cannot boot FreeBSD 9.2 AMD64


    <p>On the same OS with the same kernels basically I cannot boot FreeBSD installer, I&nbsp;believe the issue is the host CPU.</p> <p>One host runs an Intel and works, while an Opteron 2373 does not work despite suggestions from this thread: <a href="http://149.20.54.209/showthread.php?t=36761">http://149.20.54.209/showthread.php?t=36761</a></p> <p>I've tried cpu options like &quot;kvm64&quot; &quot;Opteron_G3&quot; and none........
  • open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted - Solution


    open /dev/kvm: No such file or directory failed to initialize KVM: Operation not permitted [   96.084502] kvm: disabled by bios Any of the above means that "Virtualization" is not enabled in your BIOS.  Most servers and Desktops (non-mainstream) can do this no problem but leave it off by default.  Note that some systems even though the CPU supports it, don't allow enabling of Virtualization for some reason (especially some lap........
  • 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 Guest Network Not Working Can't Ping ETC Solution


    Once I set a new MAC address everything was fine and finally anything can be pinged etc.., I've had this happen with many clients in different datacenters on different hardware.........
  • 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:........
  • kvm cannot boot xen guest using lvm


    This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........
  • 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.........
  • Startech SV1107IPEXT KVM/IP Review


    Let's keep this simple, it's horrible, not only is the picture quality horrible (it's not a big deal) but the keyboard input is an issue.  You have to type slowly, lightly and carefully otherwise 1-keystroke could end up being dozens of keystrokes. It's also a confusing unit for many datacenter techs, I've seen these units hooked up wrong and the instructions themselves aren't clear.  I had to resort to shipping one to my office and take my phone pictures of the setup for th........
  • Lantronix KVM/IP Keyboard/Mouse not working in BIOS before booting the OS


    I've run into two issues with Lantronix based KVMs on various servers and here's how I solved them (with that said I like these units as they are Java based and OS independent and work very well, unike some other models like Startech). 1.) If you are connected by USB only and you're sure USB support from the BIOS is enabled, you just need to click the following in Lantronix Interfaces -> Keyboard/Mouse Check "Force USB Full Speed Mode", this fixed the issu........
  • 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 Windows 7 won't boot Virtual Machine/VM after install solution


    This seems to be common for some reason when trying to run Windows 7 under KVM and 7 has always had strange issues with KVM.  What happens for me is after the install it simply won't boot, it stays on the POST screen and does nothing. For some reason it appears the boot sector either doesn't get installed or gets corrupted with KVM. The solution is to boot the install disc for Windows 7 and reinstall the windows MBR into the boot sector: 1. Boot t........
  • 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 XP guest 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 - Failed to open a session for the virtual machine XP. AMD-V is being used by another hypervisor. (VERR_SVM_IN_USE). - Solution


    Failed to open a session for the virtual machine XP. AMD-V is being used by another hypervisor. (VERR_SVM_IN_USE). VirtualBox can't enable the AMD-V extension. Please disable the KVM kernel extension, recompile your kernel and reboot (VERR_SVM_IN_USE) Solution - Unload KVM module (you can't use two hardware virtualization suites at once) sudo rmmod kvm_amd kvm........
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