KVM is the Kernel Virtual Machine, a virtualization hypervisor built into the Linux kernel.

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Sharing an X server (session) across computers

I have 2 computers (both running linux) and I'm currently using synergy to use them. This is great, but now I'm wondering, is there any way (is it possible? being worked on? tried and failed? ...
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2answers
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Weight-based block IO control for VMs

I use KVM to manage my virtual machines. I am trying to limit the resources provided for VMs. I am able to limit the CPU and memory allocated for VMs using libvirt/cgroups. Now I want to control the ...
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Faster graphics in KVM guest

Is there any way to improve the graphics performance of a KVM guest? I suspect that the question is too general, so I will give my setup and requirements. My ultimate goal is to use an Ubuntu guest ...
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7answers
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Should LVM partitions be used in virtual machine images?

Should LVM be used for the partitions when creating VM images (e.g., KVM images)? It seems like it adds complexity if you want to, say, mount a qcow2 image in the host if the image has LVM partitions. ...
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How to find the IP address of a KVM Virtual Machine, that I can SSH into it?

I have follow this guide (Virtualization With KVM On Ubuntu 11.10) to setup my KVM (Virtual Machines Software) on my Ubuntu 11.10 Server. However, I didn't setup my VM's IP address when creating the ...
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How can I restore default window size in KVM/QEMU

In KVM/QEMU machine window size by default matches guest OS resolution. But if I resize windows (accidently) how to restore default size?
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1answer
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Does QEMU/KVM use Intel AES instructions for encrypted qcow2 images if the host CPU has them?

The qcow2 image file format for KVM can use AES encryption. The encryption is applied at the cluster level: Each sector within each cluster is independently encrypted using AES Cipher Block ...
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3answers
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How to create a dupe of a KVM/libvirt/virt-manager VM?

I'm a bit lost with virt-manager / libvirt / KVM. I've got a working KVM VM (Windows XP) which works nicely. The VM is backed by a 4GB file or so (a .img). Now I want to do something very simple: I ...
6
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1answer
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Linux - LXC; deploying images with tiniest possible X11

is it currently possible to setup LXC containers with X11 capabilities? I'm looking forward for the lightest available X11 container (memory-wise), hardware acceleration a plus but not essential. If ...
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2answers
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Use virt-manager to share files between Linux host and Windows guest?

Is it possible to use "Filesystem Passthrough" virtual hardware option inside virt-manager to share a folder on my Linux host with my Windows guest? I found some tutorials for how to do this with a ...
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3answers
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How do I connect a serial terminal to a KVM instance?

Perhaps I'm misunderstanding what KVM is capable of, but the ability to add/remove hardware on the VM seems to imply I can add a serial port that then acts as a terminal. So, my questions are: ...
6
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1answer
191 views

kvm killed by oomkiller

kvm version: QEMU emulator version 1.1.2 (qemu-kvm-1.1.2+dfsg-6+deb7u3, Debian), Copyright (c) 2003-2008 Fabrice Bellard libvirtd version: libvirtd (libvirt) 0.9.12.3 debian version: 7.5 I'm running ...
6
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1answer
128 views

KVM reports strange CPU usage peaks (bash infinite recursion)

On a KVM machine running Fedora 20 I ran ulimit -s unlimited (this removes limit on stack size) and an experimental torturing testing script. All this script does is just infinite recursion: ...
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3answers
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Host CPU does not scale frequency when KVM guest needs it

I have asked this question on serverfault, but it could also have been posted here. I will synchronise the answers if one is found. Observation: I have an HP server with an AMD dual core CPU (Turion ...
5
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1answer
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QEMU-KVM and internal DHCP server

I have set up a few soon-to-be production VMs running on QEMU-KVM on Ubuntu 10.04 LTS. As for networking, I chose the "NAT" option in Virt-Manager and each VM now gets an IP address 192.168.122.x ...
5
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2answers
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How to copy qemu raw images?

I want to backup kvm virtual machines and copy machine's images another path or usb disk? How to copy " qemu raw images"?
5
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2answers
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Good tutorial for setting up a KVM/Xen box and advice on which would be better

I've got a dual xeon, 2GB, 75GB hd server that I'd like to turn into my dedicated virtual environment. Currently I'm using VirtualBox locally to run a mock cluster for Cassandra and Nginx/Haproxy, ...
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4answers
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How do I send a shutdown event to a QEMU guest (OpenBSD)?

I'm using virtualisation solely to install OpenBSD onto the bare hardware, and during the installation, the redirection to the serial port didn't get configured, so, I ended up with the system ...
5
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2answers
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GPGPU/CUDA in KVM or Xen

We would like to enable direct access to CUDA-enabled GPUs within either KVM or Xen (or Citrix Xenserver). Specifically, we want to use PCI passthrough to access an NVIDIA Tesla S2050 unit, which is ...
5
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3answers
712 views

Is it possible to run KVM over a qemu emulated powerpc architecture

I understand that qemu uses binary translation to emulate machines, so irrespective of the underlying architecture, it can provide emulation. And, KVM uses Hardware Virtualization technique to make ...
5
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1answer
477 views

Linux process scheduling - Cap/Weight based?

I am just trying to understand the basics of Linux scheduler. Is Linux scheduler a Cap based or weight based scheduler? I was previously using Xen. Now I am moving from Xen to KVM. I read VMs are ...
4
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3answers
634 views

Debian + KVM: Which version to use? Stable or “new”?

I have Debian 6.0.4 (Squeeze) x64. Nowadays I use KVM stable package from apt-get. Could you recommend me using a compiled newest or newer version instead of using the old one KVM package from Debian ...
4
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1answer
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How to connect a KVM guest to the internet with wireless

Because my wireless network adapter does not support bridging, it is really difficult to get the guest VM to connect to the open internet and have an IP address in the same network as the host. I am ...
4
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3answers
737 views

Error when try to install KVM on CentOS

I am trying to install KVM from Installation doc. When I run the command modprobe kvm-intel I get the error FATAL: Error inserting kvm_intel ...
4
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2answers
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How to use a 64-bit CPU in KVM?

According to tests the Mac Mini 3,1 CPU is 64-bit (grep -q "^flags.*\blm\b" /proc/cpuinfo) and supports Intel virtualization extensions (grep -q "^flags.*\bvmx\b" /proc/cpuinfo). However, after ...
4
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1answer
215 views

Poorly performing java application vs poorly performing server

This is a very generic question, but it has been coming up more and more often for me. I would like to try and determine an appropriate course of action for this generic case, as I think it could ...
4
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2answers
477 views

Copying large file causes excessive swap

On a mid-class CentOS 6.4/64 server with 32 GB RAM, 3 TB free disk space, operating as KVM hypervisor, I start copying a 200 GB file to a destination in the same local filesystem. In fact, this file ...
4
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1answer
485 views

Emulate unplugging a network cable with qemu-kvm

[Background: I'd like to actually test How to take down a static network interface when not connected? ] I'm setting up a QEMU-KVM virtual machine using libvirt (via virt-manager). I put two NICs on ...
4
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2answers
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bridged networking with kvm

I'm trying to get a guest virtual machine connected to my network using bridging. I've come across a couple of resources online, but they seem to be out of date, deal with xen or Ubuntu or don't seem ...
4
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1answer
180 views

setup kvm on a wireless interface on a laptop machine

I am trying to setup KVM in ubuntu 14.04 host machine. I use a wireless interface to access the internet in my machine. I have setup the wireless interface in my /etc/networks/interfaces as below. ...
4
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2answers
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CPU usage of KVM

I have a linux host with 4 KVM linux guests. All the guest are pretty much idle, having a load of <0.1 inside the guest. Now, if I do a top on the host, each KVM process is using something about ...
4
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1answer
539 views

SELinux interfering with host/guest file sharing using KVM

I'm running Fedora 17 with KVM and the virtual machine runs okay. I tried to follow this to get access to a file on the host system but SELinux prevents the VM from accessing any files other than ...
4
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3answers
124 views

What is contained in these addresses?

I am working on MUlti-processor record-replay feature of a virtual machine. I have a log of non-deterministic memory access done in the virtual machine by virtual CPUs. A very high proportion of these ...
4
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1answer
487 views

X and xdotool in LXC instead of KVM

So far I am using various xautomation/xdotool scripts in a KVM virtual machine (linux guest) in order to let them do their work and let me work uninterruptedly. I am using a VirtIO disk, but still the ...
4
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1answer
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qemu - two clients (tap0 & tap1) via br0 can't ping eachother but server pings ok

I've got: A host system running Ubuntu with KVM (functional) Two clients, one Ubuntu and one Windows 7, nothing fancy. I've also setup (see below) a bridge via br0 for the clients: br0: ...
4
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1answer
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kvm doesn't load Windows 8

I'm launching kvm with the following parameter: kvm -m 2g -smp ncores=2 -hda disk.img -cdrom win8.iso My CPU has VT support and enabled, EDIT I seems to have limited emulate type: pc ...
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2answers
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How to know if a process is attached to a tap interface?

I sometimes come upon machine with tap interfaces (eg, when KVM is running). How can i know which process is attached to the tap interface ?
4
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1answer
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One host, two virtual machines that cannot ping each other. How to solve

We have Virtual Machines operating within the KVM environment. We setup one as a dev server running Apache etc., and the other as a Windows development environment. The two environments are setup ...
4
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2answers
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Clipboard doesn't work in KVM.

I have a RHEL 6 Desktop with a windows KVM. How could I get the clipboard working, just as there is a solution in VirtualBox to share the clipboard between host and guest?
4
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0answers
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Socksifying a qemu-kvm using tsocks

I'm trying to socksify a qemu-kvm using tsocks, but I have no success. I don't know if qemu access directly the hardware, skipping the OS or something like that, but I wasn't able to do this feat. ...
3
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2answers
2k views

How to Add Extra Disks on KVM based VM

I installed Redhat 6.4 on KVM Server. Right Now there is only One Disk /dev/vda. Now I need to add extra Disk like /dev/vdb I tried adding New Volume but it is not showing when I do fdisk -l How to ...
3
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1answer
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How to install KVM on CentOS 6

I can't install kvm on CentOS. I got these errors: [root@localhost etc]# yum groupinstall kvm -y Loaded plugins: fastestmirror, presto Loading mirror speeds from cached hostfile * base: ...
3
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2answers
103 views

How long could I work with stable release after it is no more supported?

I'm still working on Debian squeeze which will be supported for only about 1 more year (it is server with KVM). How long is it possible to work on an old version of Debian (after Debian gets old) when ...
3
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2answers
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Wireless bridged networking in KVM. Why is it so complicated?

I've been using VirtualBox (and sometimes VMWare) for years and I've never had any problem with the virtual network adapters, no matter if the physical ones were wired or not. I also played some time ...
3
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2answers
664 views

Which user group can use the 'tap' net device?

I use the 'tap' net device with KVM to get my vm connect to the Internet. But I have to be root, or use 'sudo', which is inconvenient. I think I can put my user account into some group so I can access ...
3
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1answer
679 views

Can virtfs/9p be used as root file system?

Is it possible to use a folder shared from the host to the guest via virtfs/9p as the root file system inside the guest? Loosely related to my previous question: Can virtfs/9p be used to share the ...
3
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3answers
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Installing centos and freebsd with serial console

I am trying to install Centos 5.7 and FreeBSD 8.2 on KVM with serial console access. This is what I used: sudo virt-install -n freebsd -r 1024 --vcpus=2 --os-type unix --accelerate -v --disk ...
3
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1answer
139 views

Run AVD and VirtualBox at the same time

I'm developing for Android so I have the Android SDK installed and in it the program that runs virtual machine. Also, from the same reason, I'm running a oracle virtual box to host myself a redmine ...
3
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1answer
813 views

How to create KVM guest with SPICE graphics but TLS disabled using virt-install?

I am using virt-install (see below) to create a guest. All seems fine up to the point where it complains about auto-allocation of the SPICE TLS port. Here's what I am running and the full output: # ...
3
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1answer
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Install grub on LV container for VM

I'm having difficult time installing grub in LVM LV container for a VM. This is the partition table: # parted /dev/mgtvg/linux2os print Model: Linux device-mapper (linear) (dm) Disk /dev/dm-7: 129GB ...