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? ...
11
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2answers
1k views

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 ...
10
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2answers
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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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2answers
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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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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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4answers
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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 ...
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 ...
6
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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: ...
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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 ...
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
714 views

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, ...
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
656 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
votes
1answer
53 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 ...
5
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3answers
2k views

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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1answer
446 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 ...
5
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0answers
66 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: ...
4
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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 ...
4
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3answers
585 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
3k views

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
615 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 ...
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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
80 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
341 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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2answers
4k views

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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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
416 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
1k views

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 ...
4
votes
1answer
701 views

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?
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0answers
175 views

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
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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
6k views

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
102 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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1answer
289 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 ...
3
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2answers
5k views

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"?
3
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1answer
529 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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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 ...
3
votes
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
votes
1answer
115 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 ...
3
votes
1answer
953 views

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 ...
3
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2answers
2k views

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 ?
3
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1answer
528 views

What happens if you add a vlan-device to an interface that already is a vlan device?

When configuring an application that creates vlans by using vconfig add, I discovered that it was adding a vlan device to something that was already a vlan device. Effectively, what happened was: # ...
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2answers
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Mouting a kvm qemu disk image with multiple partitions

I am trying to mount a KVM-qemu disk image with this command: sudo mount -o loop,offset=32256 centos6.img /mnt/centos6. But it shows this error: you must specify filesystem type. As I have more ...
3
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2answers
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How to install kvm in Debian (Lenny) over powerpc

I am emulating powerpc using qemu-system-ppc on top of x86, and running debian-lenny-ppc with it. I want to install kvm inside that debian. I have learned that the kvm and qemu-kvm packages are not ...
3
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1answer
36 views

Sharing partitions in qemu

Apart from networking and partition sharing I've made qemu work pretty much like I want it to. I've got a bit of a special setup, I need to pass through /dev/sda, /dev/sda1 and /dev/sda2. (Is it ...
3
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1answer
314 views

Proxmox Master Node crashes

I've inadvertently discovered a Proxmox bug. I run a personal cluster of 4 nodes (a technology lab for giggles and gags). Each node has a Dell Perc 5i and 4 HDDs in RAID 10. The standard Proxmox ...
3
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0answers
396 views

VGA passthrough - Code 43 with KVM and libvirt on all AMD hardware

I've set up a system with an R9-270 and an ATI Rage (PCI graphics card, doesn't use radeon driver) on an FX-8320 and an ASRock 970 Extreme3 R2.0 motherboard with the intention of running Debian Wheezy ...
3
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2answers
152 views

How to report back system installation progress

I'd like to do some reporting from the system setup progress for virtualised (libvirt/kvm) Ubuntu servers. I expected some kind of such system to already exist out there, but couldn't find anything. ...