QEMU (short for "Quick EMUlator") is an open source machine emulator and virtualizer.

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How crazy is “sudo qemu -hda /dev/sda”(mounting host's sda as client's hda)?

I was playing with qemu on Linux when I discovered that I could just run sudo qemu -hda /dev/sda And it would boot up my system again! I closed qemu immediately after Grub was loaded successfully ...
9
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2answers
335 views

Full hardware emulation

I want to emulate some old desktop PC in order to run my application there (the emulated machine) as a stress test. Is this possible? I looked around and some people mentioned Qemu, which is Open ...
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2answers
18k views

Is it possible to resize a QEMU disk image?

Like the title says: Is it possible to resize a QEMU disk image in Linux? And if so, what happens to the partitions within it? Are they automatically resized as well (doubtful) or is there just a new ...
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2answers
10k views

How do I convert an .img file to vhd?

I have an image file (linux based image) and want to convert it to VHD so that it can be used to create hyper-V VMs. I used "qemu-img convert" to convert raw to vpc format, but vpc doesnt work for ...
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2answers
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Does QEMU's performance (still) lag VirtualBox's and is there a way to improve it without the hardware support+kvm kernel module?

I've noticed several articles that have claimed that QEMU is slower than VirtualBox (without hardware assistance) but several are years old, and the newest seemed to be from last year. Is it true ...
6
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1answer
2k views

How to mount KVM virtual machine image to VirtualBox?

I have received a .img file of a server which is a Virtual Machine running in a KVM environment. The Virtual Machine has Ubuntu installed. I would now like to take this .img file and "emulate" the ...
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5answers
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Windows 7 fails to install on KVM with qemu

I'm trying to install Windows 7 on a virtual machine on my 64 bit Ubuntu Karmic box. I get to the point of selecting my language settings and clicking 'install now', but a short while later I get a ...
5
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1answer
750 views

ARM Compiled QEMU - “standard VGA not available”

I followed this guide to compile QEMU so that I could run a Raspberry Pi Archlinux image in it - which I learned how to do in this guide. I'm trying to run x-server on the virtualized Archlinux ...
4
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1answer
1k views

Qemu & VNC - how to use absolute pointing device

I'm using QEMU with VNC for display running a Windows XP guest OS. When I connect with a VNC client, the mouse pointer position is pretty badly correlated to where my real mouse pointer is. Is there ...
4
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5answers
671 views

How does it hurt to use Linux (Ubuntu) as a guest OS for all my tasks?

I have a machine running Windows, where the disk has two partitions C (50 GB) and D (250GB). I do research in Information Retrieval and need to work with a large corpus (more than 50 GB) and in ...
4
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1answer
4k views

How to enable network with a raspberry pi emulated on qemu?

I'm trying to emulate a raspberry pi on my ubuntu 13.04. I installed qemu and it works well except for the network. I followed this procedure. On the virtual machine, the file /etc/network/interface ...
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3answers
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Is there any way to run 64bit Virtual Machine on 64bit processor without hardware virtualization (amd-v, vt-x)?

We have a 64bit virtual machine (CentOS) that we'd like to run on 64bit host-machine (may be running under any OS), but that host-machine doesn't support hardware virtualization, which, you know, ...
4
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1answer
3k views

How to boot a physical Windows partition with qemu?

I have gentoo and windows 7 installed alongside on my only hard drive. I want to start my windows install from within gentoo through qemu. Boot menu works fine but windows bluescreens on me soon after ...
3
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4answers
8k views

Qemu in an ssh session or the quest for the nographic option?

I ssh to a machine and I would like to start a qemu session inside this ssh session. I thought that the nographic option would do the trick. -nographic Normally, QEMU uses SDL to display the ...
3
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1answer
480 views

QEMU: How to find bottleneck in my virtual machine?

I am running an ubuntu virtual-machine on a 12.04 ubuntu server. Unfortunately the machine is extremly slow (just htop consumes 15%), even though having 8 cores etc. Do you know a way to find the ...
3
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1answer
2k views

How do I get AVX support in QEMU?

I want to play with the new AVX instructions. I saw that QEMU might have support, so I built it from Git (yesterday). I set the CPU to SandyBridge and I booted Tiny Core Linux. TCL has kernel 3.0 and ...
3
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1answer
3k views

How do I bridge a connection from Wi-Fi to TAP on Mac OS X? (for the emulator QEMU)

I'm trying to setup a bridge between my Wi-Fi connection and an emulator (QEMU). I need a virtual machine to be on the same LAN as the host, with its own IP address. QEMU requires using a TAP ...
3
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1answer
400 views

What VNC clients support qemu's audio extension?

I've read that QEMU implements an extension for providing audio over a VNC connection Unfortunately despite doing a lot of web searches and even installing some different VNC clients and ...
3
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3answers
3k views

Installing Windows 8.1 64 on Qemu Fails - no disk can be found due to Virtio driver issues

I'm unable to install Windows 8.1 x64 with the following steps on a qemu virtual machine: qemu-img create -f qcow2 Windows8.img 20G qemu-system-x86_64 -machine pc,accel=kvm:tcg -cpu host -m 2048 ...
3
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0answers
1k views

QEMU within VirtualBox and bridged connections all the way down

I'm trying to get an ARM QEMU system out on my LAN. I tried running QEMU directly from Windows (Windows 7 x64), with success except I could not get a TAP adapter to bridge to my wireless connection. ...
3
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0answers
5k views

qemu: Set or force higher screen resolution than 640x480

I set up a virtual machine using qemu-system-arm (ARM emulation) running Debian squeeze. Now I have the problem that in the "Monitors" preferences, I can only select 640x480 as resolution. Tried all ...
3
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2answers
1k views

qemu - fastest user-mode emulation platform?

I'm planning to run Linux under user-mode qemu but don't know which platform (eg x86, ppc etc) is the best to pick (performance wise). The host is Linux x86-64 running in OpenVZ (so can't modify ...
2
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1answer
4k views

QEmu to share a directory with the host

My problem is that networking devices in my device tree are not very stable so I thought the best way to share a folder between qemu and the host system is mount the same img without cache on both ...
2
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1answer
2k views

qemu kvm - can't start VMs after installing xen hypervisor

I had been using QEMU KVM for long time and have few VMs. Recently I installed XEN Hypervisor following this instructions but decided to apt-get remove xen-hypervisor-4.2-amd64 Problem is that now, ...
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2answers
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How do I use the “-cpu” option in Qemu?

Using QEMU 0.14.1 under Ubuntu 11.10 with kernel 3.0.0-17-generic, if I run qemu -cpu ? I get: $ qemu -cpu ? x86 [n270] x86 [athlon] x86 [pentium3] x86 [pentium2] x86 ...
2
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2answers
200 views

What emulator / VM software can I use to create a Win32-portable Linux Guest?

I want to create a portable VM setup so that I can boot a Linux install regardless of which Windows XP / Windows 7 host machine I am on. I was looking at Qemu but it doesn't appear to have a ...
2
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1answer
1k views

How To Change The Floppy Image Of Qemu?

I'm developing my own OS, but I'm having some problems with Qemu, because I need to change the floppy image from grub.img to os.img while the emulation is running, but how can I do this?
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2answers
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Can the ARM build of ubuntu 11.04 run in Qemu (on Ubuntu 11.04 amd64)?

Is it possible to run the ARM image of ubuntu-11.04-preinstalled-netbook-armel+omap4 in qemu? (Also used on the Pandaboard) I have extracted the vmlinuz-2.6.38-1208-omap4 doing the following: fdisk ...
2
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1answer
5k views

How to access internet from QEMU?

I am running qemu version 0.13 on windows XP. My Host OS is Windows XP and my guest OS is Debian 4(Etch). How do I connect to internet from Debian OS? My windows OS can connect to Internet. The ...
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0answers
187 views

qemu: How to use resolutions > 1024x768 in Windows 8(.1)?

In previous Windows versions, I was able to get higher resolutions in qemu/qemu-kvm by passing the -vga std or -vga vmware command line parameters. However, when I try the same for Windows 8 (and ...
2
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2answers
131 views

Qemu user mode networking doesn't work

I try to use network in guest system. I installed an OS in a virtual machine, but I did not get the network configured. When I try to ping, for instance google.com I get the IP address for the domain, ...
2
votes
1answer
352 views

How can I get qemu's Ctrl+Alt keys working in -curses mode?

So here's the situation; I currently have qemu installed on an OpenBSD 5.3 snapshot. This is a console setup so I have to either run with -curses or -nographic. The problem here is that I'm having ...
2
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1answer
469 views

Problems switching to QEMU control panel with -nographics

It seems that the terminal does not recognise CTRL+ALT+2 when typed, so I don't know how to quit the QEMU emulation, or switch to the QEMU control panel. I am running Mac OSX Lion, and I type $ ...
1
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2answers
343 views

Virtual machines: QEMU, virtualbox

When I use virtual machine on my i5 laptop, does it emulate every instruction or does it run normally? How much is speed decreased? Especially I am interested in QEMU and virtualbox, how do they work? ...
1
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1answer
1k views

linux 'top' not showing all processes

I am running linux top command to see processes running inside qemu VM. Sometimes, a process does not appear in them, but if I run, ps -eo psr,pcpu,comm | grep myprocessname then the process is ...
1
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1answer
3k views

How to convert a VirtualBox virtual machine to QEMUwto image?

How do I convert a VirtualBox virtual machine to a QEMUwto image?
1
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1answer
178 views

iPod Touch 5G won't recognize in qemu Windows 7 VM

I have an iPod Touch 5G, and a Windows 7 VM. I am trying to pass through the iPod Touch to the VM so Windows can recognize it, but I am getting the following error in the qemu monitor. (qemu) ...
1
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1answer
949 views

open a console on a virtual machine

I have a KVM Virtual machine running, I can see that using "ps aux | grep kvm". What I need to open a console into that VM. How do I do that?
1
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2answers
1k views

GDB breakpoint problems attaching to QEMU

I have the following problem: When I connect gdb to qemu for debugging, it won't break on breakpoints. I can set breakpoints, break with ctrl+c etc. Any clues how this can be fixed? I have: $ qemu ...
1
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1answer
1k views

How to build a portable windows virtual machine without admin permissions and with high performance?

I need to build a portable virtual machine that could be used on user restricted PCs that need admin permissions. I've heard about QEMU. But the problem is that it is very very slow when running. Is ...
1
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1answer
1k views

Unable to configure qemu on Ubuntu 14.04

I'm trying to configure QEMU on Ubuntu 14.04 (x64): $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 14.04.1 LTS Release: 14.04 Codename: trusty ...
1
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1answer
2k views

How do I create a wifi network bridge with qemu on OS X?

I grabbed a small FreeBSD live CD and QEMU, and I'm trying to bridge my Mac OS X 10.8 wifi connection so that the guest OS is available on my LAN. However, the guest OS never gets a DHCP lease. This ...
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1answer
80 views

Will QEMU emulate processors newer than the one in which it's running?

If I compile QEMU in Linux running on a 486 processor, will it be able to emulate the Pentium processor features on it (like MSR)? And, if it doesn't, is there any way to emulate the Pentium features ...
1
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1answer
449 views

Is it safe to uninstall qemu and libvirt?

Fedora installs both by default. I didn't found what are them exactly for, but yum autoremove selects them for autoremoval. Is it safe, for a normal user (I mostly use this machine for documents and ...
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1answer
2k views

How to use qcow2 disk image in Linux?

I have a large qcow2 formatted disk image, which I use as storage. Often I need to move data to and from this disk image. I mount the disk using the qemu-nbd tool as follows: modprobe nbd max_part=63 ...
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0answers
9 views

spicy-client assertion failure after computer crash

I usually use spice-client to connect to remote VMs without any problem. Today during usual work my pc freezed (I am strong confident that this is not due to spice) and forced me to brute shutdown. ...
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0answers
50 views

Using directory as initrd in QEMU

Is there a way to use a directory as initrd when booting QEMU? I know how to use the -kernel and -initrd flags for QEMU to boot a kernel and initrd without needing to first create a bootable device ...
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0answers
1k views

failed to access perfctr msr - When running Fedora on a VM

I'm trying to run a Virtual Machine with Fedora, and I choose to "Start fedora" from a list where I can start it or troubleshoot problems. The I get the following output: [ 0.00000] tsc: Fast TSC ...
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0answers
121 views

KVM Arch install - no network

I often use KVM to try out various Linux distros. All I have tried so far get an automatic network, Red Hat and Debian have all connected out of the box, no problem. Makes installations very easy. ...
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0answers
126 views

How to forward usb port to guest OS using qemu

I have lots of usb devices and I would like to connect them to guest os. Currently I'm forwarding one device at a time. $ qemu-system-x86_64 ... -usbdevice host:xxxx:yyyy I would like to give ...