QEMU stands for "Quick EMUlator" and is a processor emulator that relies on dynamic binary translation to achieve a reasonable speed while being easy to port to new host CPU architectures.

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2answers
127 views

Installing VirtIO SCSI on Windows Guest fails

I'm running Windows 10 as guest via KVM / qemu. Unfortunately, Windows doesn't recognize the fedora virtio drivers I want to install for better HDD perfomance. The driver itself does show up, but ...
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0answers
9 views

Gentoo virt-manager IO throttling

I have a problem with virt-manager (or qemu/libvirt) installed on gentoo. Here is My virt-manager installed on Debian Jessie virt-manager-debian There I have IO throttling but not on my Gentoo.. ...
1
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1answer
2k views

How to fix a frozen qemu VM?

I have a qemu hypervisor on RHEL 6.4 that hosts VMs that will quite often lose their connection to the network. When the VM has lost its connection I can view and interact with the it using ...
0
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1answer
2k views

qemu-img snapshot on live VM

I have created multiple KVM VMs using QCOW2 images. Each VM has its own qcow2 file and is not based on any backing file. My question is specifically related to snapshots of QCow2 images on these ...
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0answers
19 views

How to boot livecd linux distro under kvm virtualization with virt-install or virsh?

I am trying spin up a small livecd linux distro with virt-install under KVM and got access to it via virsh console. And I am kinda loss with --location, --livecd and --cdrom parameters. How should I ...
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1answer
13 views

QCOW2 virtual size lowering

I'm trying to get the virtual size of a qcow2 container down so that it can fit in a openstack flavor with 10GB disk. root@node-10:~# qemu-img info zztop.qcow image: zztop.qcow file format: qcow2 ...
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3answers
2k views

attaching usb dongle to KVM VM

I'm struggling to connect a usb device, that gets detected correctly by the host, to a kvm vm. I have a freshly installed Ubuntu Server 14.10 as KVM/QEMU host. I set up an Ubuntu vm using this ...
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1answer
2k views

Debian Jessie Qemu KVM GPU Passthrough to Windows Virtual Machine guest Virt-Manager error Bus PCI not found

I'm having problems with Virt-Manager not wanting to boot a VM and giving error: Error starting domain: internal error: process exited while connecting to monitor: char device redirected to ...
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1answer
24 views

KVM/QEMU: “Storage parameter error: directory is not managed on the remote host” when importing an existing image from a mounted drive

A server I manage remotely has a KVM/QEMU image stored on a non-os, mounted drive /mnt/drive. When I use virt-manager to import the disk image, I get the following error: Storage parameter error. ...
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0answers
29 views

KVM/QEMU Connecting guests only to other guests

Heyho guys, I have one host machine with multiple VMs on it. Their gateway is the host machine (which is doing some NAT etc.). There's one bridge at the host machine and a default virtual network ...
0
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2answers
1k views

Guest networking not working on Debian Jessie Host server KVM with br0 bridged network

GUESTS networking not working at all. In other words guest can not ping host or lan gateway. I have br0 bridge already created, also brctl show that vnet0 was properly added by KVM to br0 on guest ...
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0answers
12 views

Errors after unmounting qcow2 image with LVM

I successfully mounted a qcow2 image on my machine (the guest image uses LVM) using: qemu-nbd -c /dev/nbd0 /path/to/qcow2/file mount -o rw /dev/nbd0p1 /mnt/<mountpoint> vgchange -ay VolGroup ...
0
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1answer
40 views

How to forward a port from guest to host in qemu (kvm)

Is it possible, and how, to forward a port from guest to host in qemu/kvm? Note do I mean (out of) from guest to host, and not from host into guest (that's widely documented). I think I'm looking ...
0
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1answer
25 views

QEMU, Virsh and SMBIOS tables edit

I am currently running qemu-kvm on an Ubuntu server box and I use libvirt with Virsh to create, manage, start and stop VMs. I edited VM's XML configuration through virsh edit command to change CPU ...
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0answers
16 views

How to configure libvirt to allow console access

I was able to run a Raspbian image with libvirt using this XML configuration file. I can SSH into the VM just fine, but when viewing the "console" with the virt-manager GUI, I never get a login ...
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0answers
11 views

How to run a Raspiban in QEMU [migrated]

How do you run a standard Raspbian image in QEMU? I'm following the instructions in this wiki, but the first step is failing. I downloaded the kernal kernel-qemu-4.1.13-jessie and the Raspbian ...
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0answers
16 views

How to install Ubuntu ARM image with virt-install

How do you use virt-install to create an ARM virtual machine for running an Ubuntu ARM Raspberry Pi image? The docs are unclear to me, but from reading the manpage and looking at several examples, I ...
0
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1answer
57 views

Difference between qemu-kvm, qemu-system-x86_64, qemu-x86_64

For new features, I recently updated qemu-kvm 1.5.3 to qemu 2.5.0, but I saw several qemu binaries, /usr/local/bin/qemu-x86_64 and /usr/local/bin/qemu-system-x86_64. It seems qemu-system-x86_64 is the ...
0
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0answers
11 views

How to make live snapshot in qemu?

I have two live qemu virtual-machines with KVM support(-enable-kvm) in daemonized mode(-daemonize). I don't use libvirt. One of those virtual-machines use virtual HDD in qcow2 file-format and another ...
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0answers
640 views

Using NAT in qemu

I have used Qemu to install a windows xp guest. The command I run is qemu -m 2048 -gda winxp64.img \ -boot d -usbdevice tablet \ -enable-kvm -vnc :10 \ -netdev user,id=network0 -device ...
3
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2answers
572 views

Qemu+libvirt+kvm significant performance lag in VM's

I am troubleshooting poor performance on our new VM host machine which is a Dell PowerEdge R415 with hardware RAID. We've got about 20 VM's running like this: qemu-system-x86_64 \ -enable-kvm \ ...
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1answer
28 views

qemu-img: Could not open '/dev/stdin': Could not refresh total sector count: Operation not permitted

I want to transfer block device contents over the network directly into a qcow2 image. I started with a small simulation: [root@okvmh1 default]# dd if=/dev/zero bs=1M count=100 | qemu-img convert -p ...
0
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2answers
37 views

virsh qemu kvm editing xml has no effect

When I try to add a network section to a kvm/qemu xml, the xml wont update with the information. When I edit the uuid, or make a mistake, i get an error. if i change the memory amount, it reverts to ...
3
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1answer
34 views

vlan qemu: guest listening from other guests

I'm trying to simulate a little network of 3 machines using QEMU where a machine (deb1) is directly connected with the host and the other 2 machines (deb2, deb3): Host ...
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0answers
8 views

libvirt-Can I use 'virsh save' this command only get 'vm physical memory'?

I use 'virsh save ' to create an image,but I only want to get 'vm physical memory'.I don't know how to do it now.If you know the answer please tell me.Thanks!
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1answer
24 views

Modifying qemu without screwing up my current install

I currently have kvm installed on my Debian laptop: kvm --version QEMU emulator version 2.1.2 (Debian 1:2.1+dfsg-12+deb8u5a), I want to modify it to supported nested virtualization (ESXi VMs). ...
0
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0answers
34 views

Proxmox-Server reboots sporadically

I just mentioned that my proxmox-system is rebooting from time to time when performing backup-tasks (bacula, not the proxmox-backup-system). The logs are showing the following: Mar 8 02:30:01 ...
0
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1answer
35 views

Serial communication between QEMU host and guest

I'm trying to set up a pair of serial ports between my QEMU host (Debian Jessie x86_64) and guest (also Debian Jessie, but on ARM). Everything except the serial port part works. I'm really new to ...
1
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1answer
55 views

What are the steps to export a VM from KVM to ESXi?

I want to be able to export a KVM based VM to an ESXi 5.1/5.5 host. My current methods ends up with the VM not being able to boot on the ESXi host. (I have tried importing the same .ova on VirtualBox ...
2
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1answer
148 views

KVM / QEMU: connect to VM without GUI [closed]

Short Version (Solution is below): I have a Windows PC. I have a Debian server (without desktop environment). I have a Ubuntu VM running on Debian server via KVM/QEMU. Question: How can I connect to ...
0
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1answer
225 views

Live Backup using Proxmox's snapshot-drive command

I have a KVM server(not on a proxmox node), my VPS is based on qcow2 format and I would like to do a live backup of the vms. I have understood there are two types of backup, Internal and External, I ...
0
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0answers
49 views

Libvirt & USB Hub Passthrough

I have a virtual machine which I wish to have a USB Hub and all of its devices allocated to a virtual machine. The Hub in question is a USB hub which itself is plugged into one of the ports on the ...
5
votes
4answers
3k views

How to efficiently share host's folder with KVM guests?

I am configuring the service which stores plenty of files uploaded by nginx in /srv/storage dir on host system. These files are processed by worker KVM guests which may create new files or assign ...
1
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4answers
312 views

How to “really” reduce the size of KVM VMs images?

I've spent many hours searching the web about how to shrink KVM virtual disk images, especially for Windows guests, with no luck. All I've found is to zeroize the VM free space, defrag the virtual ...
0
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0answers
32 views

KVM is there a way to map physical memory to host. Like Xen mapping to Dom0

Been looking for an answer to this for a while. I am switching over from Xen virtualisation to KVM, and have been reading about KVM's ability to overcommit memory. I was wondering if anyone can help ...
0
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1answer
38 views

How to create virtual networks by using libvirt?

I have installed qemu/kvm and have tried to create some virtual machines and network them together. What I would like to achieve is 2-3 virtual machines in their own private network (e.g. ...
6
votes
2answers
30k views

'Unrecognised disc label' - when using parted with qemu images

I have a Linux from scratch LiveCD running on qemu vm. I'm using this command to create a hda disc for qemu: qemu-img.exe create -f qcow2 base-linux.img 5G Then I run my vm: qemu.exe -m 1024 ...
0
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1answer
117 views

virsh adding x2apic, cache specific options to kvm config

Anybody know the syntax how to add +x2apic to the virtual machines xml files when I edit them with "virsh edit vm"? From the command line it would be starting with this flag: qemu -cpu ...
1
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0answers
33 views

How does Qemu handle memory?

I'm having a real hard time understanding something and I was wondering if anybody has any experience with this and is able to help. I have two KVM VMHosts, one running qemu 2.4.1 and the other ...
0
votes
1answer
106 views

Ubuntu + bridge +qemu + tap + virtio dropping packets

I've got what I think is the standard qemu bridge/ubuntu tap interfaces set up running variety of VMs on my Ubuntu host. All the VMs I'm having trouble with are Windows images. I have researched this ...
0
votes
1answer
77 views

Correct virtio setup on Ubuntu 14.04 64-bit host

At the present moment, my guest is running inside qemu and host is kvm intel, running Ubuntu 14.04, kernel is 4.3.0 stable. From within the guest, when I run "hdparm -i /dev/sdb" on the guest, I ...
6
votes
2answers
14k views

Which is better image format, raw or qcow2, to use as a baseimage for other VMs?

I am using a baseimage and based on that creating many VMs. And now I want to know which is better, qcow2 or raw to use for a baseimage. Moreover, can you please tell me if there is any advantage of ...
1
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1answer
20 views

Is a QEMU installation on a raw disk backward compatible?

I create a qemu image like this: qemu-img create -f raw my_disk.raw 2G and (manually) install debian into it: qemu-system-i386 my_disk.raw -enable-kvm -m 1024 -cdrom my_debian_cd.iso Say I do ...
0
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0answers
135 views

FreeBSD 10 guest on qemu/kvm CentOS 7 host

I'm trying to install FreeBSD 10 on CentOS host without using graphics (using only serial console). I've tried: # virt-install -n freebsd-a -r 512 --vcpus=1 --os-variant=freebsd10.0 --graphics none ...
3
votes
1answer
46 views

KVM port binding

I followed this tutorial to install a KVM virtual machine on my ubuntu server. Now i need to bind a port from the guest to the host. I tried several tutorial to bind the port, but nothing worked. My ...
2
votes
2answers
340 views

KVM top shows high CPU load on host for windows7 guest though windows is on idle

we have an virtualization environment with actually 4 VMs (2 x linux, 1 x w2k3, 1 x win7). In the host system (Debian Jessie) top always shows a CPU load of 30-70% (or more) for the qemu process of ...
13
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3answers
16k views

free up not used space on a qcow2-image-file on kvm/qemu

we are using kvm/qemu with qcow2-images for our virtual machines. qcow2 has this nice feature where the image file only allocates the actually needed space by the virtual-machine. but how do i shrink ...
1
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2answers
147 views

KVM: Need multiple Virtual Machines to share a VLAN'ed interface

I'm not sure how to configure my Linux server which has a single VLAN'ed interface to support a number of Virtual machines which I want to bridge to my network (so that all their services appear to ...
3
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1answer
69 views

kvm snapshot-create-as failed

I have Ubuntu server with qemu/kvm. I'm try to create snapshot (for further backup) using libvirt and get this error: # virsh snapshot-create-as --domain 56 --name copy_snap --no-metadata --disk-only ...
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0answers
142 views

Proxmox/KVM: Can not clone VM

I would like to create a clone of a KVM machine - yesterday I was able to create a clone of the same machine within some minutes. Now it takes hours and is still stuck an "0%": create full clone of ...