Questions tagged [kvm]
KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V).
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Libvirt virt-install Ubuntu Server 22.04 Stuck on Console [closed]
I'm trying to automate the virtual machine creation process, but I'm encountering an issue with the following command. The command runs without errors, but the virtual machine seems to require user ...
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How can I add additional tagged vlans when using virt-install to create a guest?
I'm unable to figure out the XPath syntax to add a second tagged vlan when using virt-install to provision a guest:
srv01:~$ sudo virt-install\
--name=ds-controller01.iwc.ig24\
--disk source.dev=/...
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Meaning of the npages member in the struct kvm_memory_slot
Recently, I've been working on live migration of virtual machines. I'm curious about the calculations of member npages in the kvm_memory_slot struct of kvm. The npages are initialized in the ...
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Why do i get dev/kvm : No such device after installing kvm?
I am getting the error while running an emulator on my WSL Ubuntu 22.04.3 LTS on Windows
The error came when i already installed kvm in my ubuntu server and trying to create an avd device.
lsmod | ...
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How can I update the baking file of qcow2 snapshot after the files have already been moved?
I am running Kubuntu (Ubuntu + KDE) with libvirt/qemu/kvm to run VMs.
I have a Windows 11 VM. When I created it, it created a .qcow2 and now I have a snapshot file.
The original file paths were:
/var/...
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Vagrant-libvirt: could not get preferred machine for /usr/bin/qemu-system-aarch64 type=kvm
I'm having issues with running an arm64 machine using vagrant with the vagrant-libvirt plugin.
Here's the Vagrantfile:
Vagrant.configure("2") do |config|
# Disable synced folders
...
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Qemu version 2.9.0 and later doesn't support legacy networking mode on gns3
When i start my nodes in GNS3 i get the following error message : Q emu version 2.9.0 and later doesn't support legacy networking mode . How can i fix this. Do i have to do downgrade to a 2.8.0 ...
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Properly Configuring Host Port Fowarding to QEMU/KVM Guest
Can someone please show me what i am still doing wrong with the port fowarding on my KVM host?
If i try to go to the port 22596 from localhost it still doesn't forward to 8096 as specified. The ...
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What happens when meet an exception?
I'm studying the part of kvm in linux and it seems that when the we meet an exception during kvm_run, the program will stuck in endless loop to deal with the execption.
For example, when I let kvm run ...
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Can the hypervisor and VMs share memory?
I was wondering if modifying the KVM would allow the hypervisor and VM to share memory.
I've been studying SEV, AMD's memory encryption technology, and this question came up.
Is it possible for the ...
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ActiveMQ Classic on Ubuntu 22.04 on VM starts but immediately exits
This installation was done on my KVM/Ubuntu by apt install, but I had the same problem after installing via download and unzipping everything in /opt and setting up the service file, etc. When I use ...
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Azkaban Executor Java Process CPU usage very high, The "top" command shows high sys usage
I have an Azkaban executor server process, which is a Java service.
I noticed that when running a random sleep script, the CPU usage becomes very high, consistently exceeding 2000%, and the "top&...
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virStorageFileBackendFileRead Failed to open file '/dev/...': Permission denied
I'm trying to bring up a VM through virsh define, virsh start. The command doesn't show any errors and virsh list shows the VM is running. However, I can't access to the console, so I checked the ...
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Hyper Threading: nosmt in grub configuration
Currently, I have running Debian 12 instance on dedicate CPU cloud environment. It has 2 cores, 4 threads.
It is not impossible to turn off hyper threading via BIOS settings.
I found possibility to ...
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Passing Intel-PT to guest using QEMU/KVM doesn't work
I am trying to use Intel-PT feature inside a guest ubuntu using QEMU/KVM, but although I have this feature in the host, KVM is not passing this feature to the guest.
Also when I try to load kvm_intel ...
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Get NT_STATUS_ACCESS_DENIED from smbClient / Samba despite Linux root
I always get the access denied error when I try to connect smbClient to my samba shared directory.
So I try to use:
sudo smbclient "\\leon-pop-os\img_mount" -U root
I get as Expected:
...
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1
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242
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How to start a KVM-QEMU VM once we connect to the VNC port by systemd sockets?
I am trying to keep my virtual machines in a non started state until they are needed. And then keep them on until the users or I turn them off.
I'm trying to auto trigger the connection to the VNC ...
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QEMU execution traces for a simple program (guest mode)
I am starting my QEMU VM with the following command to get the execution traces for a simple hello world program in C.
qemu-system-riscv64 -singlestep -d nochain,cpu -D $trace ${binary}.
For guidance, ...
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Getting dynamic execution traces for running a program in QEMU
I am running Fedora in QEMU for RISC-V ISA (64 bit). I have queries with regards to getting the dynamic execution traces as shown here(slide 3.3). This is my boot script for initialing QEMU:
qemu-...
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Enable KVM on GitHub Actions for private repository
I need to run an Android emulator in my GitHub Actions workflow for integration testing. As I read here this can be done with this step:
- name: Enable KVM
run: |
echo 'KERNEL=="kvm", ...
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What is /dev/kvm device in kvm virtualization?
What is /dev/kvm device in kvm ? I searched on google, but could not find any article on it. Can someone who is familiar with it, point me to any helpful resources ?
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Unable to disable rx-checksumming on virtual machine NIC
I am trying to build a VPN server on a virtual machine and the throughput is significantly low due to the fact that checksum offload is enabled on the NIC. I have run ethtool -K enp1s0 rx off tx off ...
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Linux vhost kvm exit upon guest sending a packet
According deep-dive-virtio-networking-and-vhost-net a benefit of Vhost protocol (virtio-net guest driver & vhost-net host driver) is that when the Guest send a packet there is no need for the vCPU ...
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How to create a persistent network using libvirt-java
I would like to create a network with both persistent and autostart flags set using libvirt-java:
Connect connect = new Connect("qemu:///system", false);
Network network = connect....
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80
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what happens when an external interrupt is received by the host in a virtual setting
I'm trying to understand what happens in a virtualization setting when the host receives an external interrupt. For example if CPU-1 is being utilized by vCPU-0 of a VM and there is an external ...
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how does irqfd trigger interrupt in the guest
I'm trying to understand irqfd's and how KVM can interrupt the guest and have it execute its interrupt handler. This document mentions binding a file descriptor to an interrupt but the entire flow of ...
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How to monitor vcpu registers with kvm_sync_regs in kvm_run?
I would like to loop (;;) over the kvm_run structure during a guest execution, in order to monitor the vcpu registers. While reading the documentation, I saw that using the get_regs/set_regs were ...
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Start pure X11 with fullscreen remote-viewer to started KVM instance
Intention is to start LightDM session with only VM and connecting app working, so no other apps will interfere with its usage.
I've created .xsession which starts KVM domain and remote-viewer in ...
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Using sudo with `virt-install` returns an error Permission denied on qcow2 disk
I created a qcow2 disk using qemu-img, i.e.:
qemu-img create -f qcow2 -F qcow2 -b /home/user/Downloads/bionic-server-cloudimg-amd64.img ./ex-os.img 10G
Next I tried to create a VM using virt-install ...
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How to turn off MSI in KVM's PCI Passthrough?
In ESXi VM, you can disable MSI in PCI Passthrough with
pciPassthru.msiEnabled = FALSE
How to do it in virt-manager XML for a VM with QEMU/KVM?
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How to get the number of instructions executed inside a virtual machine from the host?
I have attempted to use the perf kvm stat -p vmpid command to get the number of instructions executed.
However, I have observed that the command still reports a significant number of instructions even ...
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How to check if free page reporting is supported by qemu?
I know that we can login into the QMP shell and run "device_add driver=virtio-balloon-pci,help" and see if there is "free-page-reporting" option or not but Is there any other way ...
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kvm guest host get ip by dhcp failed when cloudflare-warp on open
My English level is not high, please forgive!Thank you so much!
I searched a lot of information but couldn't find the answer.
question:
after cloudflare-warp connect，kvm guest host get ip by dhcp ...
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390
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How to change vendor and product name on QEMU?
I am using Libvirt along with QEMU/KVM virtual machine. I wish to change the product name and vendor of my SATA drive but it tells me it can on be used for SCSI drives as seen here:
Error changing VM ...
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Why mannually setting the vlan id to the VF attached to a VM will not work?
The working config is like this:
<interface type='hostdev' managed='yes'>
<mac address='52:54:00:6a:9d:7f'/>
<driver name='vfio'/>
<source>
<address type='pci' ...
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Libvirt/KVM/Qemu Guest does not connect to internet
I am creating VMs on the go with libvirt. My host is an Ubuntu 22.04 LTS wired to an ethernet cable. I have already tried NAT Networking and it works perfectly but I am trying to move to bridge ...
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KVM VM Install successfully by virt-install but cant connect
After reading wiki libvirt I started virt-install to install Ubuntu(14.04,16.04,18.04,20.04) by a serial console installation,I installed ubuntu14.04-server and connected successfully,but something ...
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What happens i run 2 goroutines to modify a VM and destory the same VM using libvirt-go package on the same instance?
As we know, libvirt is thread-safe.
But running two goroutines concurrently acting on the same resource, such as modifying and deleting a VM leaves it in an ambiguous state. How does libvirt decide ...
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Uploading a switch appliance on GNS3
I recently installed GNS3 on Ubuntu, using KVM-qemu as the virtual machine. I installed the GNS3 on a remote server hoping to work on topologies with my friends. The installation was successful but I ...
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KVM Virtio-balloon: how to activate free page reporting feature on the device side?
I'm trying to get free page reporting running on my KVM guest (Ubuntu 22.04 server with custom kernel from upstream Linux 6.5). My host is Ubuntu 20.04 with 6.5 Linux. Free page reporting is listed as ...
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How can I ensure fitting user right for .qcow2 file in my terraform implementation
I have debian based kvm/qemu installation and want to deploy a virtual machine via terraform.
provider "libvirt" {
uri = "qemu:///system" # Verbindung zur lokalen QEMU-Instanz
}
...
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523
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Why is pip install libvirt-python failing and saying I need libvirt installed, even though libvirt is installed?
I am running RHEL 9.2 with Python v3.9.16, and I am trying to install the libvirt-python Python package. I have tried installing using pip and pipenv, and I get the same error every time.
I have the ...
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how fix problem [org.ovirt.vdsm.jsonrpc.client.reactors.ReactorClient] (SSL Stomp Reactor) [] Connecting to ovirt
please tell me how I can solve this problem?
after an unexpected server reboot with Ovirt, the host and the storage domains were disconnected, the cluster does not rise.
I see such errors in the logs /...
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How can I start multiple virtual machines using QEMU and how to specify each VM to run on a specific core?
I am trying to run multiple virtual machines on the same host using QEMU with KVM acceleration. I am also trying to get each virtual machine to run on a specific CPU cure. For example, I want to ...
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Cloudstack System VM Networking not working
I've set up a CloudStack testing environment using two VMs: VM 1 has Ubuntu, NFS and KVM installed. VM 2 has Cloudstack installed.
The issue is, that the generated system VMs don't seem to be able to ...
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SDDM on Wayland crashes in test mode
I am trying SDDM on Wayland in a VM but I am not able to get it to work.
My system maybe is a little unusual:
The host is a Mac Mini (old one - Late 2012) on which I run Ubuntu 23.04
On this I run ...
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Clipboard sharing is not working, but the screen resolution resizing is, after I setup "spice-guest-tools" on a win 11 VM
I'm running Kubuntu on the host.
I've installed a VM using QEMU/KVM and virt-manager. The VM OS is Windows 11 Pro. I've setup "spice-guest-tools" on the VM, and setup "spice-vdagent&...
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Cloud-init 18.5 module execution fails before creating the SSH keys
I am provisioning a virtual machine which executes the cloud init script on its first boot. I have a floating IP assigned to the VM and I can ping it, but can't ssh into it. I suspect that the cloud-...
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Creating Windows VM in KVM/QEMU using GNOME Boxes from a Backed-Up OS
Hello Stack Overflow community,
I'm looking for guidance on how to create a Windows virtual machine using KVM, QEMU, and GNOME Boxes on a Linux system. I have recently migrated my Windows and ...
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