Questions tagged [kvm-virtualization]
KVM (for Kernel-based Virtual Machine) is a full virtualization solution for Linux on x86 hardware containing virtualization extensions (Intel VT or AMD-V). It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. KVM also requires a modified QEMU although work is underway to get the required changes upstream.
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Networking KVM virtual machines to VLAN interface on host
I have a VLAN interface (enp98s0f0.4000) set up on my KVM host, which is a Hetzner dedicated server. The VLAN is set up to route through a Hetzner vSwitch, and I can ping out to Cloud instances ...
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KVM - Reduce Storage Size of QCOW2 File To Specific Size
I want to reduce the storage size of the VM's running on a Linux 8 physical machine from 2 TB to 400 GB. The actual size of VM's is around 100 GB. But the space we give it as allocated size is too big ...
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network does not work for VM after a while, only resolves after changing MAC
I have installed pfSense as a KVM guest in a Debian 11 host using libvirt.
The host has two interfaces. One is attached to the VM using macVLAN driver, and serves as pfSense's WAN interface. The other ...
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Machine type issue when migrating KVM VMs with live snapshots from Debian to Ubuntu
I'm trying to migrate around 40 KVM VMs (containing a few hundred live snapshots mostly used for automated testing on Windows) from a Ubuntu 22 server to a Debian 11 server. The machine type of most ...
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Cloud-init in kvm guests (Debian and Centos) not setting interface settings
Im trying to use cloud-init to setup kvm guests (currently Debian 11 and CentOS Stream 8), and I am looking for help in correcting the meta-data and user-data files.
Everything else seems to work, but ...
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How to make KVM guest configs persistent across reboots/shutdown
I create a KVM Guest VM (virsh define a.xml, virsh start a.xml). Guest uses pre-configured/pre-made QCOW2 disk image, which represents a virtual router (Arista vEOS). Host is Redhat 9.1. Guest is ...
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Connect (create ethernet link) between two VMs using their assigned SR-IOV Virtual Functions (VFs)
I have two KVM virtual machines created on RHEL9. I partitioned an SR-IOV-capable Physical NIC such that I was able to get Virtual NICs (Virtual Functions) from it. For each VM, I assigned it a VF.
...
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ebtables is causing packet loss
I am using AlmaLinux 8 on a dedicated server and hosting VPSes using KVM.
Applying ebtables rules on those VPSes is causing packet loss issue.
Bridge chain: v1001, entries: 1, policy: DROP
-p IPv4 -s ...
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QEMU SMP options
I'm trying to understand the QEMU smp option.
Currently I have set it to:
smp 4
As far as I understand that should create 4 vCPU (with 1 core and 1 thread I suppose).
Would it be better for ...
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How do I route ALL VM (qemu-kvm, libvirt) traffic through proxy running in Host?
Host: Ubuntu 20.04
Proxy Client and Server: V2ray
Proxy Client connecting to Server and is available in the host on 127.0.0.110808 for Socks and 127.0.0.1:10809 for http.
VMs: Multiple vms running ...
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Determine QEMU KVM overhead?
My guest OS shows about 5 percent CPU usage, but my host machine shows the QEMU process taking about 25 percent.
I'm trying to understand where this difference comes from, as I am using KVM ...
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QEMU load average vs cpu count
When I configure more CPU cores, the load average in my Guest OS as shown by top also increases linearly.
I'm trying to understand why this happens, because I expected either the opposite or at least ...
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Dynamic CPU allocation/scaling in QEMU KVM
How can I dynamically allocate/scale CPU resources to my QEMU VM according to the workload of the VM? Would this require a script? Is it even possible to change CPU allocation at runtime?
I have a ...
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Remove "lspci" devices from guest VM - possibilities and limitations
Prerequesites: some RedHat KVM hypevisor and Ubuntu server as guest.
So, I'm worryng about virtual pci devices, connected to my Linux VM (on VPS) by default. One of them is VGA device which lets ...
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KVM with public IP for a VM
I'm looking to build a VM using KVM/qemu in my dedicated server and assign to it one of the 2 Ip addresses I got assigned for my dedi. However, following this guide https://medium.com/techtalk-blog/...
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in Cuckoo sandbox how to setup simple gloabal routing using KVM as my guest machine?
im using kvm because the malware im analyzing has virtualbox detection.
ive gotten cuckoo working with virtualbox im having trouble with the kvm one.
I'm using ubuntu 18.04 as the main host.
ive tried ...
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vm machines cannot ping each other via bridge network [duplicate]
I created vhost1 and vhost2 by using virt-manager which run on a Ubuntu server 22.04
The Host and VMS connected via a bridge network. So here's the thing:
The ping working fine between Host and VMS, ...
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Use cloud server's network to serve local server's content
I am trying to build a web application for a local community. I'd like to host a postgres database, a SSR frontend server, a REST backend server. The internet and electricity are pretty cheap here and ...
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network-latency/ping degradation over time correlated with memory fragmentation
There is an Online Charging System (OCS) which handles Diameter Ro and Gy traffic. The OCS receives CCR Diameter messages and answers with CCA Diameter messages. And this response time - latency - ...
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virtual pfSense setup with virtual interfaces
I am running a linux Desktop, for virtualization I am using QEMU/KVM. In order to properly test my ansible Scripts I would like to create a virtual lab environment on my Desktop, that behaves like the ...
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Unable to install a VM in KVM: Error: Unable to destroy domain
I am runnging ubuntu server and I am unable to launch virtual machines, Initially it said permission denied but now it is also saying error: Failed to destroy domain 'esxi03' error: Requested ...
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How to use more then 2GB of ram when using running a nested BIOS VM using KVM
I have a Linux host running Debian 11 and on that host, I have a Ubuntu 22.04 VM. Inside that VM I want to run a Windows 10 VM using nested virtualization. The ubuntu VM is booted using EFI and nested ...
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Occasional packet loss between bridge interfaces
I have two virtualization servers based on libvirt and KVM. And sometimes I see packages get lost on one particular virtual machine. After restarting the virtualization host this problem is solved, ...
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Can I use OpenStack Rocky with a neoverse-n1?
Situation: For now, I'm stuck on OpenStack Rocky on Ubuntu 18.04.6 and I have some beefy Neoverse-n1 hardware (aarch64, 64-core, 1TB memory) to integrate. Can I accomplish this with on my current OS ...
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Virtualized Centos 7 on Ubuntu host: very slow I/O
I run a Centos 7 virtualized in Ubuntu 20.04. There is a huge I/O performance drop in the VM compared to the host. The host has plenty of RAM.
Host:
* MB/s = 1,000,000 bytes/s
* KB = 1000 bytes, KiB = ...
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Three virtio-blk devices crashing Windows 10 VM
If three virtio-blk devices are added VM is crashing in the middle of the Windows 10 boot. The attached blockdev has no influence. VM is working fine using two virtio-blk.
qemu-system-x86_64 \
...
-...
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Ping to/from KVM QEMU VM running in another network namespace
I cannot ping to the default network namespace from a KVM QEMU VM running in a separate network namespace.
Here is my setup:
ip netns add test-ns
# Creating veth
ip link add if-in-ns type veth peer ...
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How to create a shared Disk with the image stored on Host in KVM?
I am currently trying to setup a disk, using the raw img format on the host, which is then shared between multiple guest VMs (which are running Alpine Linux), using the libvirt / KVM virtualization ...
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Attach two network interfaces in a KVM guest to two VLANs in a physical switch through a single-interface host
I have installed a Debian-based VM with two network interfaces, one with one public IP and another with one private IP. I can access public gateway IP and beyond from the public interface (native/...
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Why are pci-devices passed as node and not by the parent
I was wondering why in every pci / gpu passthrought tutorial devices are passed by each node. Consider the following
+- pci_0000_40_03_1
| |
| +- pci_0000_41_00_0
| |
| +- ...
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How to read qemu fw_cfg value in windows guest?
Unable to find information about how to read -fw_cfg value in windows guest with the help of this: https://github.com/virtio-win/kvm-guest-drivers-windows/tree/master/fwcfg
Related question: https://...
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How to add two interfaces to KVM VM acting like a loopback
I have KVM machine with network interface (say eth0) attached to virbr0, I use it to ssh into the vm.
I would like to add two more ethernet interfaces (say eth1 and eth2) and "bridge it on the ...
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libvirt virsh not using a predefined target while attaching interface
I am trying to automate the process of creating a Guest VM. I am using uvt-kvm to create the VM. I am also taking a network type as a parameter. This can be either nat or macvtap.
Now in the script I ...
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QEMU Shared folder between Linux host and windows 10 Guest
I installed samba then I used the following command:
qemu-system-x86_64 -drive file=Windows.img,format=qcow2,if=virtio -nic user,id=nic0,smb=/home/aarav/Downloads
After starting up the VM, I opened ...
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How to convert virtual machine images to bootable OS installation?
I have a virtual machine installed in QEMU. I want to migrate this machine and use it as base machine. Query I have is that it is possible, and if yes will simple converting .img to .iso and burning ...
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Unable to access Internet from user-defined docker bridge network hosted on KVM
I am running Docker from a KVM:
Docker --- (hosted on) ----> KVM Guest ---- (hosted on) ----> KVM host
I created a docker bridge network with the following command:
docker create test
user@...
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Is it possible to use the IO priority from a KVM guest on the host?
When I use KVM with libvirt and virtio block devices, does it propagate IO priority in some way? If the guest starts a process with ioidle priority, I want it to run only if the host is also in ioidle ...
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KVM guest low network speed
I have a KVM guest VM running RHEL 8.7 (12vCPU, 24GB RAM) and a hypervisor with 10Gb NICs.
I'm getting weird results when using iperf3 on my guest machine as a client and a TrueNAS server as a server. ...
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qemu virtual machines slow during RAID5 check
Operating system: CentOS 7.9 (on both host and guests)
Host specs:
CPU - AMD EPYC 7502P 32-Core Processor
RAM - 250 GB (only 22G used by all VMs)
Disk - Four Samsung SSD 870 QVO 4TB, grouped in a ...
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QEMU boot with no progress for quite long after using the -enable-kvm option
I just wanna start a vm based on x86_64 via qemu, everything goes as expected(e.g. showing the console and login part) when I run the command below
qemu-system-x86_64 \
-nographic \
-smp 4 \
-kernel ~/...
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Physical/Bridge and KVM ports shows up even after unplugged the cable!
We have Debian 10, it has two physical interfaces which we bridge to KVM.
The issue I have is, when I shutdown the port from my virtual operating system or I disconnect the cable the birdge and ...
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KVM : What is the Maximum Number of Physical CPU and Physical Core KVM Can Support on a Single HOST
I am new here so this is my first day with a very confusing Quistion so please help me to understand it Properly. Expert Advise Required
My Quastion is :
I have a dell PowerEDGE Server With Intel ...
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slow performance on ssd when using kvm to launch vm's
On my host hardware I have 1G's speed
on my vm I create using kvm it drops to around 20MB's
My host is running ubuntu 22.04 LTS
How can I optimise this?
I am using file based VM's. I created disk ...
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Routing KVM VM traffic over wireguard from host OS
I'm trying to setup a Wireguard tunnel on my host OS and route all network traffic from a specific KVM VM over this Wireguard VPN. My KVM VMs are setup using bridged networking. The interface name on ...
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How to connect to VM from another computer in the local network
I have a host system (running Debian 11) where I installed a virtual machine (Ubuntu 22.04) using KVM. I can ssh between host and VM using their IPs (192.168.122.1 and 192.168.122.230). I also can ssh ...
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Migration disabled: vhost-user backend lacks VHOST_USER_PROTOCOL_F_LOG_SHMFD feature
I tried this command on the host.
virsh snapshot-create-as --domain test_vm_back --name "snapshot-before-install-package" --description "snapshot test"
As you know, this is just a ...
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libvirt live storage migration but keep vm on same host
Is libvirt capable of doing a live storage migration but keep the VM on the same host?
I have two NFS Network filesystem pools on one host. I would like to live migrate the underlying qcow2 disk files ...
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732
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Error starting domain: unsupported configuration: host doesn't support passthrough of host PCI devices - fedora 37
I added the section in the xml file of the VM win10 and I got the following error:
Error starting domain: unsupported configuration: host doesn't support passthrough of host PCI devices
when trying to ...
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1
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124
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Windows asking me to sign in with a company email?
Windows is asking me to sign in with my company's email, problem is I don't have one and nor is the company related to me whatsoever. I am trying to run Windows LTSC on QEMU. What gives?
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"Welcome to Intellek" when trying to install Windows LTSC 2021 in Qemu [duplicate]
On the "Account" stage, it says "Welcome to Intellek" and prompts me to enter my email for Intellek. I do not know what that is, a search reveals it is some company? I downloaded ...
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