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, ...

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89 views

How to start a new instance of QEMU based on the same image and snapshot?

I have a QEMU image (qcow2) with a snapshot stored in it. Right now I'm using libvirt to start it. However, I want to be able to run more than one instance of the same image snapshot. I guess I can ...
0
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0answers
8 views

live-migration failure AND unable to launch an instance

I am having a trouble enablie live-migration in openstack. I follows the steps such as setting vnc_listen = 0.0.0.0 etc. ...
2
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2answers
2k views

Linux-on-Linux KVM: Which filesystem should I use for guest and host?

I'm in the process on playing around with KVM and setting up a linux on a linux-server, so I can reboot the (guest)server encrypt the rootFS of the guest without having to do initramfs-tricks to get ...
3
votes
1answer
58 views

What is fastest way to copy a sparse file? What method results in the smallest file?

BACKGROUND: I'm copying a sparse qcow2 VM image that is 200GB in size, but has 16GB of allocated blocks. I've tried various methods to copy this sparse file within the same server and have some ...
0
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2answers
64 views

Windows Server 2012 R2 doesn't find virtio drivers when installing on KVM

I'm trying to install Windows Server 2012 R2 on a Debian KVM host, but it does not seem to find the drivers. The guest has two drives attached: an install disk and the latest Windows virtio drivers ...
0
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1answer
68 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 ...
6
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1answer
11k views

KVM guest io is much slower than host io: is that normal?

I have a Qemu-KVM host system setup on CentOS 6.3. Four 1TB SATA HDDs working in Software RAID10. Guest CentOS 6.3 is installed on separate LVM. People say that they see guest performance almost equal ...
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1answer
2k views

Assign ipv6 address to KVM guests on bridge mode

System: CentOS 6.5 Network: Bridge on br0 IPv6: ISP Native /64 block. IPv4: ISP address (not internal LAN) Purpose: To assign IPv6 only to guests (manually), I don't want ipv4 address to be ...
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0answers
21 views

There is a kernel panic after every few months or weeks, with qemu-kvm tainted, VMs can't run. The machine needs to be rebooted

This is a heavily loaded KVM hypervisor node with ~90 windows 2K12 and win2K8 instances running on it. There are multiple machines with the same configuration and VMs are configured as highly ...
0
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1answer
45 views

How can I configure multiple tap interfaces for a single KVM virtual machine

I am trying to setup a VM using Linux KVM for a F5 BIG-IP VE deployment (used in a lab) ...
0
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0answers
10 views

RHEL KVM HA rgmanager

I have a RHEL HA 2 node cluster which is run with rgmanager, cman (corosync), clvmd, gfs2 and storage replication using drbd I let drbd, clvmd and gfs2 be managed by rgmanager, but i have 8 ...
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1answer
21 views

Revert libvirt external snapshot

Having some issues understanding how to revert snapshots on ubuntu 14.04 using KVM... Until now i have been using internal snapshots, however due to space issues (space not being re-allocated after ...
0
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1answer
42 views

KVM guest broken after taking snapshot

I needed to do some work on a KVM guest. To be able to go back to it's previous state, I took a snapshot: virsh snapshot-create vph-share After this, I tried to SSH into the VM: ssh ...
0
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1answer
29 views

State of VM after 'virsh save'

virsh save vm_name memdump and then virsh restore memdump restores a (running) VM all right. However, a VM is shut off after virsh save. I'm writing a "live" backup and restore script for KVM VMs, so ...
1
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1answer
1k views

How to make sysctl network bridge settings persist after a reboot?

I am setting up a notebook for software demo purpose. The machine has 8GB RAM, a Core i7 Intel CPU, a 128GB SSD, and runs Ubuntu 12.04 LTS 64bit. The notebook is used as a KVM host and runs a few KVM ...
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2answers
1k views

How can I change Qemu KVM machine architecture from 440fx to q35 with virsh edit or virt-manager

Still trying to get GPU passthrough working and decided to change machine type from older 440fx to q35 ie pc-q35 but if I do virsh edit on the config it refuse to save saying "PCI Bridges not ...
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5answers
2k views

Booting Ubuntu as VM with KVM on Ubuntu 12.04

I am trying to boot my very first VM using KVM. I have Ubuntu 12.04 installed, i made sure the BIOS had the right virtualization flag enabled for intel processor by running kvm-ok. I have researched ...
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0answers
63 views

SolusVM KVM-Virtualisation: Add IPs from multiple Subnets to VPS

I would like to add IPs from different networks to my SolusVM-KVM-Virtualisation. The virtualisation is working fine and is accessible via 81.95.3.xxx. But other IPs I added (82.199.134.xxx) are not ...
0
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1answer
957 views

dnsmasq(as DHCP server) isn't working in KVM+libvirt envirmont

I'm using dnsmasq as DHCP server in VM environment. But It didn't working. I disabled basic DHCP feature in libvirt. <network> <name>default</name> ...
0
votes
1answer
1k views

How to limit usb 2.0 port to work as usb 1.1 in ubuntu?

Ive got problem with kvm usb forwarding and printing (windows xp guest goes BSOD when i try to print something). Ive been adviced to change usb to 1.1 version. That only kvm works with 1.1 not 2.0 ...
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1answer
92 views

KVM unix socket file permission for VNC

I'm using kvm-qemu/libvirtd for a bunch of kvms. I'm using vnc for the graphical interface. By default, it listens on a tcp socket. I want to have it listen on a unix socket instead. Looking at some ...
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0answers
30 views

Vlan trunk between three switches and KVM Guests

I'am trying to find information regarding the appropriate configuration between three switches and KVM. More depth as per diagram. I need to create a tunnel for traffic created on sw1-port5 to be ...
0
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1answer
1k views

setting CPU cache size and model for KVM guest

Is there any possibility to create a custom CPU model for KVM Linux guests, or at least to modify parameters such as cache size and model name? I know I can set CPU features, topology and pinning and ...
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7answers
6k views

Get list of DHCP clients with KVM+libvirt?

I have several VMs running on Ubuntu 9.10 via KVM+libvirt. I want to be able to find out the IP address that has been assigned to each host without physically opening a physical "console" to each ...
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2answers
1k views

KVM: All network traffic to one guest (firewall)

I am currently using a VMWare ESXi 5.5 server for my virtualisation. The network setup is like this: PFSense firewall is the center of it all and connected to: LAN Network (physical NIC 1 assigned by ...
7
votes
1answer
610 views

kvm, vlans, how to simulate a 'mirror' port

I'm working with kvm 0.14.1 on an ubuntu lucid x64 box. I've got 3 vlans configured, one that is a bridge to the host's eth1. The others are host only. I want to start playing with snort. Is there ...
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0answers
31 views

CSR1000v image in Openstack as a VM

I have an esxi host. Under that I have created a Ubuntu 14.04 machine running Openstack(devstack single node)Juno release. I am trying to spin CSR1000v image as a VM inside Openstack. I followed the ...
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2answers
2k views

Resize Windows 7 Guest virtualised under KVM on Centos 6

I created a windows 7 virtual machine on Centos 6 running the following: virt-install --name=W7VIRT64 --ram=768 --disk path=/var/lib/libvirt/images/guest1-win7-32,size=8 --vnc --network ...
1
vote
2answers
74 views

Extremely slow qemu storage performance with qcow2 images

I'm running some images using libvrit on a small Openstack cluster. Storage performance on these machines is extremely poor: my monitoring tool shows 100% utilisation (usually on writes but sometimes ...
0
votes
1answer
49 views

Newbie to KVM/oVirt/ovs looking for clarity

I have some experience with vSphere, but am looking to get up and running with KVM. I've been looking at using oVirt as a VCenter type manager but, being new to all things ...
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2answers
1k views

KVM : virtual interface for virtual machine with external IP

I started using KVM, the network works fine under the bridge mode. But a wanted my Virtual Machine to have a external IP address, like XEN server where you can create a virtual interface for a VM and ...
0
votes
2answers
988 views

Converting raw image to LVM. Won't mount afterwards

According to this post, it should be okay, to use dd to convert a raw Xen image to LVM. What I have done dd if=/vm.img of=/dev/vg00/vm I can mount vm.img with mount -o loop vm.img /root/tmp. It ...
2
votes
2answers
47 views

How to measure boot time of a VM from host machine?

On both Guest machine and host machine, I am using Ubuntu 12.04. As a hypervisor I am using KVM. I want to perform some experiments related to boot-storm and I have created all other scripts to ...
0
votes
1answer
48 views

Networking in Linux KVM

I want to know if there is any way other than using linux bridges to interconnect interfaces from two virtual machines ? Since I am trying to run private spanning tree implementation in virtual ...
0
votes
1answer
1k views

apt-get update can not connect

i run a dedicated ubuntu 10.04 server. i use kvm/libvirt/virsh to run a virtual machine that's also ubuntu 10.04. i bridged the network (1 of 2 IPs is routed via NAT to the LAN, where my VM ...
0
votes
1answer
14 views

libvirt external snapshots: snapshot chain linked through filenames or inodes

If I have the following chain (it was created using external snapshots through virsh): base.qcow2 --> snap1 --> snap2[current] Now if I copy "base.qcow2" to a remote location, del the original ...
3
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4answers
1k views

Slow disk I/O in KVM with LVM and md raid5

I have been battling with a kvm setup under debian for two weeks now, specifically with guest I/O disk performance. The system: -Supermicro 1018d-73mtf (X10SL7-F motherboard) -16GB ECC/UB -Intel ...
1
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0answers
82 views

Access to equally defined VM in different VLANs

I have a working libvirt cluster and in order to perform some paralellization I have duplicated it. At the moment my scenario looks like this: two clusters whose VM definitions are exactly the same, ...
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votes
1answer
485 views

Install ProxMox AND cPanel [closed]

I'm in the process of upgrading our server to something much larger. This new server has CentOS and cPanel/WHM installed by default. My question is, is it possible to install a VM solution like ...
0
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0answers
37 views

Backup KVM running machine safely

I read some solutions to make backups of running VMs, but all take offline snapshots that seems difficult that will work if the VM has high I/O load. I have tested but i have doubts about the process ...
3
votes
2answers
3k views

set tap0 using virt-manager for bridged wireless

After 3 days I finally have kvm guests working on the network via wireless (link below - thanks!): My network is 192.168.1.0/24 on the host: sudo sh -c "echo 1 > /proc/sys/net/ipv4/ip_forward" ...
3
votes
1answer
1k views

Very poor disk performance on KVM node - mdadm raid10

For a long period of time, i'm experiencing performance issues on CentOS servers that are used for KVM virtualization. I'm running software RAID-10 with 4 disks (Seagate ST2000DM001, 2TB, 7200rpm ...
1
vote
1answer
62 views

How to backup running KVM guest qcow2 disk without LVM?

How to backup running KVM guests, when using qcow2 disks and host system does not use a LVM? Is it even possible without guest shutdown?
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0answers
15 views

KVM guest stuck connecting

EDIT: Disabling firewalld solved this for me I'm trying to set up a KVM host for a few small virtual machines. This is not production, just internal IT dept. stuff. My host OS is CentOS 7 with a ...
0
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2answers
66 views

KVM virt-clone while the VM is running

Is it possible to clone a running kvm machine without tools like virt-clone? They already have the original vm in production, I cannot shut it down. If I don't care about temporary data corruption ...
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0answers
43 views

How to configure and use qemu-guest-agent in Ubuntu 12.04? My main aim is to get the IP address of guest VM from Host machine

In the documentation it is not very clear that how to install and use qemu-guest-agent in Ubuntu 12.04. So can anyone help me out ? http://wiki.libvirt.org/page/Qemu_guest_agent It is a daemon ...
0
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0answers
34 views

netcat not listening on desired port

When I want to listen on desired port on one server, I use netcat ie: nc -l 8888 Then I can verify the server is actually listening on that port: netstat -tlnp | grep 8888 tcp 0 0 ...
2
votes
1answer
80 views

Pass an USB hub from a KVM host to a guest with libvirt

I have the following USB devices on a Linux server: # lsusb -t /: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci_hcd/2p, 480M |__ Port 1: Dev 2, If 0, Class=hub, Driver=hub/6p, 480M ...
17
votes
6answers
32k views

KVM Guest installed from console. But how to get to the guest's console?

I'm trying to install a fully virtualized guest (Fedora 14 x86_64) on KVM (RHEL 6), using command-line only (both hypervisor and guest). It goes without errors, and without a tangible result . I'd ...
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3answers
1k views

Windows Server 2012 on KVM on Ubuntu 14.04. Runs well for a while and then slows down

I have Windows Server 2012 Essentials running as a VM on KVM running on Ubuntu 14.04 LTS. It performs very nicely after a reboot but after a while it starts slowing down and getting sluggish. This ...