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-...

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43 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 ...
3
votes
1answer
569 views

KVM guests are very slow after host upgrade to Debian Squeeze

Yesterday I upgraded a Debian Lenny server to Squeeze. This server hosts two KVM guests. One has run Debian Squeeze itself all along, the other was originally Debian Lenny, upgraded to Squeeze the day ...
2
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1answer
127 views

Routed bridge networking for KVM guests along with eth1 alias interfaces for shared hosting with dedicated IPs for each virtualhost

First question here on serverfault, so kind of a newbie, all feedback is welcome. I have a dedicated server running Debian GNU/Linux 8.4 (jessie) with one public IP and multiple additional public IPs ...
2
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1answer
71 views

How can I reconfigure a Linux guest in Proxmox to use a virtio-based HDD instead of IDE?

I'm running Proxmox 3.3.1 to host a virtual machine running Linux (64bit, kernel version 3.2.0). The virtual machine uses a 512GB HDD which was unfortunately configured to use the ide driver when ...
2
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1answer
441 views

Ubuntu 12.04.2 LTS Server - Randomly hangs with no logging

My server randomly hangs and becomes unresponsive without any logging (dmesg, syslog, kern.log, boot.log, and messages). I cannot predict when it is going to happen. Sometimes the server runs fine for ...
2
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1answer
2k views

Linux - KVM - very slow disk io

The I/O performance of my new server is pretty low. I Googled and tried everything I can imagine. First of all, here are the Hardware Components: AMD Opteron(tm) Processor 6344 4x Seagate ...
2
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1answer
136 views

Is the ethx mac address of a VM the same as the mac address of the corresponding tap interface?

I have a single node openstack install on an ubuntu machine. For some reason that I cannot figure out, the linuxbridge is dropping packets from this VM. My iptables seem to be fine (atleast as far as ...
2
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1answer
752 views

Why is there a socket interface on the host and a character device interface on the guest for virtio-serial?

I am trying to establish a communication channel between the host and one of its guest virtual machine using kvm as a hypervisor. For this, I am using virtio-serial. To create the virtual machine, I ...
2
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1answer
2k 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 ...
2
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1answer
845 views

capping VM IO with cgroups

I'm using cgroups to cap disk IO that a VM does by using libvirt's support for cgroups. So, I'm getting the major/minor number of the device from a 'ls -lL' on the drive where the '.img' file for the ...
2
votes
1answer
544 views

OpenNebula-managed libvirt not allowing access to /dev/kvm

I have a fresh Open Nebula 3.2.1 installation which I'm trying to get working and manage some freshly-installed debian squeeze kvm hosts. My problem is that when Open Nebula deploys VMs the KVM ...
2
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1answer
509 views

Setting up reverse proxy for virtual machines on HostOS

I am currently installing a server that consists of a Virtualization Host (kvm on ubuntu) and 7 VM's, some running MySQL and LDAP, others running different webservers and webapplications. The VMs ...
2
votes
1answer
648 views

Ubuntu Server mdadm drbd ocfs2 kvm hangs under heavy file reading

I have deployed four ubuntu 10.04 server. They are coupled two by two in a cluster scenario. on both sides we have software raid1 disks, drbd8 and OCFS2 and on top of it some kvm machines run with ...
2
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1answer
582 views

Installing and running a guest OS on KVM-qemu with only serial console access

I am trying to installing a bsd distro with virt-installer. With a Linux distro I used this: virt-install -n debian -r 1024 --vcpus=1 --accelerate -v --disk /var/kvm/installation-disks/debian.img,...
2
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1answer
847 views

Windows NT from vmware to kvm

I'm trying to convert a couple of old Windows NT virtual servers from vmware to KVM. I tried almost all guidelines and how to I found around the web but with no luck. I have the vmware virtual disk: ...
2
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1answer
251 views

KVM QEMU looses USB devices

I have a KVM Qemu setup. I'm mapping a USB device to a VM running windows vista. I get the device mapped, and all is well for some time. Suddenly the device disappears in Vista. If I do "lsusb" in ...
2
votes
1answer
435 views

iptables string match works on VM host but not guest

Have been tested some iptables string match rules on Linux KVM virtual machines with a bridged interface (Fedora 12 & 13 64-bit), for example a rule in the INPUT Chain that is before other port 80 ...
1
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1answer
15 views

KVM - Adding public IP over bridge

I am working on setting up a KVM environment and normally I just take it for granted that the networking has been set up. I am running into difficulty getting the public IPs accessible from the VMs. ...
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1answer
91 views

CentOS 7.2.1511 libvirt firewall configuration

I have a few CentOS7 setups in which I use iptables to forward ports from host to guests. Recently, i updated to 7.2.1511 and it seems libvirt insists firewalld to be active vs using iptables command ...
1
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1answer
78 views

virsh net-define for CoreOS cluster

I have a kvm/qemu/libvirt host with several VMs running happily on br0 with IP addresses that are in the same network as the host they run inside, 192.168.10.0/24. So I'm playing with CoreOS and ...
1
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1answer
51 views

Golden image updates in qemu

Consider that there are 100 windows virtual machines coming from a single base image and each vm is added to domain along with minor other machine specific settings which can be done by a script. ...
1
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1answer
22 views

Using byobu on KVM Guest via Serial Console

I am logged in to a KVM Guest (running Ubuntu 12.04 on Centos 6.6 host). I followed the instructions here Access pty login prompt in VM The problem is that the console fills the terminal window just ...
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1answer
670 views

Best options for KVM/qemu/libvirt VM migrations without shared storage

My team has recently been tasked with improving the virtualization infrastructure at the company and one thing we're looking into doing is speeding up migrations. We use local storage only on all VM ...
1
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1answer
61 views

Multiple public IPs routed via Cisco ASA to Proxmox VMs

I have a network with IP 199.221.2.136 (/29). I would like the Cisco ASA5505 [1] to work on .137 as router and use two public IPs (.138 and .139) on two VMs on a Proxmox server. Not sure how to route ...
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1answer
234 views

Creating a virtual network for KVM guests spanning multiple host machines

I have 5 physical machines running Ubuntu 14.04, all of them are together in a network. These all have static IP addresses. Each of these machines has 1 to 4 virtual machines via KVM/QEMU running ...
1
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1answer
63 views

Unable create/access storage pool in a KVM

I have trouble using storage pools in my KVM setup. I get the following error message whenever I try to use a pool-* command in my virsh shell. virsh # pool-list error: Failed to get the number of ...
1
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1answer
164 views

Create KVM storage pool using a ext4 formatted drive

I have a secondary hdd that I would like to use as a storage pool for my KVM host. Here is the xml file I use to create the storage pool, <pool type='disk'> <name>guest_images_disk<...
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1answer
300 views

CentOS Qemu+KVM lot of virtual machine processes

I am on host-machine with Centos 6.5, qemu+KVM and 2 virtual hosts in it (behind NAT). Both virtual hosts were configured with Virtual Machine Manager (one of them is with Windows 2003 and other with ...
1
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1answer
974 views

VPN SSTP windows client can not ping or connect to VPN server but it can talk to every other PC on the local LAN that VPN server is on

So I have an SSTP (with native Windows client) working fine in a sense. My windows client's local IP is 192.168.10.11 , so its local network is: 192.168.10.x The Remote VPN server is behind a router ...
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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 /dev/pts/...
1
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1answer
167 views

CentOS 6.5 Server Lockup

Today one of our CentOS 6.5 KVM nodes from OVH crashed after 46 days of uptime and we were unable to find the reason why, we had this issue before with the OVH kernel on another server but this one is ...
1
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1answer
556 views

Ping (DUP) with Linux bridges and tap devices

http://imgur.com/qPoy2QJ I have two Linux (Ubuntu 12.04) VM (running on KVM) that networked together using two Linux bridges as shown above. The network interfaces are Linux TAP devices. The problem ...
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1answer
223 views

kvm hypervisor kernel panic

My kvm hypervisor had been running with 20+ vps guests for a few months. But a few days ago it went to kernel panic. There were no abnormal operation that I found would cause the problem, except that ...
1
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1answer
192 views

Bridging is breaking the server: KVM configuration

I'm pretty new to networking and just can't get my head around this. I'm trying to setup KVM-Qemu so I can run some virtual machines. The instructions I'm following are telling me to use eth0 and ...
1
vote
1answer
521 views

kvm guest can not connect to outside of host, vice versa

I have a vmware vm running ubuntu 12.04 server(name=vmhost), with network bridged and full access to the internet. This vmhost is using the kvm hypervisor and is running a vm(centOS 6.4),network ...
1
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1answer
332 views

virt-viewer slower than virt-manager when viewing

I've got a thin client server in which I have a few VM's for users under KVM which I manage through virt-manager. What I've noticed is if I start a VM guest on a thin client using the command 'virt-...
1
vote
1answer
454 views

KVM Slow performance on XP Guest

The system is very slow to do anything, even browse a local folder, and CPU sits at 100% frequently. Guest is XP 32 bit. Host is Scientific Linux 6.2, Libvirt 0.10, Guest XP OS shows ACPI ...
1
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1answer
466 views

KVM bridge network initial setup - 2 public IPs

I have actually two problems with my server. The setup is like this: server in a data center connected directly to the internet one network card / two public IPs (one IP the server gets over DHCP, ...
1
vote
1answer
264 views

How can I tell what Hyper-V enlightenments a 2008R2 guest is using?

I have a Server 2008R2 guest running inside a KVM host. I've enabled various Hyper-V enlightenments through KVM (-cpu host,hv_relaxed,hv_vapic,hv_spinlocks=0x1000), but I'm not sure how I can confirm ...
1
vote
1answer
1k views

Proxmox - Assign more memory to KVM VM

Is it possible to assign more memory to a KVM virtual machine without restarting it? I changed the memory size of a VM using the Proxmox web interface, but can't see that increase in the guest.
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0answers
820 views

CentOS 6 KVM Host cannot connect to Internet while VMs can

I've configured a CentOS 6.4 server as a KVM host running multiple VMs. VMs running on this KVM host are fine. The problem is: the host itself cannot connect to the Internet. External addresses ...
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0answers
1k views

Apache bench failing with error “No route to host”

Got a new dedicated box. Installed CentOS 6.5 Installed KVM Installed a CentOS 6.5 guest rsync'd websites/database/settings etc over from existing VPS. Set up "dedi.mydomain.com" in DNS to test it ...
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0answers
3k views

“Network error: connection refused” when trying to SSH to guest VM

CentOS 6.5 host, CentOS 6.5 guest. Using kvm. VM gets a local IP from the virbr0 interface. I've set up some port forwarding in iptables. port 80 forward works, but my SSH forward does not. ...
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0answers
52 views

kvm guest cannot initialize network

I'm running a kvm ubuntu guest inside ubuntu both 12.04. Using KVM manager for this. Initially everything was fine, could connect from the guest to the internet, the host all right. But all of a ...
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0answers
1k views

Any disadvantage of running a virtual machine using files for its drives hosted on freenas/zfs?

I recently got tired of the really slow I/O reads and latency (10-30 MB/s read, not sure for latency but very slow) from a provider I rent a virtual machine from. He uses freenas, the virtual machine ...
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0answers
89 views

Forward connecting IP address to KVM guests

I'm running kvm with iptables configured to use DNAT and masquerading. However the guest machines are logging the host bridge ip not the connecting client IP address. Is there a way to configure ...
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0answers
3k views

KVM LVM-based guest… kernel: Buffer I/O error on device. Failing drive?

Currently setting up a small KVM host to run a few VMs for a small business. The server has 2 drives in software md RAID 1, then I have it set as a PV in an LVM setup. Guests and hosts are all CentOS ...
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0answers
12 views

Run same virtual machine twice simultaneously from the same base snapshot

I would like to have a base snapshot and then launch several virtual machines from it simultaneously. These machines have a short lifetime and then shutdown, there is no need to save the changed to ...
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0answers
22 views

KVM CPU features security risk or performance benefit

I need to run an untrusted VM with libvirt and KVM and need decent performance. When I run virsh capabilities to see what my CPU can provide, I get: <cpu> <arch>x86_64</arch&...