Virtualization is the process of using software to create a virtual resource of something; usually, it refers to hardware virtualization, the act of running an operating system (referred to as guest) inside an host system.

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130
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16answers
34k views

Any reason NOT to run Linux in a VM all the time?

I've switched to using Arch Linux for most of my day to day work and don't need Windows for anything but gaming and the couple of apps that aren't ported to Linux like OneNote. My Linux distro is ...
38
votes
3answers
28k views

Does LVM impact performance?

I have to migrate a few servers to Linux, and one important aspect that I need to evaluate is that my new host system must have elastic storage capacity. Naturally, doing some basic research, I came ...
29
votes
7answers
3k views

Easy way to determine virtualization technology

I have command line access to a Linux machine which may or may not be virtualized. I want to determine what kind of virtualization technology it runs on, if any (VMWare, VirtualBox, KVM, OpenVZ, Xen, ...
10
votes
4answers
2k views

Lightweight isolated linux environment

I want an isolated (guest) Linux environment on my computer that I can mess up without worrying about the host. E.g. install a lot of stuff from source without package management, pollute environment ...
9
votes
2answers
1k views

Tools for Monitoring Steal Time (st)

We're running on a virtual "dedicated" server, which should, in theory, mean that we're the only guys on the server. In practice.... I'm thinking we might not be. Notice that although it looks ...
9
votes
7answers
9k views

Should LVM partitions be used in virtual machine images?

Should LVM be used for the partitions when creating VM images (e.g., KVM images)? It seems like it adds complexity if you want to, say, mount a qcow2 image in the host if the image has LVM partitions. ...
8
votes
1answer
634 views

Lightweight virtualization on Linux with user isolation

What Linux-on-Linux virtualization technologies provide user isolation? Specifically, I want root in the virtual machine not to have any privilege on the host. This was not the case for LXC, but was ...
7
votes
1answer
10k views

Do VirtualBox or VMWare use the Intel VT-d feature?

I'm thinking about a new laptop, which has Intel VT support, but recently I discovered a feature other than IntelĀ® Virtualization Technology (VT-x), which is IntelĀ® Virtualization Technology for ...
6
votes
2answers
3k views

Fast X for LXC guest on localhost?

How can I run X apps inside an LXC container efficiently? ssh -Y guest is too slow - there is no graphics acceleration with ssh -Y - everything has to travel over the virtual network with the ...
6
votes
1answer
755 views

Creating VLANs between network namespaces

I want to implement the topology shown in the figure below using network namespaces (ns1 to ns4). ...
5
votes
8answers
2k views

WebGUI for Virtualization?

Are there any virtualizations that can be accessed via a WebGUI too? I mean the administration part is enough on a terminal, but we need a virtualization/webgui solution for "customers". So that ...
5
votes
1answer
1k views

Does quiesce exist for Linux?

Quiescing a file system allows you to make a backup of the database while it is still running and other programs and their data as well. The application generally needs to be notified of the quiesce ...
5
votes
6answers
295 views

How can I be sure that my server is not virtualised?

How can I make sure that my Linux server is running on a non-virtualised real box? This is the scenario I am thinking of: I install some distro on a rack-mounted server, I rent some rack space on ...
5
votes
1answer
2k views

Linux LXC vs FreeBSD jail

Are there any notable differences between LXC (Linux containers) and FreeBSD's jails in terms of security, stability & performance? On first look, both approaches look very similar.
5
votes
1answer
194 views

Running one OS per core

I'm interested in using a COTS board like the Wandboard for a project. On one hand I'd like to use something like Ubuntu for user interaction, sounds, TCP/IP stuff, etc. But I also need an RTOS like ...
4
votes
3answers
4k views

“echo 3 > /proc/sys/vm/drop_caches” - Permission denied as root

I am currently having some issues with the cache. It is a little too much right now so I wanted to clear it. I googled and found this little command: sync && echo 3 > ...
4
votes
3answers
521 views

Can libvirt check if virtual machine is fully booted? Can another tool?

I currently have small VM to do certain tests (it has multiple benefits - like testing on another distribution, Fedora 15, as well as running make distcheck without the problem of polluting /). ...
4
votes
2answers
1k views

Openstack for home cloud hosting

I am experimenting with a couple of technologies that I soon may have to use at work. So for now, I was thinking about duplicating the environment which I may have to create for my office at home so ...
4
votes
2answers
6k views

How to find VM OS installation media file in the Proxmox Web Interface?

I have installed Proxmox and wanted to create a VM by using the Proxmox web interface GUI (now the version is 2.0-38/af81df02) However I have problem to find my Guest VM OS installation CD/DVD ISO ...
4
votes
2answers
2k views

CPU usage of KVM

I have a linux host with 4 KVM linux guests. All the guest are pretty much idle, having a load of <0.1 inside the guest. Now, if I do a top on the host, each KVM process is using something about ...
4
votes
2answers
723 views

VM benchmark tools?

I would like to benchmark of few XEN-constallations: PV DomU HVM DomU with PV network and disk drivers HVM DomU with emulated IDE and PV network The base will be the same VM with the same ...
4
votes
2answers
83 views

How to set up interchangeable VM guest/hosts

I'm looking for a way to set up a computer so that the disk is partitioned for multi-booting to two operating systems: Linux and Windows. Whichever one is booted, I want the other to be accessible as ...
4
votes
1answer
1k views

kvm doesn't load Windows 8

I'm launching kvm with the following parameter: kvm -m 2g -smp ncores=2 -hda disk.img -cdrom win8.iso My CPU has VT support and enabled, EDIT I seems to have limited emulate type: pc ...
4
votes
1answer
839 views

One host, two virtual machines that cannot ping each other. How to solve

We have Virtual Machines operating within the KVM environment. We setup one as a dev server running Apache etc., and the other as a Windows development environment. The two environments are setup ...
3
votes
4answers
373 views

How can I zero files out inside a VMware image file so that their space can be reclaimed?

is there a command on Linux to remove a file but zeroing it's contents first? so if i do, something like this: rm -rf /var/cache/pacman/pkg/* it would overwrite each file on that directory with 0 ...
3
votes
2answers
3k views

Are there any virtualization solutions for OpenBSD that aren't from ports?

I'm searching for a virtualization solutions for an OpenBSD host and a CentOS guest. What are my options? I'm searching for one that doesn't use packages from ports. Are there any?
3
votes
2answers
1k views

How to force the time and date settings to refresh from the internet?

I'm running Ubuntu 12.04 LTS under vmWare. When I restart a suspended image, the system clock doesn't detect that the system time is out of date. In the Time and Date settings dialog, I've selected ...
3
votes
2answers
43 views

Running -march optimized software on another architechture?

I'm running an Athlon64 server with LFS and would like to have a local copy of the server in a virtual machine for testing purposes and building software. My PC uses an i7 and the existing server ...
3
votes
3answers
502 views

Problem with mount namespaces under Fedora

I've run into an odd problem regarding mount namespaces on Linux. I have two systems, both X86_64 running kernel 3.2.3-2 under Fedora 16. I am attempting to mount a tmpfs filesystem in a child ...
3
votes
2answers
264 views

Terminal-based (non GUI) virtual-computer program?

Are there any terminal-based (ie. non-GUI) virtual-computer programs out there? I've been using programs like VirtualBox and QEMU, but they're obviously GUI-based... I was hoping for a virtual PC ...
3
votes
1answer
367 views

Emulate unplugging a network cable with qemu-kvm

[Background: I'd like to actually test How to take down a static network interface when not connected? ] I'm setting up a QEMU-KVM virtual machine using libvirt (via virt-manager). I put two NICs on ...
3
votes
2answers
295 views

Prevent hacking the grub.conf using a 'live rescue' from a live linux iso

It happened that I had set the grub password in grub.conf. But, using a live linux iso, I was able to delete the password from the grub.conf. Please read the steps for the same mentioned in this link: ...
3
votes
2answers
53 views

LiveCD “Remembers” Earlier Partitioning

Whenever I use VirtualBox to install a Linux distro, I usually install the LiveISO onto the hard drive instead of just using it as a live CD. However, sometimes the ISO doesn't install fully (usually ...
3
votes
1answer
5 views

Real-time executive approach, can be run in desktop Linux?

With the real-time executive approach, a small real-time kernel coexists with the Linux kernel. This real-time core uses a simple real-time executive that runs the non-real-time Linux kernel as its ...
3
votes
1answer
49 views

memory buffering in virtual machines

Is there any point to doing disk buffer caching in a virtual machine, if the hypervisor OS is doing it? I wonder if buffering in the VM will just waste memory that could be better allocated to VM use, ...
3
votes
2answers
525 views

Does FreeBSD support network virtualization like Crossbow?

Does FreeBSD support network virtualization like Solaris Crossbow? I've tried to follow the VImage links from the FreeBSD wiki page, but the links are mostly dead. If VImage is no longer part of ...
3
votes
1answer
229 views

Custom live distro - ways to detect it is running inside virtual machine (or prevent running in VM altogether)

I am creating a custom live distro that will be a specialist work environment for those of my employees that are on the road. I am looking for ways to detect or, ideally, prevent my live distro from ...
3
votes
1answer
268 views

X and xdotool in LXC instead of KVM

So far I am using various xautomation/xdotool scripts in a KVM virtual machine (linux guest) in order to let them do their work and let me work uninterruptedly. I am using a VirtIO disk, but still the ...
3
votes
2answers
427 views

How to add a ms-dos partition table to a loop device?

I recently made a dd from a disk partition. I want to use it as a disk in a virtual machine. I can't because the disk has no partition table. Can I had a partition table to a loop device? how? ...
3
votes
2answers
3k views

Mouting a kvm qemu disk image with multiple partitions

I am trying to mount a KVM-qemu disk image with this command: sudo mount -o loop,offset=32256 centos6.img /mnt/centos6. But it shows this error: you must specify filesystem type. As I have more ...
3
votes
2answers
51 views

How can I force chrooted programs to use a virtual ethernet device?

First off, this is not for security reasons, or for use in a production environment. It's because I want to mess around with different configuration management systems on relatively low-spec ...
3
votes
0answers
1k views

PCI passthrough with Xen

I am trying to run Windows XP in a Xen DomU virtual machine with a PCIe device, for which there are no Linux drivers, being passed through from a Debian Squeeze Dom0. My hardware supports ...
3
votes
0answers
189 views

Setup Cloudmin on Centos installed in LVM

I installed CentOS 6 with default LVM partition pattern. according to this pattern Can I use Cloudmin and store KVM Disks in LVM as Logical Volume? I think Cloudmin requires creating new logical ...
3
votes
1answer
619 views

Xen domU fails to start with kernel panic

My dom0 is Gento 3.3.2, the kernel is compiled with Xen support. And I am planing to use the same kernel to boot my domU. This is my domU configuration file: 1 vif = [ 'bridge=xenbr0' ] 2 vcpus ...
2
votes
2answers
379 views

Solaris11: Alternative to xVM Hypervisor?

AFAIK, support for the xVM Hypervisor - basically Xen - has been dropped in Solaris 11. Is there an alternative/replacement for it? How does it compare to Xen? Obviously there is zones if you want ...
2
votes
2answers
1k views

Installing Freebsd as guest OS on kvm without using VNC

I want to run Freebsd as a guest OS on kVM running on Ubuntu server 10.04. All howtos mention VNC as a necessity to start and finish the installation process. Can I install freebsd on kVM without ...
2
votes
1answer
799 views

How to achieve the effect of chroot in userspace in Linux (without being root)?

The goal is to install and run programs in a displaced (relocated) distro (whose / must not coincide with the global /) inside a host Linux system. The programs are not adapted for using a different / ...
2
votes
2answers
242 views

Can I have a bridged interface without an IP?

I have 2 NICs: eth0 & eth1 on a host OS which runs some VMs (LXC) under it. The hosts eth0 is connected to a private network and configured as the primary interface. The hosts eth1 is connected ...
2
votes
2answers
802 views

Wireless bridged networking in KVM. Why is it so complicated?

I've been using VirtualBox (and sometimes VMWare) for years and I've never had any problem with the virtual network adapters, no matter if the physical ones were wired or not. I also played some time ...
2
votes
1answer
440 views

Virtualbox under Proxmox

On a Jenkins Master-Slave configuration and need to run on the slaves Kitchen tests on several jobs. Kitchen for those who do not know it, runs infrastructure on demand using Vagrant and VirtualBox ...