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Questions tagged [virtual-machines]

A virtual machine (VM) is a completely isolated guest operating system installation within a normal host operating system. It is a software implementation of a machine (i.e. a computer) that executes programs like a physical machine.

Modern virtual machines are implemented with either software emulation or hardware virtualization. In most cases, both are implemented together. Usually the term refers to system virtual machines which provide a complete system platform which supports the execution of a complete operating system (OS). Note that process virtual machine exist too, which are designed to run a single program (a single process).

An essential characteristic of a virtual machine is that the software running inside is limited to the resources and abstractions provided by the virtual machine—it cannot break out of its virtual environment.

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Backing up qcow2 kvm guests

I can't find any good info on backing up qcow2 kvm guests. I'm not really interested in the guests running state, only the file system. This question suggests using savevm but that creates a snapshot in place. I'd like to backup the filesystem…
EightyEight
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Any way to run Linux as a Virtual Machine on top of Windows so can have best of both worlds?

Since Linux has a lot of useful tools, while Windows has a lot of apps (like Chrome), instead of buying another machine to run Linux, is there a way to run it as a Virtual Machine on the PC? The Ubuntu installation CD-ROM doesn't seem to have such…
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Is it safe to run do-release-upgrade on a cloud VM?

I have a few Ubuntu VMs on Azure running Server 17.10 and I'm wondering if it's safe to upgrade them to 18.04.1 LTS using do-release-upgrade. If so, what precautions should I take?
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Why can't I ssh into (or even ping) my Ubuntu VM from the Mac OS X host?

I'm running Ubuntu 8.04 as a virtual machine using VMware Fusion 3.0 on Mac OS X 10.5.8. I want to be able to ssh into my VM from the Mac OS X host (so I can use MacFUSE and SSHFS to mount the VM's files on the Mac). I had this working previously,…
Daryl Spitzer
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KVM Host with 88 physical cores uses only 14 on 64 core Guest

I do have a server with 2 CPUs (22 Cores each plus HT). I created a KVM Guest with 64 allocated cores. When I run a compilation task the virtual machine shows all 64 cores at 100% (at moderate Disk I/O and memory usage) but on the physical machine…
HibikiTaisuna
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Windows Server 2008 R2 64-bit memory leak

I´m having trouble in one of my office servers. It´s a virtualized Windows 2008 R2 Server with 6GB RAM memory. It only has Microsoft SQL Server (memory assigned maximum = 3GB), and just a software that is not consuming more than 1GB RAM. However,…
Guillermo Zooby
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What happens when a physical machine fails in a virtual environment?

I'm getting started with virtualization so bear with me. In virtual environments applications run in a hypervisor's layer. So a single physical machine could have many virtual machines on it running multiple applications. So far so good? So what…
Sherif
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Can I run 64-bit VM guests on a 32-bit host?

Can I run 64-bit VM guests on a 32-bit host? If I have a physical PC with 32 bit can I launch a VM that is 64 bit? What virtual machine software (Virtual PC or VirtualBox or other) would allow this? I read out there that VMware may support this but…
Maestro1024
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Entropy on virtual machines

As you might know that it's not as easy to generate entropy on a virtual machine as on a "normal" pc. Generating a gpg-key on a virtual machine can take a while, even with the correct tools. There are plenty more crypto functions out there which…
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Are the free Win 7/8/10 VM's Microsoft provides for testing purposes restricted or any different than their counterparts?

Sorry for the poor title, I'll explain better here. Microsoft provides free Win 7/8/10 Enterprise VM's inorder to test modern browsers here: https://developer.microsoft.com/en-us/microsoft-edge/tools/vms/ I want to use the OS for something different…
Sad CRUD Developer
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Insufficient free space: X extents needed, but only Y available

I'm trying to extend a LVM in a Vmware Workstation 12 Pro CentOS VM. Below are the steps I am following and where I stopped because don't know how to folow from there: Create the primary partition using fdisk command Get partition table info using…
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Hot-remove memory in a Linux virtual machine

Linux supports hot-adding memory when running as a VM guest, in VMware for example. (Sometimes you need to manually inform the guest OS.) Is there a safe way to do the inverse operation — reducing the amount of memory allocated to a virtual machine,…
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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 supported"... by current qemu binary. What do I need to…
htfree
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What's the best file-system for storing virtual machine images?

I'm planning how to partition my hard drive. I want to have 2 partitions - one for Ubuntu, the main operating system, and the other for virtual machine images, as I want to run virtual machines of Windows and MacOS through VirtualBox. My question is…
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How to prevent IP spoofing using MAC and ebtables?

I am trying to create IP-MAC pairing rules in ebtables. There are few tutorials and related questions [1] available but I have kind of specific setting. ENVIRONMENT: I have many physical hosts. Each host has few ethernet cards, joined in bond and…
Martin
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