Questions tagged [virtualization]

Virtualization is the creation of a virtual (rather than actual) version of something, such as a hardware platform, operating system, a storage device or network resources

Virtualization is the creation of a virtual (rather than actual) version of something, such as a hardware platform, operating system, a storage device or network resources.

Virtualization helps in:

  1. Better use of under-utilized computers
  2. Hardware Independence
  3. Data protection

I) Virtualization can be done at zonal level, software or hardware.

The main reason for server virtualization is to maximize the utilization of resources. In the conventional system each application will have its own dedicated server. The drawback is that most of the resources remain unused most of the time. Typically, less than 20% of a physical server resource gets utilized. Companies still need to spend money, energy and resources for updating each of these physical servers and keeping them up and running. Virtualization divides each of the physical servers into multiple virtual servers, thus creating multiple logical instances of software on a single physical hardware. Thus multiple applications can run on a single server and each application running on a virtual server is made to feel that it is the unique holder of the physical resource. Thus it maximizes resource utilization and reduces the cost of maintenance by reducing the number of physical servers.

II) Network Virtualization: Given a physical network, virtualization allows for multiple logical networks to run atop(parallely) the common physical substrate. Thus, multiple users can share the network resources and it provides a secure/ reliable connection among the virtually connected nodes.

2317 questions
3957
votes
21 answers

How is Docker different from a virtual machine?

I keep rereading the Docker documentation to try to understand the difference between Docker and a full VM. How does it manage to provide a full filesystem, isolated networking environment, etc. without being as heavy? Why is deploying software to a…
zslayton
  • 45,810
  • 9
  • 33
  • 48
139
votes
3 answers

Cross-browser testing: All major browsers on ONE machine

Aim of this guide: Running multiple unmodified native versions of Internet Explorer, Safari, Opera, Chrome and Firefox on a single machine, side-by-side. Covered in part 1: Table of contents Which browsers have to be tested? How to create a…
Rob W
  • 315,396
  • 71
  • 752
  • 644
127
votes
3 answers

Virtualizing an ItemsControl?

I have an ItemsControl containing a list of data that I would like to virtualize, however VirtualizingStackPanel.IsVirtualizing="True" does not seem to work with an ItemsControl. Is this really the case or is there another way of doing this that I…
Rachel
  • 122,023
  • 59
  • 287
  • 465
113
votes
5 answers

What are the differences between virtual memory and physical memory?

I am often confused with the concept of virtualization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process? Where does this virtual memory stand when the process (program) from the…
103
votes
4 answers

What is the difference between the Intel x86 Atom and Atom_64 system images?

I am using the Android SDK Manager to install the system image for the Android M Preview. However, I noticed that there are two separate images for the x86 platform. What are the differences between the two and which one should I select for my…
Nathan Osman
  • 63,773
  • 66
  • 242
  • 344
96
votes
2 answers

VirtualBox and vmdk vmx files

I've seen people on the net offering images of a particular Linux setup, and they offer it as either VMDK/VMX files or ISO files. Now an ISO seems to work with VirtualBox, because I can tell it to mount a CD/DVD drive and use the ISO instead of a…
LoveMeSomeCode
  • 3,718
  • 7
  • 30
  • 45
90
votes
10 answers

Can I run a 64-bit VMware image on a 32-bit machine?

Can I run a 64-bit VMware image on a 32-bit machine? I've googled this, but there doesn't seem to be a conclusive answer. I know that it would have to be completely emulated and would run like a dog - but slow performance isn't necessarily an issue…
John Sibly
  • 21,309
  • 7
  • 55
  • 78
70
votes
16 answers

Detect virtualized OS from an application?

I need to detect whether my application is running within a virtualized OS instance or not. I've found an article with some useful information on the topic. The same article appears in multiple places, I'm unsure of the original source. VMware…
DGentry
  • 15,552
  • 7
  • 48
  • 65
70
votes
11 answers

How do I delete a virtualbox machine in the GURU_MEDITATION error state?

How do I delete a VirtualBox machine in the GURU_MEDITATION error state? Is it enough just to delete the directory while VirtualBox is not running? EDIT: After posting, I deleted the entire directory that "Show in File Manager" navigates to. It…
Matthew Flaschen
  • 255,933
  • 45
  • 489
  • 528
69
votes
10 answers

Virtualbox enable nested vtx/amd-v greyed out

On my Ubuntu 18.04, I've installed VirtualBox 6.0 in order to have nested virtualization. Virtualization is enabled in my bios. However, when I open the settings of my (powered off) virtual machine and go to System -> Processor, the option "Enable…
Francesco Borzi
  • 37,945
  • 31
  • 126
  • 195
69
votes
2 answers

What is the difference between Full, Para and Hardware assisted virtualization?

I am going through the topic of virtualization, it seems a bit silly to ask this question but i am totally sucked up understanding the basic concept, Wikipedia does provide some relevant information, but it is not good enough for me to understand…
Muhammad Faraz
  • 3,649
  • 6
  • 26
  • 45
68
votes
1 answer

Do x86 instructions require their own encoding as well as all of their arguments to be present in memory at the same time?

I am trying to figure out whether it is possible to run a Linux VM whose RAM is only backed by a single physical page. To simulate this, I modified the nested page fault handler in KVM to remove the present bit from all nested page table (NPT)…
savvybug
  • 783
  • 2
  • 6
67
votes
2 answers

What's the differences between Xen, QEMU and KVM?

I know QEMU is used by Xen, and KVM is a fork of QEMU. So, KVM includes that Xen adds to QEMU ? What is the name ? Thanks
Xorax
  • 1,486
  • 2
  • 16
  • 18
66
votes
7 answers

How to convert flat raw disk image to vmdk for virtualbox or vmplayer?

I have some old images of old Linux filesystems in flat file format. they can be used by Bochs, but I need to run them with Virtual Box. Virtual Box cannot use images in this format, so I need to convert these images from flat file to .vmdk file…
okutane
  • 12,699
  • 9
  • 54
  • 65
64
votes
1 answer

Live Binding with Automatic updates in XE3 (no need to call Notify() as in XE2)

I am currently using Delphi XE2, and heard about their new Live Binding with Automatic updates in XE3 (no need to call Notify() as in XE2). in C# or in Delphi XE2 we have to implement INotifyPropertyChanged (Notify(); in Delphi), and this approach…
VibeeshanRC
  • 6,659
  • 8
  • 50
  • 97
1
2 3
99 100