linux-vserver is perfect for server purposes.
I think it would have been better to split the poll for server and desktop virtualization.

VirtualBox on the Desktop and Xen on the Server... I think would be two sub category. Nonetheless my vote is for VirtualBox, great desktop virtualization product.

Virtual Box is very good , i have using 2 years more and very simple to backup

Virtual Box is good but no matter what no1 can compete Vmware

Proxmox (uses KVM and OpenVZ depending). Can't vote twice

But I think Proxmox is for management only right? is like a webmin but for VM?

KVM. It's fast, easy to set up, and there are graphical tools if that's your thing.

I chose VirtualBox because I use it on several workstations, and often move guests about and run a couple of other operating systems in VMs while I'm working in my main Slackware environment.

It's a breeze to install (even on Wynd0z3), and yet....

I run several VMware farms, and at the enterprise level the HA and cloning, etc., is second to none... except that the vSphere client and vCenter are Wynd0z3 clients - not that you have to use them.

I also love KVM, and Xen is good too. For *self-managed* hosting I offer my clients KVM, which I can manage wit SolusVM and WHMCS without paying much attention at all - the same goes for OpenVZ, which works in a pinch and for non-mission critical enterprise applications will also do in a pinch for those who just want to run a basic binary based Linux distro - but it doesn't really bode all that well for distros that actually compile their packages from source when you install them - like Slackware and Gentoo.

Some people, when it comes to OpenVZ, like to say, "No Kernel, No Problem", but I see it more as, "No Brain, More Pain". Plus there's phenomenon of overselling which has permeated that market with many other service providers and the total lack of HA capability since you really must down the host for maintenance on a semi-regular basis.

So, for the purposes of this years poll, I once again chose VirtualBox. I prefer VMware, however, for serious stuff that I'm going to manage myself, and offer subscription self-managed hosting services with the KVM offerings.

I hope that helps!

Kindest regards,

.

VirtualBox here. I've only used VMWare in the past as an alternative but VirtualBox has been extremely reliable and fit all of my needs. I've even deployed it in a few small businesses and it's kept them running.

I'd say VMWare is actually the best, but I vote for VirtualBox because it is F(L)OSS and as a desktop virtualization solution it's practically as good as the proprietary VMWare Workstation. I quite liked qemu before, when it had kqemu it was comparable to VirtualBox, but nowadays I believe it is more important for its other emulation abilities.

Open source system-wide or supposedly "bare metal" virtualization solutions mostly disappoint me because they are dependent of a specific host OS (mostly Linux), because some of them are peculiar regarding the guest OS (again mostly Linux), and regarding the hardware (they require hardware virtualization to really work) and finally because of all that those are not real "bare metal" hypervisors. I'd say only the VMWare ESX family does its work as it should be (and by that I actually mean working as similar to IBM mainframes as possible, having a very thin and transparent hypervisor softeare). I'd say that a modified VirtualBox working on some minimalistic kernel would make a much better solution...

I am using 3 types of VMs since last 2 years:

Parallel Workstation - Fast to work with but you will not feel like working in a real complete OS. Because for some configurations you have to configure it in host and then it will reflect in the guest.

VMware - OK to use but host will be little slow.

Virtual Box - Ok to use but makes the host slow while working in guest.

So I will vote for Vmware .

I have also used KVM,QEMU but not that much . Will try.

And I think OpenVZ is also like Paralles Virtuzoo.

QEMU hit 1.0 at the end of 2011 which, from the change log, "merges the biggest difference between the qemu-kvm tree and upstream QEMU." It's good to see the work progressing toward a more unified code base.

Virtual Box Rocks

Most of the time playing with VirtualBox.

I'm hoping there is a VirtualBox port soon before Oracle closes the source and starts selling it.