Virtualization: VMware, Xen, or VirtualBox?

All things being equal and VMware Server being free, why go with the alternatives? VMware's been doing this for a decade and they do it really well. None of the other projects are at the point where they are truly equal to the features or maturity that VMware provides. I say this not as a VMware Server user but as a Workstation user at home and an ESX user at work. I've often wondered the same thing but have never seen a compelling reason to leave the comfort of the warm, blue, partially-concentric squares ...

That being said, why did the vmware-server modules that used to be in Ubuntu disappear?

Disclaimer: I haven't worked much with VMWare, so I can't vouch whether you will miss any of its features following my advice ;)

I personally have been using VirtualBox, and am very happy with it. Performance is great, and installation is a breeze. It's got all the features I need, as in: clipboard integration, mounting iso images, snapshots, and probably a whole load I don't need.

I think you'd have the added benefit that you could run the same VM on both your OSes, which also means you can copy the VDI images between your OSes if you want to clone one of your environments. I actually make copies of my VDI to have "backups of a known-good state" (such as a clean and fully patched Windows install).

Anyway... I'm sure VMware will have more features, but whatever they are, I've personally never needed them.

"I think you'd have the added benefit that you could run the same VM on both your OSes"

VMware Server runs on both Windows and Linux so you can run the same VM's on both your OSes.

After using the free version of VMware for quite a while, I gave Microsoft Virtual PC a go.

I was fed-up of the VMware bloat, it seems to add on far too many services which I just don't want or need. So if you're running Windows as the host server then I'd give it a go at least, it's a free download.

As for Linux being a host server, it all depends on what your distribution supports - or whichever is easiest to add to your distribution. Virtualbox seems to have an apt repository which sounds convenient.

The problem with xen is, you have to use the Xen kernels. You can't use the distro kernels.

I was using it on my workstation at TiVo, and performance was decent. I took my old RHEL4 desktop and turned it into a Xen Domain underneath Ubuntu. Worked reasonably well, but X was lacking on the host.

I've been pretty happy with VMWare Fusion on my MBP for all sorts of VMs, FBSD, RHEL, Ubuntu, WindowsXP...

Totally depends on what the use of the virtualization is. If you're creating a bunch of linux systems to separate out services (dhcp, mail, web, etc) then xen might be the way to go. Testing on the desktop between windows/linux/etc, vmware is probably the way to go. Doing big enterprise stuff with high availability, disaster recovery, etc, vmware server / esx / Vi3 would be my guess (note: no experience with virtualbox here).

Each has their place I think, with vmware at least with an advantage as you can basically throw any x86 OS at it and it'll most likely work "out of the box" as it were. Course, the free vmware server can be a bit heavy (again, note no experience with virtualbox).

Xen is not like the other things. Basically consider Xen to be a way to virtualize Linux servers on a Linux server; yes, there's more possibilities than that, but just think of it that way for now.

Xen squeezes more performance out of the virtualization layer by throwing away the idea that it has to appear to be a generic PC. Instead, it pretends to be a very specific kind of PC-ish hardware which the "guest" operating system has to be written to run on. That means that the "host" (the virtualization layer) can rely on the "guest" knowing certain things, and the "guest" can take advantage of things that are useful for virtualization but which don't appear in a regular standalone PC. The tradeoff is that you can't just run anything as a guest.

So Xen is not what you want, I think.

As for the rest, I've used VMware Workstation and Server for ages and I've always been happy with it, but I also tried VirtualBox recently and was very pleased especially given the price. I'd probably try VirtualBox first if I were you because it's very low-investment to try it out.

Well I've used VMware, Parallels and VirtualBox on my Ubuntu machine. The truth is, I didn't like any of them... then again my machine is not the most expensive system, it is a 3 year of 64-bit AMD (running as 32-bit) system with only 1GB of RAM. Anyways... I also found that at this time most of the apps that I wanted on windows are working with Wine, so I stopped running VMs altogether. This all said, I stuck with VirtualBox primarily since it is free and it worked.

My main issue with virtual machines is that anytime you are running a second machine you are splitting your resources between two systems. I personally prefer the remote desktop/display idea, but that is not always available. I know that newer systems are supposed to be designed to handle VMs, but I still wouldn't expect a perfect solution. Also I've heard that in some cases, apps don't run as fast in a VM then in a native system, I know on Macs you run into issues sometimes with graphical apps needing to run in OpenGL modes since proper graphic drivers aren't available (may no longer be the case any more, not sure). So check out your apps before choosing a VM. This all said, I'll probably go VMware next time I need one, basically for the same reason Brian stated, experience is worth much more.

As for VMWare not being in the Ubuntu repository anymore... Looks like Canonical is no longer maintains the 'commercial' repository for Gusty onward. UbuntuGeek has a good help page though:
http://www.ubuntugeek.com/how-to-install-vmware-server-in-ubuntu-710-gutsy-gibbon.html

Xen paravirtualize, though 3.0 with Intel VT or AMD Pacifica will support full virtulization. Hence, if you are using < 3.0, Xen may be faster but you needed modified kernels.

VMWare does full virtualisation and being x86, this means more overhead but they have done some cool tricks to push this down to the bare minimum. Good thing is, it runs the normal kernels. I personally prefer that.

Choices, choices :)

Ah that would be VMware not VMWare. Trust me I have the T-shirts :-) Currently running VMware Fusion on a MacBook Pro, I've brought my last PC ever.

Like others said if it ain't broke don't fix it. Of course if Microsoft buys Yahoo you'll be (trying to) run Hyper-V.

Darryl

I work for Microsoft, so I'm biased :-) Hyper-V is really cool. I run it on my x64 laptops and workstations, and it works well.

From an architecture perspective, Xen is the closest to the Hyper-V in architecture (heck, they even both implement the same CIMv2-based management APIs), so that would be my fallback.

Qemu is the solution for you! I used to use VirtualBox, which runs great and fast (with Visat as well). But Qemu is less of a hassle to install and update. Just install GIT and pull the source, compile and install the OS from the CD. See here also for the few commands:
http://zdavatz.wordpress.com/2008/02/15/qemu-rocks-my-balls-of-oh-my-god/

XPpro runs great on Qemu. Qemu is best integrated with the Kernel.

I never used XEN except on Amazon EC2 services. No idea about VMWare.

best
Zeno

VMware Server has nice remoting - you can connect to the VM guest console from any other machine. You also don't have to have the guest VM console displayed anywhere for the guest to run.

I found VirtualBox's networking to be a nightmare. In VMware you can just accept defaults at install time and then click a few buttons to set host only/bridged/nat. For VirtualBox doing bridged is many pages of conflicting instructions, wacky shell scipts etc. (I have most stuff setup for PXE booting)

VMware Server is a poor product. I am a veteran in virtualisation industry and have spent 20 years in it, so I know for sure that they are way way behind the reality. Workstation is best but its too expensive so that is not an option. ESX 3.5 and ESX 3i too is way way too expensive so that does not fit in this picture anymore either.

Xen is free and so is Virtual Box, which is going to be a strong product from Sun as it develops further. Hyper-V too is a free product, even in production environment you barely pay a sum of $28.

So I'd advice you to go with VirtualBox as it is the best option in your case.

"That being said, why did the vmware-server modules that used to be in Ubuntu disappear?"

In Ubuntu 7.10, the following method works fine:

- Open /etc/apt/sources.list in your favourite text editor
- Uncomment the two 'partner' sources and save out the file
- Run 'apt-get update'
- Run 'apt-get install vmware-server'

Once you've agreed to the license pop-up and entered your serial number, job done.

"VMware Server is a poor product. I am a veteran in virtualisation industry and have spent 20 years in it, so I know for sure that they are way way behind the reality."

Care to elaborate? I'm interested in hearing what you have to say on the subject because well, I don't believe you. :-)

Since virtualization in the x86 world hasn't been around for twenty years, your experience is likely mainframe related, no?

"Workstation is best but its too expensive so that is not an option."

I personally prefer Workstation to server, but I think server would fit most people's needs. I've used Workstation since v1.0 back in 99 and it's just what I'm used to.
As for cost, it depends on what you classify as "expensive". It costs as much as a cheap PC and its limitations are only really as much as your physical hardware.

"ESX 3.5 and ESX 3i too is way way too expensive so that does not fit in this picture anymore either."

ESX really isn't a fair product to compare to VirtualBox or even the other VMware products. ESX has so many features a home user would never use (VMotion, VirtualCenter integration, etc.) Not to mention the hardware you'd have to buy to get the most out of it would also be prohibitively expensive for a home user.

Great question... If I can be so bold as to suggest that you consider taking a different approach, one you can do with any of the products above. Take a third box, put it on the network, and install the virtualization product(s) of your choice, then use remote management to handle your VMs.

On Linux, kvm/qemu beats everything else performance wise, for me.

I prefer VirtualBox because is easier then Xen or VMware to use.
I use Vmware converter to convert previous virtual machine that I created with VMware (http://www.valent-blog.eu/2007/09/16/vmware-converter/ in my language).
The converted VMs will be used on VirtualBox.
Favourites:
1. virtualBox
2. vmware
3. qemu+kvm
last => Xen
:)

I have used VMware Workstation on Linux for years both at home and at work, mainly to write and test crossplatform apps and occasionally to run the one stupid app that doesn't have a counterpart on Linux (I am in process of writing one now thus eliminating one more issue).

VMware Workstation works fine for the most part but there is always "oh crap, I'll have to rebuild it after I update the kernel" or after I update to the next version of whatever Linux distribution I run. Always have to look for the "any-any" patch or go into the driver code and fix it myself, google for fixes. VMware isn't any speed daemon when it comes to keeping pace with major Linux distros. I guess their main crowd is Windows (and seems to show, see a note below).

I just spent couple of days evaluating VMware Workstation 6.03 on my Ubuntu 8.04 host. It turns out it doesn't deal well with my Dell Inspiron 1505 with Core2 Duo. 2 of my 3 Linux guests (all Ubuntu, 7.04, 7.10, 8.04) are useless, in 7.10 I have no mouse, no keyboard, in 8.04 a single keystroke produces multiple characters - tough to type a password.
XP guest seems to run somewhat OK. On my desktop host, XP feels about the same as Linux guest. On the dual core laptop XP runs noticeably faster than the one working Linux guest I managed to install- hmmm, I wonder why. VMware seems to have a problem utilizing the dual core processors very well (WS 5.5.6 falls asleep on the Core2 laptop, rendering any guest machine totally useless (3+ hours to install XP, 10 minutes to boot it)). Also, giving both cores to the guest OS will slow it down to a crawl. And yes, as usual, installing the VMware tools croaks in 8.04 guest and you have to screw around with it.

Late at night I got frustrated to the point of asking myself "Do I really want to spend money to upgrade from my current WS 5.5.6?, do I really want to deal with this over and over and over?" and started looking for alternatives. And I stumbled on VirtualBox and this blog among others.

So I tried VirtualBox on both the laptop and desktop
Laptop host: Dell Inspiron E1505 Core2 T7200 @ 2GHz, Ubuntu 8.04, 2 GB memory, SATA drive (this is the Dell built and sold Ubuntu Linux machine)
Desktop host: My build 2.8GHz (runs at 3.06) Intel no HT single CPU, Ubuntu 8.04, 1 GB memory, SATA drive

First VirtualBox impressions:
1) It runs out of the box, 2 weeks after 8.04 came out, VirtualBox installs and runs on it flawlessly, no patches, no Googling for "how do I get this work?". Impressive.
2) Installation - didn't have to read documentation, installs flawlessly
3) It's 1/5th of the VMware WS (~21MB vs ~110 MB)
4) Guest OSs installs - flawless (7.04, 7.10, 8.04, XP) and fast - first time I noticed the speed difference
5) All guest OSs are *noticeably* faster and snappier - when at full screen I tend to forget whether I am in the host or the guest OS. Interesting - while XP does run faster than in VMware, Linux guests speed increased significantly.
6) VirtualBox seems to utilize dual core much better - statement based on my scientific method of observation of the CPU load gadget
7) It is very polished, Sun production quality
8) The documentation is very good
9) The product anticipates me doing stupid things and warns you of doing so before it lets you shoot yourself in the foot. It doesn't get in your way. Very well done. Very user friendly.
10) Installation of "Guest Additions" (counterpart to "VMware Tools") is, well, one more time - flawless, no code fixing necessary (first time I cracked open the docs, BTW)
11) Shared directories from the host work like a charm, are intuitive. This was another bit of black magic in WMware WS once in a while.
12) Networking, sound, CDROM, floppy, USB - all work out of the box, both the laptop and the desktop.

Drawbacks:
1) Tried to install DRDOS with limited success, looks like a problem with VirtualBox display. I was able to install DRDOS on VMware without a problem. Well, OK, I can play my 7th Guest on Dosbox just fine.
2) VMware WS hase a very nice tree based snapshot capability, VirtualBox seems to take linear snapshots only, no tree. It seems that this can be accomplished by cloning and subsequent snapshots of the clone. One just needs to be a bit more organized. Have to experiment a bit more here.
3) So far I have not succeeded in converting my VMware .vmdk XP Pro image to VirtualBox .vdi. Well, I converted it, it doesn't work :( - I may just bite the bullet and do a clean install (and probably having to deal with MS again, crap)

Final impressions: VMware WS feels clumsy and slow now when I got a taste of VirtualBox. Oh yes, there is a (documented) API? Way cool.

Conclusion: I *used* to like VMware a lot, YMMV.

Sorry for the long post, I just can hardly contain my excitement.

Jiri

it depends on what you want to do. for your windows host, i'd say keep it as is. virtualbox, qemu+kqemu, and vmware player ( probably server too ) are, when benchmarked, the exact same. they all use the same method of virtualization ( dynamic translation ) and are all limited to the same peak performance.

virtualbox does have support for for VT-x and AMD-V but last i checked ( version 1.5.8? pre-sun's takeover ) they said that they rarely used it since in some instances it is slower to use it than to use dynamic translation.

for your linux box. use either kvm (assuming you have vt-x or amd-v support) or virtualbox. virtualbox is plagued with the remake of the kernel module each time you change kernels but you can do "seamless windows" which lets your xp vm's desktop "merge" with your host's desktop ( take merge liberally, but it is really cool ). kvm, however, is quick and relatively easy to use.

xen with windows in domU, i have heard, is no better than kvm running windows. also, unless you have vt-x or amd-v, it'll be a pain to make a guest ( may be impossible, but i don't know that for sure ).

as for vmware for both situations. the free solutions aren't that great. virtualbox gives you the same kind of interface that vmware workstation gives you, i think, and is free.

I personally prefer the speed of VirtualBox, but so far I have encountered many issues with USB and sound drivers.

BTW, to convert from vmdk to vdi use Gparted: http://gparted.sourceforge.net/

1-Get the iso image, and mount it in the VM or VB as a cdrom.
2-Create a new VDI disk and add as secondary in VMware
3-Boot VM from CDROM
4-Use Gparted to reduce the size of the partition in vmdk disk if necessary
5-Copy partition from vmdk disk to vdi disk
6-Shutdown VM and change vdi to primary disk

I use virtualBox right now on Ubuntu 8.04 64 bit server host with win XP on the VM. It runs great.

I like vmware server but had no shared folders with the host.
That was v 1.0 though and v2.0 is supposed to have shared folders included.It also uses a web based interface which some people like and others don't. I haven't checked to see if it finally got out of beta.

Had problems with both as far as sound and usb but that is more of a problem with linux host because it can be fixed by adding an entry for usb to fstab file. The fix is in documentation at vmware and virtualBox sites.

Xen sounds pretty complicated so of course, I'm gonna try it out. Guess I'm a glutton for punishment. I'll probably be found on some forum in the next few days looking for help to fix my royaly messed up system.

VMWare does not work on Fedora linux. VirtualBox does.