Which OS Makes the Best VMWare Host?

astrojetsonjr asks: "A few days ago, Trillian_1138 asked about running Linux on a laptop. Yagu started a thread suggesting the use of VMWare to allow running multiple flavors of Linux and Windows at the same time. Lots of readers then posted their success stories using VMWare . My primary machine is an IBM laptop and I'm getting ready to move to using VMWare to allow me run Linux, Solaris and Windows at the same time. First, what is the OS/distro with which you have had the best success hosting VMWare? Finally, what host OS install and setup tips do suggest?"

Priorities first.

[Ant P.]

Pick whichever supports most of the physical hardware, since whatever it can't see the emulated OS can't either. If you're left with more than one choice there, narrow it down further depending on which matters to you more: speed, stability, security etc. Of course in a perfect world you wouldn't need to choose between those, but then you wouldn't need a virtual machine either.

Let me answer your question with a question

[El Cubano]

Which OS Makes the Best VMWare Host?

Why do you want to run VMWare? I have used both VMWare and qemu (as well as Xen, but I don't think that will work if you are interested in running Windows), and have found qemu to be the superior of the two. Sure, there is no built in GUI, but there are external 3rd party GUIs available if you want. Seriously, qemu makes networking much easier thatn VMWare does. No need to mess with modules (unless you want the accelerator, which I recommend), no need for services or daemons running like with VMWare. Additionally, it is open source, which I consider a huge plus. You can also emulate other CPUs. Want to emulate a PowerPC so that you can test compiling your app on FreeBSD on a PowerPC processor? How about Sparc? The *only* way in which I would see VMWare as being superior is if you are using one of their server consolidation products (GSX or ESX, I think). For workstation-level stuff, qemu is the way to go.

Don't forget coLinux

[spiritraveller]

If Windows is the host, coLinux [colinux.org] is a worthy solution. It runs almost as fast as a native install. And you can download a preconfigured Debian or Gentoo root image from the website.

Basically, it is a Linux kernel patched to run under Windows.

VMWare ESX

[danpat]

VMWare ESX runs without an underlying OS (it provides one of its own). It might be overkill for your needs though....

http://www.vmware.com/products/esx/ [vmware.com]

Depends on your hardware.

[CFD339]

VMWARE on Win32 will only be as stable as Win32 of course. So from that perspective, most people here would agree that Linux makes a better host.

On the other hand, if you're running a laptop or have some high end video or hard disk that requires drivers not available for linux, you may find your performance better under Windows (again, depending on many things, like how you configure vmware and its use of hardware).

There's no perfect answer to your question. My plans for new LAPTOPS will be to run the native drivers with Win32 as the host. Custom build desktops, however, I may well run the opposite way.

Linux and XFS

[jtatum]

I've run Workstation and GSX (Server) on Windows and Linux. The best performance by far was Linux with XFS. Ext3 does not cut it (regardless of writeback option used). XFS support is a little tricky to find in VMWare supported distros. For less critical servers, I prefer Centos 4 with the Centosplus kernel (see the Readme [centos.org]). Centos isn't supported by VMWare but Red Hat is.

VMWare Server supports Ubuntu as a host. It's a little easier to setup XFS and VMWare on Ubuntu. VMWare server claims experimental support for Ubuntu Dapper. I am running it on two servers for testing and it is performing very well. As Ubuntu gains popularity, the choice may be clearer. For right now, Google University has more help for VMWare on Red Hat^W^WCentos than Ubuntu.

If your system is AMD64/EM64T, you may be tempted to load a 64-bit OS. Resist the temptation. VMWare now claims official support for x64 host operating systems, but in practice these are more trouble to get working than they are worth (MUI, authentication, and even stability can be problematic IMO). With hardware that supports 64-bit virtualization (many new Pentiums and Opterons), 64-bit guests can be run on both 32- and 64-bit hosts. Determining whether your CPU supports it is so difficult, VMWare made a tool to do it for you called the processor check utility. (It's about halfway down this page [vmware.com].) Down the road when 4GB+ is standard on laptops, VMWare's x64 support will probably be a lot better.

Depends on what you need...

[ID10T5]

Having run VMware (I'm assuming workstation) on both Windows and Linux hosts, I have seen plusses on both.

VMware needs kernel hooks to provide its virtualization services. Under Linux, there are only a few supported Linux distros (and specific versions at that) that have pre-built modules installed as part of VMware. I run my personal VMware on an FC5 Linux host, and had to download an unsupported "patch" (from one of the VMware developers -- not even hosted on the VMware web site) to allow the vmware-config.pl script to build the necessary modules for my specific kernel. Every time I upgrade kernels, I must then rebuild the modules to get VMware working again. Also, under FC5 with SELinux enabled, I had to manually change the context of one of the VMware files after install before SELinux would even allow VMware to run. Under Windows, all of the above "just works".

Under Linux, I get better performance when running multiple VM's at the same time. I have had three 384MB VM's running at the same time, and because of memory management under Linux I only saw an increase of approximately 600MB vs. not running the VM's (no swap increase either). I also have better I/O performance as well. When installing the 3 VM's above, I had the CD's mapped to ISO files on the same disk that my VMware files were being created on. During the install, my load average was constantly around 15 and my system was definitely slower, but it was still functional. I have brought a Windows host (with enough memory to host both VM's fully in RAM -- no swapping) to its knees trying to install just 2 VM's simultaneously in the same way (ISO files on the same disk as the VMware files). It was so unresponsive, it took almost 5 minutes to bring up Task Manager to see what was going wrong -- and Task Manager didn't really show me what was wrong, just that the CPU was pegged and the VMware processes were doing all the work.

Re:Linux and XFS

[Trelane]

a word of warning about xfs: make sure you can always shutdown cleanly, or data loss and/or filesystem corruption can easily result. With that caveat in mind, however, XFS totally rocks.

Re:Don't forget coLinux

[spiritraveller]

The project is cool, but doesn't work very well and seems quite stale.

Worked great last time I used it, although the configuration involved editing text files.

The last release came out in February. That's recent enough to indicate that it's still being developed.

Re:Let me answer your question with a question

[Zephiris]

Don't forget that now with Qemu 0.8.1 and the 1.3.x-pre acceleration module, kernel-mode acceleration of the target is also supported.

Re:VMWare ESX

[swmccracken]

Does ESX Server Run on Linux? On Windows?
ESX Server runs natively on server hardware, without a host operating system. The ESX Server virtualization layer is a highly compact and efficient operating system kernel entirely developed by VMware for optimum virtual machine performance. This allows ESX Server to fully manage the hardware resources and provide the highest levels of security and performance isolation. ESX Server also incorporates a service console based on a Linux 2.4 kernel that is used to boot the ESX Server virtualization layer. It also runs ESX Server administration applications.

-- http://www.vmware.com/products/esx/faqs.html [vmware.com]

So, yeah, Linux might be used as the bootloader and/or system console image.

Re:Priorities first.

[Deorus]

> That's a bitch to get acceleration working in some, if not all, Linux distributions.

All ATi chips before and including the r250 (ranging from the RADEON 7000 to the RADEON 9250) have open source drivers bundled with Xorg and the Linux kernel. All other ATi chips can be used with the binary drivers from ATi. The thinkpads I know have RADEON MOBILITY 7500 chips, so they are perfectly supported.

> On the other hand, I run Debian on my T30, no acceleration on the video at all. It used to be working just fine, but somewhere along the way it stopped working and I never noticed it.

Maybe this is the right time to switch to Gentoo. ;-) And no, this is not a question of fanboyism, I'd just hard-guess (because I didn't bother to actually check) that Debian, Ubunto, and other dpkg/rpm based distributions are suffering from the same problem as the Kororaa Live CD [kororaa.org]: distributing precompiled binaries of the kernel modules required to load the ATi and nVidia drivers violates the GPL (a similar problem happened with the old Sun Java license which those distributions weren't allowed to support because they couldn't redistribute the software). On Gentoo the installation scripts and patches are completely independent from the distfiles thus allowing developers to provide portage support for software without redistributing it.

Debian

[metamatic]

VMware Workstation runs nicely under Debian Testing, with ReiserFS filesystem.

Re:I concur, but favor the Linux host

[nmullerny]

Here are two examples with empirical data to support them. Either the T41 is an extremely exceptional machine (It is nice, but I wouldn't go that far) or VMWare runs on both operating systems with what could be called "acceptable" results.
To get more accurate information you would have to look for (or perform) some well designed and run benchmarks. Determine which is your prefered Operating System. Also, find out if there are any functional limitations to VMWare on either of these platforms.
I have read in these replies about a number of limitations with VMWare running on both Linux and windows. Some I can confirm like having to run services for network support on windows (Is this really that bad?) and others I cannot such as not being able to use the high definiton VMWare graphics driver on Linux.

I have run VMWare on both operating systems for a while and although I consider it to be fully functional in both environments these are the things that I found to be worthy of mention:

VMWare on Linux Negatives :
1) To get the vmware-tools fully installed with the highres graphics and fast network support you must have the kernel source for your exact kernel. I know this will get me flamed but there are real people running distros that do not have the kernel source and do not know how to compile one.
2) There is no GUI tool to configure the virtual networks. This can be complicated, involving port forwarding for NAT networks, configuration of DHCP properties, assigning free IP addresses, etc. These are things that an experienced UNIX admin who is familiar with networking could do but many people will have trouble even with the provided documentation.
3) I experienced problems with the VMNET module on Slackware not being able to do anything but bridged networking. (I'm sure was a stupid thing but stumped me)

Negatives with Windows :
1) Umm. I'm sure there are some but I didn't notice anything worthy of mention. There is the fact that the network services have to run as services, but I don't consider this really a negative.

I think the most important factor to your decision is this: Linux support of your laptop's hardware. This is going to sound like I'm trying to scare you out of Linux on a Laptop but this is a purchase that deserves the level of consideration I will describe.
Find out as much information as you can about the available Linux support of the brand of laptop you are considering. Consider the brand of the laptop and the vendor and model of it's components. I know that there are several laptop oriented modules ("drivers") available to compile in the kernel. I remember power saving, CPU frequency management, battery management, and more. But laptops often have many vendor specific hardware devices and system management software and something may not be supported.
You should research what hardware features are important to you and if they are supported in Linux. Also find out what system management sofware the vendor provides and see if there are equivalents in Linux. An example of management software would be a program that allows you to control energy consumption when plugged in vs when running on battery.
Make sure the manufacturer of the various laptop devices have "drivers" for linux. Check things like the Ethernet card (even if it's builtin), modem, infrared (if you use), sound device, video device, USB device, 1394 device, and card readers. If you do find a problem remember that many of these devices can be replaced with a PCMCIA device that does the same job.
You want to check things that you'd think should not be a problem like the CD/DVD reader/burner. If linux has a problem with making the CD hardware work the you are in trouble. It is probably unlikely that the vendor has an alternative brand of reader that can be used. And do you want to lug around an external USB drive?
Don't get distracted by the unimportan

Re:Don't forget coLinux

[LoveTheIRS]

Pragmatically, colinux hasn't needed any new updates. The only feature missing is native X support, and it has been taking a very long time to get that done. Colinux works fine for any non-gui purposes in it's current form.