Linux

Demystifying virtual machines

Virtual machines that allow a user to run Windows from within Linux are starting to catch on. Let Tim Lee get you up to speed on what's what.

On May 16th Tim Lee, CEO of BuyPogo.com, explained virtual machines. These ‘machines’ allow users to run Windows from within Linux. Virtual machines are gaining in popularity because users want to try Linux while retaining their old Windows applications. If you couldn’t join us then, enjoy the transcript and we hope to see you on our next live Guild Meeting.

On May 16th Tim Lee, CEO of BuyPogo.com, explained virtual machines. These ‘machines’ allow users to run Windows from within Linux. Virtual machines are gaining in popularity because users want to try Linux while retaining all their old Windows applications. If you couldn’t join us then, enjoy the transcript and we hope to see you on our next live Guild Meeting.

Note: TechProGuild edits Guild Meeting transcripts for clarity.

Welcome to the Guild Meeting!
MODERATOR: In tonight's meeting, Tim will answer any questions you may have about "Demystifying the Virtual Machine." As an extra incentive, tonight's most active chatter will receive, compliments of Tim, an ASUS K7M motherboard (minus CPU) valued at $159!

PSCHUVIE: Tim, how about a little overview of how you are using virtual machines in your operation?

TIM LEE: We're currently partners with VMWare as their only OEM partner bundling their software with our hardware solutions. Basically, we're using virtual machines to allow our customers to use Windows and Linux at the same time.

DALE: How effective is VM?

PSCHUVIE: What exactly is a VM and what do you see as the advantages?

JSZADA: What would be the advantages of using both operating systems at the same time?

TIM LEE: A virtual machine is exactly what the name suggests. It is an environment which allows you to treat it as a separate machine. The advantages are that you can seamlessly go from one OS to another.

JSZADA: What type of GUI does the user see?

DALE: As one who comes from an NT domain and uses Outlook, I can see the potential, but are there other apps out there that will work with Outlook?

TIM LEE: This is especially helpful in development environments and also in tech support environments. A tech support engineer getting a call from a guy with a P3-800 running 256 MB of RAM and Linux can easily use a virtual machine to create the customer's machine without having to build that machine.

Give it the reboot
MIKKILUSA: So do you need to reboot to switch?

JSZADA: Excellent idea for development and tech support.

TIM LEE: There's no special guy. In our Winux systems, you boot up Linux first, then you double-click on an icon on the desktop that turns on Windows. A window pops up and inside that window you see Win98 booting up.

JSZADA: How difficult was it to cross-reference the two different systems to allow that to happen?

TIM LEE: No you don't need to reboot to switch. That’s the beauty of it!

DALE: Isn't VMWare a little pricey?

TIM LEE: It's not very difficult at all. It's very seamless to set up.

JSZADA: Where does the software reside to do it?

TIM LEE: Well, VMWare is $99 for home users, which is reasonably priced. There's another company (shoot forgot the name) that does PC emulation on a Mac and they charge several hundred dollars.

DALE: Price isn't that bad. What about us corporate users?

TIM LEE: The VM software resides on the Linux partition.

DALE: Does VMWare have a per user seat price?

PSCHUVIE: Interesting that you say home user when most of them have hard enough time with one machine let alone adding a virtual one.

VMWare prices
TIM LEE: Corporate users pay $300. Those are VMWare's prices. There's a long-standing open source project called "Freeware" which will be free. Does the same thing.

RICKENGELHARDT: If you're running basically in a window, how’s that affect apps running in different VM within windows i.e. 16 bit vs. 32 bit apps?

TIM LEE: Some home users have numerous machines (1 Mac, 1 PC, 1 NT, 1 Linux). A virtual machine running all of those can solve cross-platform issues.

DALE: I for one could use something like that. $300 isn't out of line.

JSZADA: How much space is required on the HDD?

TIM LEE: 32 bit and 16 bit apps don't see any additional differences in speed/efficiency. Remember, a virtual machine is a real environment. It's as if that little window is just another machine.

TIM LEE: Ideally, you'll want to set it up with 2 hard drives. 1 for Win, 1 for Linux. But VMWare itself is only 50 or so megs. Pretty lean.

DALE: Does VMWare use the DLLs like other open source emulators?

RICKENGELHARDT: What’s the average memory usage? Windows is a hog but Linux isn't, where’s the trade?

TIM LEE: Yes, but don't treat VMWare as an emulator. There's a 5-10% speed hit but that's not because it's inefficient. Usually emulators have performance hits of 30-50%.

JSZADA: How long has this been in development?

TIM LEE: You can set up how you want memory split. If you have 256 MB and you'll be using Windows more, then you can set up 64 MB for Linux. 192 MB for Win98.

Memory split
TIM LEE: Virtual Machines have been around since the 1960s. IBM was the first to use the virtual machine concept. They used them on their mainframes to allow multiple users to use the same processors.

DALE: Can VM use virtual memory?

PSCHUVIE: What about the NT hardware compatibility issues? Are they eliminated because of virtual construction?

RICKENGELHARDT: What about 3D cards also?

TIM LEE: Yes, VM can use virtual memory. No, the NT hardware issues are still there. 3D cards are not yet supported fully. It's in the works, though.

DALE: Like my Linux box has 256 MB. how much could I set for VM?

TIM LEE: The difficulty is that in order to use a virtual machine on a computer, drivers have to be rewritten for the VM. Then those drivers have to be made compatible with 3D graphics cards, etc.

RICKENGELHARDT: Is there any support for RAS capability? I’ve got a lot of users dialing into apps.

DALE: I guess I should say swap -;)

TIM LEE: On a 256 MB set up, we'd recommend 128 MB each. Yes RAS is supported.
Our Guild Meetings feature top-flight professionals leading discussions on interesting and valuable IT issues. You can find a schedule of Guild Meetings in your weekly TechProGuild Notes TechMail, or on the Guild Meeting calendar.
PSCHUVIE: Since you represent a hardware vendor, what might be a typical configuration for a box to hold Linux, NT and Win98?

TIM LEE: You can set any amount you want for virtual memory.

PSCHUVIE: Also what is the flavor du jour for Linux?

TIM LEE: Our Pogo Altura is the best example: AMD 600mhz, 128 MB micron RAM, 20 Gb HD, CD-ROM, Ethernet card, sound card, Matrox G400.

RICKENGELHARDT: Do you have to have both Linux and win drivers for each device?

TIM LEE: Red Hat Linux is our preferred standard. But VMWare will work on all the distributions. Yes, each device will have its own drivers. Everything is supported.

PSCHUVIE: How fast is the development cycle with VM to ensure that it stays up-to-date?

RICKENGELHARDT: The hardware requirements seem pretty reasonable for any PC, not just for a dev environment.

DALE: Windows 2000 is out, will it work for that?

TIM LEE: The development cycle is up-to-date. Even the open source project (FreeVMWare) will have support for the latest processors and devices. Yes, you can run Linux inside Win2000 or Win2000 inside Linux. One great thing about virtual machines is the isolation.

PSCHUVIE: Please expand on that if you will.

To give you an example
TIM LEE: For example, let's say you're running Windows NT and you're in a company and you have an IT department that says you should not install anything like games or any personal software on your company machine. Well, that's hard for a lot of people. You have this PC; you'd like to be able to do some things on it. Well, one of the compromises that the IT department can do is actually install VMWare and another copy of the same operating system and say here's this other virtual machine running maybe Windows NT. You can install your software on that and it won't mess up the company one. So you have a company Windows and a personal Windows.

PSCHUVIE: Are there any licensing issues then?

RICKENGELHARDT: Is there any kind of error trapping or recording available that would be the real advantage over a second PC for testing, etc.?

TIM LEE: No, Microsoft sells you 1 license for that computer. You can set up a million virtual machines but it's still on that one computer.

DALE: It once was one machine, one OS.

TIM LEE: Yes there are those mechanisms. They're called fail-safe mechanisms. Anytime something goes wrong, you can return to any point in time during the process (i.e., during installation, after installation, before installation, after executing the program, right before the crash, etc.).

RICKENGELHARDT: I already have trouble with "non standard" apps that have a legitimate business use, how could I sell this to my department IT group?

DALE: How does VM handle Windows crashes?

Crash and burn
TIM LEE: Rick, what do you mean by "non standard"?

RICKENGELHARDT: They're apps that only our business unit uses, which ultimately catch all blame for any problems because no one else uses it. It’s a terminal emulator.

STORMY: dale -> Windows crashes (if your host is Linux) are solved by restarting the "app" that is Windows.

TIM LEE: If your window crashes, it'll still crash the virtual machine. However, it won't crash your Linux machine (the host). You simply turn on the virtual machine again and you're back in business. Or if you had fail-safe set up, you'd be able to get back to where you were before the crash. You won't get your documents or work back, but you will be able to return to the location (such as which programs were running, etc.), which could be useful. Something’s better than nothing, right?

STORMY: That is, Windows crashes. You don't need to reboot. You just restart Windows. Linux remains running.

DALE: Thanks Stormy, was just wondering?

STORMY: No problem. Looks like Tim beat me to it though.

DALE: One of the other things that we use is Citrix to terminal server using 128 encryption. Will using a Windows session within a Windows session cause any problems?

TIM LEE: Rick - By standardizing Linux as the company-wide platform, most companies can save money in the long run in terms of maintenance costs, upgrade costs, and support costs. So, if people still need Windows in 10 years, VM allows them to continue to use that. By using Linux, it also eliminates the need to upgrade to Windows2000 because Linux is just as good as W2K. Dale -- nope.

What about IP addresses?
STORMY: Tim -> I would say better in many regards. ;)

WELL: Anyone know about IP address?

TIM LEE: By the way, for those of you who wonder how Linux can make maintenance easier w/VM, if Linux is your host OS, well, your network administrator can easily modify your HD (for good things such as upgrades, etc.) because he can just telnet into your machine, access the Windows-mounted drive from Linux, and do his thing.

RICKENGELHARDT: In your example you mentioned 2 machines, a company Win NT machine and a VM Win NT machine. How’s an IT department going to react to this, 2 installs of NT, not enough time?

MODERATOR: And remember, tonight's chattiest member will walk away with an ASUS K7M motherboard compliments of Tim!

STORMY: Rick -> I would think that a well-organized IT department would use a disk-cloning app of some sort. And so the installs should only be once, at least the major part anyway.

TIM LEE: Well, Rick, it would save time in the long run. 1 NT install is for the company's software. It's on the network and updated daily. Then the VM runs another copy of NT but this is only for personal stuff. So, people load their Quake3 games onto this partition and do their usual surfing here. The two are separate but equal. However, the work NT partition is never contaminated by extraneous stuff.

PSCHUVIE: How "hot" are corporations to introduce the virtual element to the broad user base. I can see dev and tech but wide spread use?

Virtual fear
TIM LEE: A lot of companies are scared of the word "virtual" mainly because anything "virtual" means it's slow, buggy and crappy. (Thanks to the effects of virtual memory, which is, slow, buggy and crappy.)

DALE: What I see is the need of a solid base for IT to support the user base.

RICKENGELHARDT: I agree with pschuvie, I see the potential but how do you sell it? I have a pretty open management staff but this would be a toughie.

TIM LEE: However, once people see up close and personal what a virtual machine can do for them, they see the great potential.

STORMY: Rick -> do you have a staff member who's constantly crashing?? We do, and it's -real- easy to sell anything that might keep him stable. ;)

TIM LEE: Well, let's say Mary Jane is using Windows98 and needs it for everything she's doing.

RICKENGELHARDT: Yes, Dr. Watson and myself are good buddies lately.

PSCHUVIE: Well, since virus has been the hot topic of the week/month where would the VM scenario help there?

TIM LEE: Oops, I meant WinNT. If she's running NT, then she can also run Linux as a separate application. As time goes by and the company migrates to Linux, she'll have the infrastructure in place and won't need a new system. Viruses are great applications for VMs. You can set up a virtual machine to "test" out virus scenarios and never lose your work. With a VM you can set up a zillion different configurations and multiple OSs to test that virus on.

STORMY: ESP if your host is a Linux box. Most viruses are not made for the *nix platform.

TIM LEE: It would save money, time.

PSCHUVIE: So the track to introduction is a combination of Linux evangelism and preconversion infrastructure building.

TIM LEE: Exactly Storm. Rick, that would be the best way to sell Linux/VM to your staff. Ya, the theme is "Win with Linux.” You can kick butt with Linux, but you also get Windows with Linux.

DALE: Well that would be fine for small shops, but what about the larger companies that have a domain?

TIM LEE: Have any of you seen our TV commercials running this month?

STORMY: *grins! * Stability is still a tough sell, when you're up against "market share" though.

TIM LEE: One of the slogans in them is "Breaking Windows with Linux" which is exactly what this combination can do.

PSCHUVIE: Tim, nope. Not here in San Diego. Where are they placed?

TIM LEE: They're nationwide on the WB channel.

RICKENGELHARDT: I think it would kick butt as a training environment for users. I always tell my users to go nuts, and that I can always reimage their PC but I wouldn’t have to, it sounds like I could just go back to before the error or app, right?

PSCHUVIE: Gee I thought all execs watched CNN or MSNBC. WB?

STORMY: I interviewed with a company today, much larger than the one I work for right now, and they're using Linux boxes, and NT. They would be perfect candidates. I see VMWare as a great opportunity to test the OS and see if it's functional for the company's use, without having to make that huge commitment right away, too.

Is NDS available?
DALE: Will there be an NDS available?

TIM LEE: Dale, a large company having its own domain for its network wouldn't have any more work to do than a smaller company. Rick, yes. Failsafe mechanism.

STORMY: Not here in Canada. ;)

RICKENGELHARDT: How does the VM handle DOS apps? Yes I've still got a few around.

TIM LEE: It runs them just fine. You get to do everything DOS-related as if it was a regular stand-alone machine.

PSCHUVIE: While we have been discussing the upsides and potentials, what are the known "issues" or where it falls down?

DALE: Rite now I use Linux to monitor my network and do administrative functions. How does VM work with SMS and other NT admin functions?

STORMY: Are they ever going to make a version for Win98?? *g* A friend wants to try it w/Linux as a guest, but won't migrate to NT.

DALE: What I mean is most of the admin functions are local, but would like to use across the domain.

TIM LEE: The disadvantage is speed and limited use of specialized hardware. There's bound to be hits in performance during CPU-intensive calculations. And also special hardware such as CAD hardware, don't work -- yet.

RICKENGELHARDT: Yes what about scripting in Windows such as Win NTRK or PERL?

What about scripting
TIM LEE: VM has interfaces to use SMS and others. I don't believe they ever will. Linux is a great OS and NT is a somewhat stable OS. I think they're trying to stay on track with somewhat stable OSs. Win98 would throw a big monkey wrench into the equation.

STORMY: The way I understand it (where Linux is host and NT guest), NT makes a request for the use of a piece of hardware, etc., and Linux will intercept that, interpret it, and then allocate the use of it. Is this right? And why doesn't NT object?? Since it objects when a program tries to access the hardware directly.

RICKENGELHARDT: How does this help me get familiar with Linux, just the comfort with my Win apps still there?

PSCHUVIE: Who are the "names" that see and agree with the VM, not your companies, but other Big names?

TIM LEE: Stormy-- because Linux is transparent to NT when using VM. NT doesn't even know it exists. It's fooled into thinking it's accessing the hardware directly.

STORMY: *g* I LIKE stuff that fools MS. ;)

RICKENGELHARDT: Does this still use NTFS?

TIM LEE: Well, Rick, if you use Win all the time, you can use Linux from Windows. It'll just be treated like an application like Word or Notepad. You use it when you want, and when it crashes, you delete it. You can still use NTFS in VM.

STORMY: What’s the benefit of using Win as a host and Linux as a guest, over using something like "LinuxforWin" like the app that Mandrake ships?

Caution: Roadblock ahead
RICKENGELHARDT: What other "roadblocks" are there? Sounds too good.

DALE: How about long term?

PSCHUVIE: Are there any white papers available at buypogo.com?

TIM LEE: Well, LinuxforWin just lets you install Linux onto a Win partition. Doesn't let you use it at the same time.

RICKENGELHARDT: Is there any other info on your site, i.e. success stories, etc.?

DALE: LinuxforWin would not be multitasking.

TIM LEE: Hey all, send me your questions if you still have any. You all really bombarded me with them and it's too bad I don't have 10 pairs of eyes and hands. :)

STORMY: OK. I've never used the L4W; I just wondered what the fuss was all about. ;)

TIM LEE: My e-mail address is tim@buypogo.com if you all want to send me fan mail via e-mail.

SOUND123: What is the future of your relationship with VMWare? And are you going public any time soon because the ticker symbol POGO is still available and I want to Buy buy buy!

MODERATOR: Thanks, Tim! That's really nice of you to provide your e-mail add for everyone!

Thanks Everybody
TIM LEE: Rick, not yet. We are working on a new site, which will have more testimonials.

MODERATOR: Okay everyone, got to call it an evening! Ready for tonight's big winner of the ASUS K7M motherboard?

RICKENGELHARDT: Hopefully I'll have a test machine up and be able to contribute soon.

DALE: Yup.

PSCHUVIE: Always ready for freebies.

MODERATOR: Big congrats go out to Dale, winner of the ASUS K7M motherboard, generously donated by tonight's speaker, Tim Lee, CEO of BuyPogo.com!

MODERATOR: But wait. There's more!

TIM LEE: Sound - IPO or bust. Wait for it in about a year and a half.

STORMY: Congrats Dale!!!

MODERATOR: pschuvie and rickengelhardt you've asked some great questions tonight also, so I'd like to award each of you a copy of O'Reilly's "The UNIX CD Bookshelf version 2.0" which also covers Linux!

MODERATOR: A big thanks to tonight's speaker, Tim Lee, CEO of BuyPogo.com!

MODERATOR: Thanks to everyone for joining us tonight! Great questions! Be sure to join us on Thursday, same time, same place, and Jeff Davis will discuss "Gearing up support to introduce new technology."

 
Our Guild Meetings feature top-flight professionals leading discussions on interesting and valuable IT issues. You can find a schedule of Guild Meetings in your weekly TechProGuild Notes TechMail, or on the Guild Meeting calendar.
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