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Đây là bài so sánh gần đây về VMware 5 và Virtual PC 2004 ...


Virtual PC 2004 vs. VMWare Workstation 5

July 11, 2005
By Jeanne Paschang
( http://www.adminprep.com/articles/default.asp?action=show&articleid=81 )

Test, test, test. How often do we hear this mantra? As system administrators and engineers, we probably hear it all the time. Below are just a few of the situations you most commonly encounter regarding testing.

• “Before you install this service pack, be sure to test it.”
• “Before you restore your SQL server, test the process so you know what to expect.”
• “Before you do an in-place upgrade of your Exchange server from Exchange 2000 to Exchange 2003, make sure you test it first.”

It is always good advice to test programs and procedures before implementing them. It is also a good practice to back up any systems undergoing a significant change. But what is the best way to do all that recommended testing? Obviously, the best way to perform testing is to install a test lab that is as close as possible to the real environment.

Why test and who has time?
I worked as a full-time network administrator over the last fifteen years for several different companies. I was one of those paranoid system administrators as many of us are. Downtime to the company meant lost revenue. To me, downtime meant angry users, lost time and/or a lost job! As a result, service packs, new product installations and upgrades made me nervous. After all, these companies relied heavily on their information systems. A bad patch could mean disaster. Some people dream of new houses, cars or boats. I often dreamt of a test lab. To that end, I presented several business cases for building a test lab. The reaction was always the same: “you want us to dedicate equipment to sit around and do nothing most of the time?” Even when I presented how many dollars could be lost in terms of productivity as the result of just a single bad software or procedure, they just did not seem to get it. One of the companies I worked for even wanted to get into the business of installing networks for small businesses, yet they resisted the idea of a test lab.

Today, as a technology instructor and consultant, I usually ask my corporate students if they have a test lab environment. The response I often get is peals of laughter. Many of them respond as follows. “Of course we have a test lab. We call it our production environment!” If they do have a lab, it consists of whatever junk machines they could piece together. I would say only about one person in eight ever raises their hand and says they have a dedicated test lab. I can understand the resistance five or ten years ago when an extra PC was a big dollar item. Additional space is often the other consideration, particularly in areas where real estate is at a premium. Time constraints are the other problem. A test lab requires regular care and feeding in terms of loading and re-loading operating systems and applications. Even today, the test lab appears to be a poor relation to the rest of the IT world.

Virtual Machines to the Rescue
But no more! Now we have some excellent products at our disposal to test whatever we need to with far more ease than in the past. Many administrators discovered the advantages of virtual machine products many years ago. Yet, I am surprised at how many administrators I encounter who are not aware of the capability of these tools. If you are one of the persons in that group, this article will open your eyes to some of the possibilities these products can bring to your networking environment. One of the most important things you can gain from these products is more stable and versatile information systems.

First, let us investigate how these products work. Virtual machine products such as VMWare Workstation 5 and Microsoft Virtual PC 2004 base their success on a common concept. The concept is as follows.

1. Install an operating system such as Windows XP on a physical machine (the host machine).
2. Install the virtual machine application such as VMWare or Virtual PC.
3. Create virtual machines (the guest operating systems) and install the operating system(s) of choice in each virtual machine.
4. You can run several virtual machines at once depending on the hardware.

Why have these programs become so popular? Let me count the ways.

First, consider the space and hardware costs mentioned above. Why fill a room with several physical machines for testing purposes when a single machine can support four or five virtual machines running on top of the host machine operating system? All of this computing power can reside in a spare corner of a cubicle. The virtual machines are portable and are far easier to build and work with than a traditional test lab.

Second, consider the application developers. I have worked with enough developers in my career to know that they usually “blow up” their workstation about once a week or so. That is just the nature of their work. They write code and in the process, the workstation is often a casualty. Before the virtual machine products, it used to be a pain getting them back up and running. You could get them a new image, but it still had to be loaded and it was difficult for them to get back where they left off before it blew up. This process amounted to lost time and effort on both sides.

More Reasons
Third, as a Microsoft Certified Trainer, I use the Microsoft Virtual PC 2004 for most of the classes I teach today. About a year and a half ago, Microsoft began using the Virtual PC product in many of its classes. This change makes it easier to setup a classroom. From an instructor viewpoint, it is easier to recover if a student makes a mistake during a lab. It is easier to provide the student with a new virtual machine instead of reloading an image. In addition, in a traditional class format, many of the labs required multiple machines with one student per machine. This setup often meant students had to work in groups. One student would do the steps in one part of the lab while others watched or waited. With the virtual machines, each student can perform all the steps of the lab independently of others.

Another advantage in the training arena is for situations where the setup requires a triple boot using Windows 98, Windows 2000 and Windows XP. Many of the A+ and Network+ classes require this configuration. A triple boot is difficult to set up and keep stable during the duration of the class. Using virtual machines, the students can run all three operating systems seamlessly on a single workstation.

Fourth, many companies are using the virtual machines for program compatibility issues. For example, a mission-critical application may only run on Windows 98. Often, this situation limits or stalls an upgrade to Windows XP. In fact, this was one of the key reasons Microsoft acquired the Connectix Virtual PC product back in 2003. (Microsoft revamped the product and reintroduced it as Virtual PC 2004). They knew many companies were not upgrading to Windows XP due to compatibility issues with legacy programs. One company I consult for actually had two workstations at each person’s desk with switchboxes so they could continue to use the old application on Windows98 and still take advantage of other programs that required XP. With a virtual machine product, they were able to remove the Windows 98 machine and the hassle of the switchbox. This change also made the users happy to get more space under their desks.

Fifth, assume you are a network administrator supporting one of these applications that runs fine on Windows 2000, but you are not sure how it behaves with Windows XP. You contact the vendor to find out about compatibility. The vendor’s response goes something like this. “Well, we haven’t run it on XP, but it should work. Oh, and by the way, when you test it, could you let us know how it goes and if you find any problems?” The virtual machine allows you to test interaction between server and workstation client so you find problems before they happen. Hmm. Maybe the vendor could benefit from this technology as well!

Finally, companies are deploying virtual machines for server consolidation. For example, many companies have four or five servers, each performing a specialized task. One server may do backups, another one monitoring and yet another one is file and print. By using one of the virtual server products such as Microsoft Virtual Server 2005 or the VMWare GSX and ESX Server, many of these roles can consolidate as virtual servers on a single piece of hardware. This use is beyond the scope of this article. Our concentration here will be on comparing the virtual pc product offerings, specifically Microsoft Virtual PC 2004 and the recently released VMWare Workstation 5.

Let’s get to it. Here are features about the two products.

On the surface, it looks as if VMWare Workstation 5 is the clear winner. However, stay tuned for the next segment in this two-part article: VMWare 2005 vs. Virtual PC 2004 – A Fight to the Finish! In the next article, we will explore how well each of these products goes head-to-head in delivering performance, features and functionality for their assigned tasks. In addition, we will discuss some optimization techniques to help you get the best performance out of each product.



Virtual PC 2004 vs. VMWare Workstation 5 (Part II)

July 27, 2005
By Jeanne Paschang
( http://www.adminprep.com/articles/default.asp?action=show&articleid=85 )

he Great Race: VMWare Workstation 5 vs. Virtual PC 2004
Now, the match race you have all been waiting for! Here is part II of the Virtual Machine product match-up. As mentioned in Part I of this article, both products are enjoying immense popularity. Which one is right for you? You make the decision!

Step 1 – Product Procurement
Before you can have a race, you have to procure the horses to run the race. In this case, the vendors make it easy on us to purchase their product. You can purchase VMWare directly from the website at www.vmware.com in electronic format, provided you have a valid email address and credit card. (There’s always a catch, isn’t there?).Once you provide the information, the company will email you your registration code. From there, you download the binaries for the product and perform the installation. At one point during the installation, the program will prompt you for the registration code. A simple cut and paste from the email you received is all you need to get started from here.

You can obtain Virtual PC from a variety of web resellers for a variety of prices. Each vendor will differ in delivery methods. For this test case, Virtual PC installed directly from the product CD. VMWare installed from the process mentioned above.

Step 2 – Assessing the Capabilities
Before horses can participate in a race, they receive a handicap. The handicap helps keep the race on an even keel. In this case, the handicap is assessing which guest operating systems are supported. Part One of this article mentions the operating system choices are, but here is a more detailed look at the screen shots of supported operating systems for each product.


Virtual PC

tep 3 - Product Installation
To keep the race even, both products install on the following hardware running Windows XP SP2. The documentation for both products refers to this base machine as the “Host PC”.

Host PC Equipment
• Compaq Evo Model 510
• Single 1.8 gig Hz processor
• 2 gig RAM
• 40 gig 5400 rpm speed internal IDE hard drives
• Both drives are defragged before beginning tests

The Virtual Machine software used is as follows. Each product runs on its own Host PC.
• VMWorkstation 5, build 13124
• Virtual PC 2004 with Service Pack 1

Virtual PC 2004 installed quickly and without incident via a wizard. There are not too many options during the installation other than location of program files. The program defaults to C:\Program Files\Microsoft Virtual PC, but you can change the installation path if desired. After the installation, be sure to install Service Pack 1 for the product to take advantage of performance enhancements and additional fixes. Service pack 1 is available for download from Microsoft’s web site.

VMWare Workstation 5 also installed quickly and without incident via a wizard. This installation program had a few more bells and whistles to the initial installation. For example, at the beginning of the process, it prompts the user if they want to install shortcuts on the desktop and quick launch bar. This feature represents basic functionality and is user friendly. Virtual PC requires the user to take the additional steps to make this happen. This is not necessarily a bad thing, as most technical users do not like to clutter the desktop or launch pad with additional shortcuts. It is all a matter of preference. VMWare presents a program tip once the application launches. Again, this is a nice feature for users new to the Virtual Machine world.

Step 4 – Saddle up for the race
There is always preparation work to do before a horse race. The horses need saddles and equipment, the jockeys weigh in and other little details have to happen. Likewise, the virtual machine environments require similar preparation. Here are some of the planning details to consider before installing the operating systems.

First, like any standard installation, you need to determine how much drive space you want to allow for the virtual machines. Both products refer to these machines as “Guest PCs”. In this case, the installation is a default installation of Windows XP with few applications, so excessive drive space is not necessary. For the test environment, the following table illustrates the Guest PC environment for the installation. Again, both platforms install with identical specifications and setups as outlined below.

• Windows XP SP1 operating system installed from CD
• Drive space allocation 6 GB
• RAM allocation 512 MB

The RAM allocation is a very important point to consider before the installation. Because Windows XP is a Microsoft product which requires activation, changes to the virtual machine environment after the Guest PC after installation can trigger reactivation. VMWare displays a couple of warnings to this effect during the Guest OS installation, but Virtual PC does not at this point. See the VMWare warning below.

Each product takes a slightly different approach to creating new virtual disks. The following excerpt is a quote from the Virtual PC 2004 help files defining the virtual disk concept.

“Virtual hard disks and virtual floppy disks provide functionality that is similar to their physical disk equivalents. Virtual disks support both writing data and reading data. A virtual disk is stored on the physical computer as a single file. Virtual hard disks and virtual floppy disks are created using the Virtual Disk Wizard. A virtual hard disk is a single file on the physical computer that stores all the data used by the operating system installed on the virtual machine. Virtual hard disks have a .vhd extension. From within the virtual machine, the virtual hard disk appears to be the same as a physical hard disk. The virtual machine uses the virtual hard disk the same way that a physical computer uses a physical hard disk. There are several different types of virtual hard disks available.”

The idea is to define the parameters for this file before installing the Guest OS. In Virtual PC, by default, you will get a 16 GB virtual hard disk. To specify an 8 GB virtual disk as desired for this test, you must create the disk in the Virtual Disk Wizard. The options for the Virtual PC disk are as shown in the diagram below. Each option is well explained on this screen.

For VMWare, the virtual disk creation happens differently. When the user selects to install a Guest operating system, the system prompts for the virtual disk size and options. See the diagram below.

The Race is On
In the first meeting, a default installation of Windows XP SP1 is the test track each product will try to conquer. Side by side, the two machines raced to see which contender could install this popular operating system first. As you can see from the chart below, both champions bolt from the gate with a strong start. Neck in neck toward the first turn, they complete the quick NTFS format at the same time. However, racing toward the second turn, VMWare pulls a slight lead, finishing the file copy after format a full two minutes ahead of Virtual PC. By the time they round the third turn, VMWare starts to assert its lead. Heading into the home stretch toward the finish line, VMWare pulls ahead with a comfortable lead, finishing the XP installation in 18 minutes as opposed to 41 minutes for Virtual PC.

Step 6 - Who gets the roses?
However, what is speed you say? Most of us are in the habit of multi-tasking, especially when performing installs. The bottom line is – they both get the job done, but if you are a Type A personality, VMWare might be your preference.

Once the guest operating systems installs, what else needs is there to do? There is additional work on both platforms. For example, once the operating system installs and starts, both products prompt you for additional steps to perform. The steps below help the operating systems attain maximum performance and user experience.

VMWare offers VMWare Tools. This is an additional installation to the guest operating system. The tools enhance the screen resolution, mouse integration and provide other rich features. Most importantly, the installation of the tools allows free movement of the mouse cursor between the Host PC and the Guest OS. Without the tools, the user must select CTRL-ALT to “release” the mouse from the Guest OS. The tools are available from the main VMWare menu. For this process, you must log into the Guest PC as an administrative account. These tools are available from the VMWare menu.

Virtual PC offers VPC additions. The VPC additons perform much of the functionality of the equivalent VMWare Tools. These additions are available from the Virtual PC menu.

Step 7 – Head to the Forums!
So who is the winner in this round? You be the judge. As one reader in the forums already noted, price is a big factor in many of these decisions. Both a Lexus and Toyota will get you from point A to point B, but you pay for the extra features and the name on the Lexus. In my opinion, both of these products perform well, but it does depend on what your environment requires and of course, the budget. Both products are good quality and perform as expected (no Ford escorts in this bunch!).