Monday, July 31, 2006

Virtual PC - Which one is best?

VMware: Build a multi OS haven

At times, you may desperately need some other operating system to perform your tasks as you find it very difficult to work exclusively with the only operating system installed on your PC. In such situations, either you opt for multiple boot option in your PC having different OS installed in different partitions, or go to separate, independent, physical machines. Sometimes, multiple boot option may not be possible due to file system conflicts etc., for example, you cannot boot in to Windows 3.1 OS in a computer having FAT 32 or NTFS file system. You need to create a separate, exclusive FAT16 partition for this OS. Similarly, the competing Linux is real hot today and more and more Windows users are joining Linux bandwagon just to experience its open source flavor despite some difficulty in configuring this OS. Situation is that, presently, what Windows offers you, may not be available in Linux and vice-versa, so you need some tools or a piece of software that may address your need to be able to work in Different OS in same machine in same OS without having to reboot.

There are numbers of software available today that may help you in this field. You may have listened about famous DOS Emulator that provides you facility to run DOS and its applications in UNIX platform. The need for tools that make your existing OS cross platform compatible has really increased especially after evolving of LINUX as a powerful Network and Desktop Operating System. Operating System emulators or Virtual machines are especially written software that helps you run application and OS of other platform (Guest OS) on your existing platform (Host OS). There are some tools for MAC and UNIX world for running applications and OS of different platforms and so are for Windows and Linux. Let us see what are there in the box for today’s these two top most popular OS, i.e. Windows and Linux.

Following are some software distributions that can be used for running applications and OS on cross platform:

  1. WinLinux 2000: This is a Linux OS distribution designed to run as a Windows application in existing Windows partition. It installs in Windows file system after creating a large file to install Linux and then creates an icon in desktop or in program group as shortcut to boot in to Linux. Double clicking it launches the Linux and you can work in Linux without rebooting. But you cannot work simultaneously in Windows.
  2. Ne Traverse Win4Lin: This application, available for Linux platform is a Windows Emulator. You can install and run Windows OS and Windows applications in Linux platform with the help of this software.
  3. Wine: This Linux application can run Windows applications in Linux environment. Often it is mistaken for as Windows Emulator, which it is not. In fact, it creates a Windows compatibility layer to run Windows applications in Linux environment without running Windows. However, there is a precondition that the Windows applications should be properly installed in a separate partition that may be either in local or remote disk, in Windows OS environment and is configured accessible to Linux. Wine provides a virtual Windows environment, in which Windows applications [and not Windows OS] run. A detailed guideline to how to use Wine has already been published in this magazine previously.
  4. Win to Net: This software allows your computer having java enabled web browser such as Linux and Free BSD to access and run Windows applications.
  5. VMware: This promising software can create and run any number of virtual computers with different OS within a single, physical computer without partitioning or rebooting. Thus VMware can turn your single PC in to a number of virtual PCs running simultaneously. VMware can run arbitrary OS from DOS to any version of Windows to Linux and Free BSD within the single PC and in single partition. VMware can support networking, sound and multimedia. VMware is currently available in Windows NT/ 2000 and Linux platform.

Among above listed software, VMware has true potential with cross platform compatibility. It has different versions that can be installed either in Windows NT/2000 or in Linux and once installed and configured properly, you can run any number of OS simultaneously that your PC’s processing power and RAM can permit you. In fact, you can build a multi OS haven with this application. The application requires some expertise to run; however these can be quickly learned. If you have some knowledge of Networking, file system and partitioning etc., then you will not find any difficulty in running this application. Let us see how a multi OS haven can be build with VMware.

What VMware can deliver?

Besides fulfilling your need to have more than one OS in your PC in which you can work without having to repartition or reboot, VMware can deliver productivity to you if you deal in variety of software production and testing. For example, say, you have developed a piece of software for Windows platform and want to test it in all versions of Windows i.e. from Windows 3.1 to WindowsXP. Now you need to have to multi boot to at least 5 partitions or boot in to 5 separate PCs having installed different versions of Windows to test your product. This way, you loose your precious time and resources for each OS. Further, if you plan to use single PC with multiple partitions, then you may need third party boot manager to boot in to every version of installed Windows individually. The job becomes more tedious when you involve in more and more areas. Software giant like Symentec, the presenter of famous Norton Utilities, deals with variety of software products ranging from Antivirus tools to Internet Contents to Mobile Technologies and other Utilities that needs hundreds of numbers of test machines to simulate exact working environment at field for testing. With VMware software, this can be done in Virtual Machines making large scale testing and debugging more productive, easier, and cheaper. It is one of the best software for hardware and software testers. If you use VMware, rebooting will be a history and, with its equally powerful feature called “Suspend” mode [equivalent, but more advanced than Hibernate, available in some system], you never need to reboot any of your Virtual machine except in certain conditions! To add to this, you can work on practically any number of OS simultaneously [on Virtual Machines] that your computer’s hardware [mainly processing power and RAM] can support. VMware calls it as “multipleworlds” technology.

How VMware works?

VMware was initially launched for Linux workstation systems to run Windows OS. The version 2.0.4 is made available for Windows Nt / 2000 workstation also. There is a server version 1.0.0 also available for Linux platform. Installing VMware in Windows is fairly easy, but you have to learn configuring it. Like any standard Windows application, it installs with Installshield wizard and asks you a few questions that you have to answer. Whereas in Linux, it comes as RPM files and you need to install it by giving suitable command. Make sure that your XWindows in Linux is running and configured for high resolution. In evaluation version, you need to obtain a product initiation key from company’s web site that comes as a file for Linux and an executable registry file for Windows. You need to install and copy these files properly so that VMware can start functioning. Once installed, you can launch VMware application by double clicking its program icon in Windows and giving command vmware & in Linux terminal.

VMware can access and boot from your existing partitions and existing installed OS. It can also create any number of virtual disk or raw disk in your existing partition in which you can install any number of supported OS. The Virtual or Raw disk behaves like a conventional physical hard disk drive on a real computer. You can format it with any of the supported file system. The Virtual Machine has its own BIOS that you can setup during its booting time by pressing function key, F2. Existing, previously installed OS that can be boot up in Virtual Machine is limited to local Disk and local Partition. But you can create as many virtual drives on local as well as remote drives within VMware environment and can install and run any number of OS.

When VMware starts, it asks you for running configuration wizard, existing configuration or a configuration editor. Select the appropriate option you want. If you want to install new OS, then configuration wizard is recommended since it is very easy to work on. Select the directory and size where you want your Virtual Machine should be, and you are ready to boot in to new Virtual Machine. Now save your options and power on your Virtual Machine by clicking Power On button. Virtual Machine’s boot-up process initiates by checking assigned RAM [that is the part of your actual, physical RAM] and IDE drives etc. Virtual machine has its own BIOS setting which can be changed by hitting function key : F2. Newly created Virtual Disk is needed to be partitioned and formatted with the required file system that has to be installed as new, host OS. Now you are ready to setup your new OS in this new Virtual Machine. In similar steps, you can create any number of Virtual Machines.

Additional features:

Besides full networking and ftp support, including cut-paste support between all installed Host OS and Guest OS in VMware, there were some additional extremely useful features available in VMware that you can use effectively. For example, you can save the state of your Virtual Machine to disk or memory by ‘suspend’ command. Suspend to disk feature is very useful. Your entire work at present status is saved in disk and can be instantaneously accessed with a click of a button bypassing lengthy process of booting. This is similar to the feature hibernation available in some system like Windows 2000. You can shutdown your Physical machine safely after saving the state to disk, and can instantaneously access the saved state days after by launching your Virtual Machine. This way, you can use your Virtual Machines as boot once, run forever type machines. However, check if you have saved your Virtual Machine to memory. In this case, you need to shutdown your Virtual Machine prior to shut down Physical Machine, and you have to reboot your Virtual Machine in next session. It is also recommended that you do not use suspend mode on existing partition in existing, previously installed OS if you plan to use it independently, else you may encounter errors.

There is a system configuration tool available for Virtual Machines installed with OS like Windows95 and above and Linux; through which you can configure basic hardware and its drivers like Super VGA driver for graphics card etc. This tool is not available for DOS and Windows3.1.

VMware supports almost all x86 operating system from age-old Dos to young Windows 2000 and from Linux to Free BSD. You can run any of your Virtual Machine in full screen simultaneously with your other applications that are still running in background in different OS. You can share files among virtual machine, use cut past between Virtual Machines and thus can build a virtual network of different OS within your PC. It can run client server, web application server etc. between Virtual Machines on the same PC. It supports most virus scanners and they work without major problems. It has neatly organized on line Help through which you can get instructions for configuring and running VMware effectively. In fact, if you launch some function in VMware, every time, the help window containing the help instruction regarding the chosen function appears first that may be annoying to you at times.

VMware has potential to provide you additional security. You can put your secure data in Virtual Machines installed within physical Machine which becomes un-accessible until and unless that Virtual Machine is running. VMware supports Ctrl+Alt+Del key combinations, but you have to use Ctrl+Alt+Insert key combination for Guest OS. The original Ctrl+Alt+Del keys are reserved for Host OS.

The minus part:

Besides having tremendous potential, this software is still in evolving stage and hence have some shortcomings that need to be addressed. During testing on a standard system with 500Mhz processor, 128 MB RAM and Intel 810 motherboard with in built graphics and sound, Windows 2000 as host OS, the following problems though not big, were detected:

  1. VMware may cause problems with third party Boot loader in booting the existing, previously installed OS. However, during testing, it tries to finish boot process after bypassing the third party boot loader, XOSL.
  2. Multimedia support is in initial stage. You may not be able to run your multimedia applications. Presently, only Sound blaster 16-bit compatible soundcard support is available for Virtual Machines that may not work properly.
  3. Virtual Machines tend to run slow since they share system resources. Strangely, at times, movements of mouse pointer also become sluggish in Virtual Machines.
  4. During startup, Windows 2000 smells some problem in the drive where Virtual Machines are installed and tries to force check and correct them. Further, all your Virtual machines are created as a folder in the directory you assigned in Host OS. Accidentally deleting it may deprive you of that Virtual World including all its content and data.
  5. If you run your existing, previously installed OS as Virtual Machine, be careful. Your Settings may get disturbed if you suspend this Virtual Machine; and if you try to boot normally, you may find errors.
  6. All hardware are not supported in Virtual Machine. Only basic hardware are supported as of now. Configuring some hardware in Virtual machine environment is also difficult in some cases. For example, if a certain Virtual machine is using Printer port, then unless it is released by that Virtual Machine, you cannot use it in other Virtual Machine Environment as it will not be available there.
  7. Some software that access hardware that are not supported, may behave strangely in Virtual Machine environment.

Despite having these shortcomings which are likely to get addressed soon, VMware really tries hard to deliver what it promises: MultipleWorlds!.

Box item:

Want to know more about VMware or dying to create a MultipleWorlds for you? Following link may help you more.





Snapshot description:

  1. vmware01: Installation of VMware is very simple. For Windows platform, there is an executable file, which installs the application upon running it. Whereas in Linux, it comes as compressed tar file or RPM file.
  2. vmware02: VMware distribution is less than 10 MB and takes hardly a few minutes for setup in an average machine.
  3. vmware03: VMware for Windows is somewhat costly, but you can have flavor of its evaluation version for free for 30 days. VMware also comes with SUSE and TurboLinux distribution.
  4. vmware04: Evaluation version of VMware needs a product initiation key that is a Windows registry entry for Windows NT / 2000 and a file in Linux.
  5. vmware05: A successful registration entry completed for VMware evaluation version, without which it may not run.
  6. vmware06: VMware startup screen. You have to select one of the three options available to start VMware.
  7. vmware07: You can use Virtual disk to install new OS or use existing previously installed OS from existing Disk partition.
  8. vmware08: VMware’s Virtual Machine has its own BIOS that can be configured by invoking F2 key (and not DEL key as in physical machine)
  9. vmware09: Newly created virtual machine needs to be formatted for the file system of OS that is to be installed.
  10. vmware10: Virtual machine has similar boot up processes that a physical machine has. When a blank floppy was put as boot media, it displays invalid system disk error.
  11. vmware11: In a Virtual Machine under Windows 2000 environment, Windows 98 startup disk is in booting process.
  12. vmware13: You have to run Fdisk utility for the newly created virtual machine for installing DOS / Windows OS, so that your Virtual Disk can be detected.
  13. vmware14: Windows 3.1 setup is in progress in a Virtual machine within Windows 2000 environment.
  14. vmware15: It takes less than 2 minutes in installing Windows 3.1 in virtual machine within Windows 2000 environment.
  15. vmware16: You can use all versions of DOS and up to Windows 2000, Linux and FreeBSD OS as your Virtual machine.
  16. vmware17: Existing, previously installed Windows 98 is booting inside Windows 2000 OS environment.
  17. vmware18: In Virtual Machines, all the OS works perfectly well. Here, Windows 98 on its first boot in Virtual Machine is detecting Virtual Machine’s Plug and Play BIOS and is installing software for it.
  18. vmware19: In Virtual Machine environment, the system tends to go slow. A typical Windows98 installation takes more booting time in Virtual Machine than in Physical machine.
  19. vmware20: Basic applications such as Word and Excel work perfectly well in Virtual Machine.
  20. vmware21: RedHat Linux is running in Virtual Machine as Guest OS in Windows 2000 Host OS.
  21. vmware22: In a Windows 2000 Guest OS, two Host OS are running. One is Windows 98, which is already running, and the other is Linux, which is booting up.
  22. vmware23: Non-supported old OS like Windows 3.1 is booting as Guest OS in Windows 2000 Host OS.
  23. vmware24: Linux OS installation is in progress as a Guest OS in Windows 2000 Host OS, and is easier in comparison to installing Windows OS in Virtual Machine, as disk partition and file system settings are handled automatically in Linux installation.

VMware and security issues

It is impossible to stop hackers and intruders to invade your machine if it is connected to a network. Firewalls can help you up to a limit, since hackers can replace system commands with their own versions, your running process can be altered and Operating System Kernel can be changed to their versions. The best you can do is watch and control their activities inside your computer. One of the most effective ways in controlling hackers and unauthorized intruders is by using Virtual Machines. Virtual Machines can also be used for testing hacker’s and intruder’s program files and Viruses without damaging physical machines, since Virtual machines can be made to run in isolation within physical machine and you can reset your Virtual Machine to its initial state umpteen times without any difficulty. For example, you can run Melisa type deadly virus in Virtual Machine in your own PC without any worry.

However, there is a catch. If the virus or intruder’s program file contains certain instructions called logic bomb, which are written to explode only in specific conditions, you may not be able to take a peek over it even in Virtual Machines, since it may not find the condition suitable in Virtual Machine environment. The Virtual Machine requires support in CPU, and if it is not available, then again, it is run in software emulation, which again reduces running application’s speed. Still, VMware is useful in testing most common forms of security issues such as system hacking, viruses and worms.

UPDATE : Vmware server is now available as freeware!

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