Running Multiple Operating Systems
Dual Boot - Multiple OSs - Partitioning Your Drive - File Systems
Overview
A Work-in-Progress
This page is an update to the information found in the OS/2 Resources section of this site and to make it more relevant for Windows users.
Not for Novices
Some of the information on this page will require more than a basic knowledge of the various operating systems you wish to work with, including understanding file systems, the ability to work with advanced installations and often with at least a basic understanding of the various components involved in today's computers.
Be aware of the date that many of these resources (particularly the links) were created. Some of the assumptions may no longer be valid. It is best to view as much about the knowledge you are seeking as you can find. Between these various articles you will begin to get a sense of what is right for you and for the current accuracy.
Aimed at Windows Users
The information on this page is generally aimed at Microsoft Windows users, but has information and resources for other operating systems.
If you are unsure of what is being discussed, you should consult someone with the necessary experience. If you are contemplating more than one operating system, be sure the person understands both operating systems, particularly if you have existing data or other software to protect.
About Virtual PCs
While there are options like virtual PC software such as Microsoft's Virtual PC 2007 (runs on Windows XP Professional, Windows XP Tablet PC, Windows Server 2003, Windows Vista Business, Windows Vista Enterprise, and Windows Vista Ultimate) or Parallels, sometimes such solutions are too complex or expensive in both pricing and performance requirements.
Backup Your Data!
You should backup your data in case something does go wrong during any of the procedures on this page. It is strongly recommended that you make routine backups because hardware failures, viruses and other disasters happen—not to mention human error.
Multi-OSs or Dual Boot
Several terms are used (sometimes incorrectly) to describe the option of running more than a single operating system on one computer. I'm going to use the following two terms:
- Dual boot: running more than a single version of the same operating system (i.e. Windows XP and Windows 2000)
- Muli-OS: running more than a single operating system (OS) on a computer (i.e. Windows XP and Linux).
Why Multiple OSs?
There are several reasons for running either a dual-boot or multi-OS computer, including:
- You want to run a "gaming machine" as well as a "business machine" on the same computer.
- Web designers want to view their work on various operating systems and their native web browsers.
- A piece of legacy hardware, such as a scanner, works on Windows 98, but not in Windows XP.
- IT staff need to be able to work with older as well as new versions of Windows.
- You want to experiment with an operating system like Linux, but need to be able to use Windows as your main operating system.
Potential Compatibility Issues
The fact that you can share the hardware means a savings of the cost of the hardware as well as the amount of space you can dedicate in your working environment for multiple computers.
However, there are potentially some compatibility issues, particularly when running multiple OSs. You'll want to check for the availability of drivers for the operating systems that you want to run for your particular hardware. This is particularly important for legacy operating systems (those no longer supported with newer hardware) and with newer operating systems (which may only offer beta drivers or perhaps none at all for your hardware).
If you need to share data between the various operating systems, it gets more complex because you're forced to use the lowest common denominator in terms of what file systems are used—at least on the data partition or drive.
Dual Boot
Dual Booting Windows XP
A feature of Windows XP has been the ability for it to allow for an existing legacy Windows system for coexist with it, particularly if the existing version of Windows is already installed when you install Windows XP.
You should not mix the contents of the two versions of Windows in the same partition. Use separate partitions (I'd recommend separate hard drives, if possible) so that the resources are not intermingled. Windows 9x (95, 98, 98SE—although only Windows 98SE is practical) has a very different way of handling many files than XP does, including "user" folders such as My Documents.
Sharing With Different Windows Versions
Windows 2000 and XP should be run on the NTFS file system, but if you want to be able to see the information on these partitions from Windows 9x you'll need to use Fat32. There are great advantages to NTFS, including the ability to handle much larger drives, automatic compression and improved file features, such as private folders. Unless you need to see and dynamically alter the information on the Windows XP partition, I'd use NTFS.
If you choose NTFS, Windows 9x will be unable to "see" the Windows XP drive. You'll have to share documents with one of several methods, including:
- A common drive or partition formatted with the FAT32 file system. This can be either an internal drive or an external USB drive.
- A USB thumb-drive (you'll need to install drivers for Windows 98SE). This works if you seldom share information.
Obviously, this has limitations if you are going to be continually sharing dynamic information and it will be impossible to share programs.
Windows 9x Least Flexible
Windows 9x demands the C: primary partitions) and is a predatory operating system that will try to write data into any drive or partition that it can read (FAT16 in particular). It will offer to format anything it cannot read (such as NTFS or HPFS) if it can "see" it.
Install Programs on Both Versions of Windows
You will need to install the programs in both versions of Windows, so that the correct information is written into the Windows Registry for each operating system, even if you are sharing the program data.
Dual Booting Resources
- How to create a multiple-boot system in Windows XP
- Multibooting in Windows XP Made Easy
- To specify the default operating system for startup
- Dual Boot Windows XP Tips! from WinXpFix.com
- Multiple operating systems and file system compatibility
- Deciding Whether a Computer Will Contain More Than One Operating System
- Installing more than one operating system on your computer
- Choosing a file system: NTFS, FAT, or FAT32
The Multi-OS Environment
The Multi-OS Environment
About IBM OS/2 and ECS
There is multi-OS information more relevant to OS/2 or eCommStation users in the OS/2 Resources Section, although much of the information is more dated than what is on this page.
OS/2 and eCommStation provides a stable and work-friendly business operating system which wins over those that take the time to learn its advantages. However, the ability to play games and support for much hardware and accessories is either unavailable or not as advanced.
Hardware Options
You can use various hardware devices to enable you to boot to alternative operating systems. The advantage is that you don't have to worry about one operating system damaging the information or file systems in another operating system's partition. The disadvantage is that it is impossible to share data and/or programs because they are physically separated.
Removable Drive Bays
Since the price of hard drives has come down significantly, you can purchase a removable drive bay that can be easily swapped for your various OSs. Note that you should be sure to purchase the same brand and model of drawer if you wish to leave the hard drives in the bays and ensure that the correct drawer is purchased if you are running ATA66 or better drives.
Swapping Cables
If your need for changes is infrequent, you might consider simply swapping the cables inside your computer when you need to switch operating systems. This does require you to open the computer case and is not an option for laptops, but it only costs the price of the additional hard drive(s).
Note that newer computers continue to have power when they are shut down. Be sure to remove the power cable from the computer and ensure external devices and the monitor are turned off (a common power bar works great for this).
BIOS Changes
You might try changing the boot sequence in the BIOS to boot to a different drive or to enable/disable SATA and IDE drive options. This should only be contemplated if you understand the BIOS and can comfortably experiment with this option.
Software Options
Boot Managers
There are various boot manager program that dynamically will allow you to switch between various operating systems. These program can "see" various types of file systems and usually provide some sort of a boot menu that intervenes in the normal bootup of your computer so that you can make a choice.
- zBoot Manager.
- Power Boot is a utility that allows you to install and run multiple operating systems without the restrictions that others like Boot Manager and CtrAltDel Commander impose such as the ability to place an OEM version of software that checks for other operating systems before allowing a new installation (e.g. Windows 9x).
- One of the oldest is System Commander from V Communications. System Commander allows up to 32 Operating Systems in a DOS partition or each in their own primary or logical partition. You might wish to read the review of System Commander Deluxe by Walter F. Metcalf.
- kBootManager is intended as a supplement or replacement for the OS/2 BootManager.
Partitioning Your Hard Drive
Backup Before Partitioning
You should backup your data in case something does go wrong during any of the procedures on this page. It is strongly recommended that you make routine backups because hardware failures, viruses and other disasters happen, not to mention human error.
One or More Partitions
A single hard drive can be formatted with one or multiple partitions. The first (or Primary) partition is made active (bootable) and any other partitions are grouped into a Logical partition.
In Windows, each of these partitions are assigned a drive letter by Windows, if it can "see" the file system on that partition, and ignored if it can't. Whether or not a particular file system can be seen depends upon the version of Windows and if there are operating systems other than Windows installed.
Partition Utilities
The traditional tool for creating and deleting partitions is FDISK—a command-line utility from the days of DOS.
However, you can boot to the Windows XP installation CD on most computers, then create or delete NTFS or FAT32 partitions. If you delete or format a partition, it will erase all information on that drive.
Partition Magic
One tool that you will find useful in setting up multiple operating systems is Partition Magic (now owned by Symantec). You can create and modify partitions without destroying the data although you are advised to backup the data in case something does go wrong during the process. The newest version works only in Windows.
The display in the image above shows a FAT32 C: partition labelled WIN98 and a Logical partition that contains two FAT16 partitions (D: and E:). While this image shows an older system with FAT32 and FAT16 partitions, modern Windows systems are more likely to contain NTFS and FAT32 partitions.
Beware of Possible Gottchas
If you are running Partition Magic in Windows, it may offer to "fix" partitions on a multi-OS system. Because not all operating systems create partitions the same way, this can make destroy partitions containing other operating systems such as OS/2. If this happens, you'll not be able to recover the data on those partitions.
GParted Live
Gnome Partition Editor is a Linux solution, but Windows users can use GParted Live by booting from another device like a USB thumb drive or a CD-ROM. Because it is open source, it is free to use.
Multi-OS Resources
- General Information on Starting Multiple Operating Systems
- Multiple Operating System Setup
- Das Boot ("Getting the boot") is dated 1995 but has some good basic information about how various operating systems work and how you can get them to work together.
- Managing Multiple Operating Systems HOWTO is a useful resource for those wishing to run multiple OSs with Linux.
- Virtual Machines: An Alternative to Dual Booting.
File Systems
There are numerous file systems, many of which are specific to one or more operating systems. Because they handle information in different ways, they each have advantages and disadvantages. As file systems age, their limitations increase, much like the limitations of the operating systems they run on.
For the most part, the differences are transparent to the average user, except during installation — if choices between two or more file systems are offered.
Various PC File Systems
The more common PC file systems are shown in the table below (in order of increasing superiority):
| File System: | Description: | Used By: |
|---|---|---|
| FAT16 | File Allocation Table (16-bit) | DOS, Windows 3x, 95, OS/2, digital cameras |
| FAT32 | File Allocation Table (32-bit) | Windows 95B, 98, Me and XP |
| NTFS | New Technology File System | Windows 2000, XP and Vista |
| HPFS | High Performance File System (16-bit) | OS/2 and early NT4 |
| JFS | Journal File System | OS/2, eCS |
| Ext2/3 | Extended File System | Linux |
| WinFS | Windows Future Storage | Not used |
Other File Systems
Of course, there are many other file systems and the comparisons are interesting. Don't forget to take into account the age of the file system. Older technology is not going to have the hind sight available to newer releases.
- Microsoft's Overview of FAT, HPFS, and NTFS File Systems
- DOS FAT 12/16/32, VFAT
- File systems (FAT, FAT8, FAT16, FAT32 and NTFS)
- New Technology File System (NTFS) has interesting history, but is somewhat cluttered by ads at the top.
- NTFS compared to FAT and FAT32
- NTFS and FAT File Systems Explained
- High Performance File System
- Overview of the JFS file system.
- File systems HOWTO by Martin Hinner documents how to see other file systems (including HPFS and OS/2 LVM) from various operating systems, including NT4, DOS and Linux.
- The Linux File system.
- List of Linux File systems, Clustered File systems.
In many cases, operating systems can use multiple file systems and your choices to use one over the other might include security concerns, data reliability, speed of access, backwards compatibility with earlier systems or any number of other reasons.
Can You See Me?
Operating systems generally cannot "see" the file systems for which they were not designed (at least not without third-party utilities). For example, Windows 98SE would not be aware of an NTFS partition, but would see and be able to work with files on either FAT32 or FAT16 partitions or drives. Generally, Windows can see the file systems for the versions prior to it.
Prepare for Multi-OS Installs in Advance
One caveat: You should set up the partitions prior to installing the operating system(s) since adding or changing the file system can alter the drive lettering as it is viewed by the various operating systems. Operating systems beyond the C: partition might not be able to boot or if they boot may be unable to locate programs on other partitions.
File Systems Resources
www.russharvey.bc.ca/resources/multios.html
Updated: July 23, 2010
