Thread: How to introduce multibooting

Adding Vista to XP
One of the most common dual-boot setups is to run Windows XP and Vista alongside one another on one disk. This can be very simple to set up, but the method depends on what you're starting with.

If you're starting with a Windows XP computer and adding Vista, the process of dual booting is simple. If there's room on the disk for a new primary partition then add one, or if not make room first using a tool such as Gparted . If you're unclear about the difference between primary and logical partitions, see the box on the next page. Install Vista into the new partition and it will automatically create a boot menu with two options: 'Earlier version of Windows ' and 'Microsoft Windows Vista' .

By default the menu will wait 30 seconds and, if nothing is chosen during that time, start Vista. You can change both the time limit and the default, however. In Vista, start a command prompt with administrator privileges: press Start, type cmd, right-click the cmd.exe program shortcut that appears and choose Run as administrator. To alter the time limit to 5 seconds type:bcdedit/tillleout 5

To change the default option you need to know what each is called. Type: bcdedit/eflum and a list will appear. Look for the paragraph that lists the XP boot settings and find the identifier: this will normally be {ntldr}. Use the bcdedit command to make this the default: bcdedit/default {ntldr}

Adding XP to Vista

The only real problems with this setup appear if you install XP after Vista rather than the other way around. This is because, whereas Vista was designed to look out for an XP installation and accommodate it, XP's setup program will simply ignore Vista and set itself up as the only option. In order to recover from this you'll need a Vista installation DVD.

If you find that after installing Windows XP your copy of Vista is inaccessible, restart the PC and boot from your Vista installation disc. Choose English UK at the first screen and at the second click the 'repair your computer' link, The setup program may find the problem and offer to repair it automatically: if so, choose 'Repair and restart', If not, click Next at the list of operating systems and choose to open a command prompt. Next, type:
bootrec. exe /flXmbr bootrec.exe /flXboot
These commands will remove XP from the hard disk's Master Boot Record (MBR) and reinstate the Vista loader, When you restart the computer Vista should become available, Sometimes after doing this Windows XP will disappear from the boot options and Vista will start immediately. Ifthis happens you could boot Vista and
use the bcdedit command to reinstate a Windows XP entry in the boot menu. For a less fiddly approach, though, download the EasyBCD tool .This is a free graphical interface for bcdedit that makes the process far quicker.

Once installed, run EasyBCD, ClickAdd/Remove Entries from the menu, select the Windows tab and set the Type dropdown to 'Windows 2K1NT/XP/2K3'. Give the entry a name, then click the Add Entry button and then Save. On restarting the PC you should see a new option for WindowsXP.


Adding Windows 7

Another great reason to try dual booting your computer is to install the Windows 7 beta. Although Microsoft has now ended widespread access, the OS is still available to members of the Microsoft Developer Network or you may have already downloaded a copy.

This process is relatively simple as, unlike Windows XP, its boot management system is virtually identical to that of Windows Vista. This means the two can be easily installed alongside one another.

If you install Windows 7 on a new primary partition alongside dual booting Vista and XP, the setup ofthis menu can be adjusted using the bcdedit command from an administrator command prompt in Vista. If you use the bcdedit enum command you'll see that Windows 7 uses an identical bootloader path (\windows\system32\winload.exe) and windows directory (\windows) to Vista,just in a different partition.
Problems with the Windows 7 bootloader can be fixed in a manner almost identical to Windows Vista. If Windows 7 disappears from the boot menu after another operating system is installed, boot from its DVD, choose English UK and the Repair option and follow the instructions given for Vista above.

Removing systems

Windows 7 is currently only available as a beta, so the chances are you will want to remove it once a new version appears. To do this, boot into Vista and start the EasyBCD tool. Choose the Add/Remove option from the left menu, then select the Windows 7 entry in the list to the top right and click Delete. The operating system will vanish from the boot menu, allowing you to safely delete or reformat and re¬use its partition. Windows XP can be removed using the same method.

Linux and Grub

Installing various versions of Windows together can be handy, but using Windows and Linux on the same PC is also a popular choice, The process is a little different, though, as Linux includes its own boot management system A few are available, but the most common is the Grand Unified Bootloader, or Grub for short.

As with anything Linux-related the exact methods involved in dual booting depend on which distribution you are using, but for this article we'll use one of the most common: Ubuntu 8, 10.

Fortunately, modem Linux distributions are good at spotting other operating systems on the same disk. Install Ubuntu 8, l0 in a partition next to Vista, for example, and it will create a boot menu with four options: one for Linux, two for troubleshooting and then a fourth option that starts Windows. Install Ubuntu alongside both Windows Vista and Windows 7 and this Windows option will open a new menu allowing you to choose between them.

Changing the way that Grub works is as easy as editing a text file, although you do need administrative privileges. Start Linux, open a terminal window and type: sudogeditlboot/grub/menu.lst

You'll be prompted for your password, then the file will open. If you're using a version ofLinux that doesn't use Gnome, such as Xubuntu, you'll need to use a different text editor such as vi instead of gedit.

The menu. 1st file is quite long, but it's also simple to understand. First look for the line that begins with 'timeout' then a number - change the number to alter the time that the mertu will appear for before the default operating system is started.

Changing the default operating system is slightly more involved. Look down near the end of the file and you'll see entries for each of the start-up options: normally three for Linux followed by one for Windows. There is sometimes a 'spacer' entry between the Linux and Windows entries, too. Count from the first entry, which Linux considers to be zero, t9 the one you want to start by default - if you want Windows this will normally be three or four. Enter this number in the 'default' row further up, which will normally say 'default 0'.


Removing Linux

Grub is a powerful and versatile bootloader, and with the options stored in a single file it's generally easier to edit than the settings used by Microsoft's version. The only difficulty comes, though, if you want to remove Linux and go back to Windows. If you simply remove the Linux partition that will delete the menu. 1st file containing the Grub settings.

In order to avoid this it's easiest to use the Windows Vista installation DVD. Use the same method explained earlier to recover from a Windows XP installation: choose repair, get a command line then use the two commands:
bootrec. exe /fvanbr bootrec. exe /fvcboot
This will eradicate the Grub bootloader from the disk, allowing you to safely format, delete or re-use the Linux partition.

Using multiple disks

So far we've examined how to install more than one operating system on a single hard disk, but it is also possible to dual boot between two systems on two separate disks. Sadly, setting up a multi-boot, multi-disk system can be far more complicated than you might think. As an example, we'll explain how to take a PC with Vista on its hard disk and add a second disk running Linux.

The first step is, obviously, to install the new hard disk. While the PC case is open, though, we recommend temporarily disconnecting the first hard disk. This removes any risk of accidentally overwriting Vista with the new copy of Linux. Then boot from the Linux CD and install it as you would normally, partitioning the new hard disk to suit.

Once the process is finished, the PC will restart. It'll load a copy of Grub on the new hard disk that will, in turn, load Linux. Turn off the PC and recollect the Vista hard disk. Each disk will, if booted from, now load its own operating system. If you need to switch only rarely and have a Bios with a disk boot menu you could use that to choose operating systems. For a neater solution, though, one disk needs to be modified so that its bootloader gives access to the other disk.

You could modify the Vista bootloader, but it's far easier to change Grub. Set the computer's Bios to boot from the Linux disk fIrst - ifthere's no option you may need to reconnect the two disks so that the Linux disk appears higher in the list of hard disks. Once this is done, Linux will start up automatically on boot. Open a tenninal and type: sudogeditlboot/grub/fllenu.lst
Now we need to edit the Grub settings to include Windows. Scroll down to the entries that detail the various Linux startup modes, and add the following wldemeath them:
title Windows
root (hdl,O)
lIIakeactive
chain loader +1

This tells Grub to list an option for Windows that will look on the first (0 - Linux counts from zero) partition of the second (hd 1) hard disk and start another bootloader (hence the chainloader command) there. If your hard disk setup is different you may need to change the (hd1 ,0) value-normally if Vista is installed alone its bootloader will be in the first partition, so try (hd0,0) or (hd2,0) if (hd1 ,0) doesn't work. Save this file and then restart. Choosing Windows should send control to the other hard disk, which will start Vista. If you want you can go back to edit the default and timeout options in menu. lst as explained before.

Dual booting isn't always as simple as you might hope, but with a little patience and the right tools it's possible to set up an elegant system to choose between four or more operating systems should you need to. Just remember to type options carefully and, above all, keep those install discs close at hand.