Booting the Red Hat Linux Installer

The Red Hat Linux installer runs under Linux; therefore, you need to boot Linux on your PC before you can go through the installation steps. This initial version of Linux can come from the installer boot floppy or the frist CD-ROM. The initial Linux operating system, in turn, runs the Red Hat installation program, which prepares the disk partitions and copies all necessary files from the CD-ROM to the disk.

You can boot your PC with an initial version of the Linux operating system in one of the following ways:

Boot your PC from the first CD-ROM (this works only if your PC is bootable from the CD-ROM; most PCs can boot from the CD-ROM drive, as I explain a little later).
Load the initial Linux kernel by executing the AUTOBOOT.BAT command file (from the DOSUTILS directory of the CD-ROM) while your PC is running MS-DOS.
Boot your PC from the Red Hat installer boot floppy you created earlier.

The following sections describe these approaches to booting Linux and initiating the Red Hat installation.

Booting from the Red Hat Linux CD-ROM

Most new PCs can boot directly from the CD-ROM. To do so, you have to go into SETUP as the PC powers up. The exact steps for entering SETUP and setting the boot device depend on the PC, but they typically involve pressing a key such as F2. As the PC powers up, a brief message should tell you what key to press to enter SETUP. Once you are in SETUP, you can designate the CD-ROM drive as the boot device.

After your PC is set up to boot directly from the CD-ROM drive, place the first Red Hat Linux CD-ROM into the CD-ROM drive, and reboot the PC. The PC should power up and start the Linux kernel from the CD-ROM. After Linux starts from the CD-ROM, the Red Hat installation program begins to run. The section “Installing from the Red Hat Linux CD-ROM” describes this process in detail.

Starting the Red Hat Linux Installer from DOS

You can start Linux directly from the CD-ROM while your PC is running MS-DOS. An MS-DOS program called LOADLIN.EXE can load a Linux kernel into memory and begin running Linux. The Linux kernel itself is in another file. You do not need to understand all of the details about how LOADLIN starts Linux. In fact, the Red Hat CD-ROM provides a DOS batch file, AUTOBOOT.BAT, in the \DOSUTILS directory that runs LOADLIN with appropriate arguments.

You can use AUTOBOOT to start Linux directly from the CD-ROM only if your PC is running MS-DOS alone (not an MS-DOS window under Windows 95/98 or a command window under Windows NT/2000/XP). In addition, you must be able to use the CD-ROM from MS-DOS. If your PC runs Windows, select Shutdown from the Start menu, and click the button labeled Restart the Computer in MS-DOS Mode. From the DOS prompt, try to see the directory of the CD-ROM with the command DIR D: where D is the drive letter of the CD-ROM drive. If this works, you can start Linux directly from the CD-ROM. Otherwise, you have to use a boot floppy.

To start Linux, place the Red Hat CD-ROM in the CD-ROM drive, and use the following commands from the DOS prompt:

D:          (use the drive letter for the CD-ROM drive)
cd \dosutils
autoboot

After Linux starts, the Red Hat installation program begins to run. The section “Installing Linux from the Red Hat CD-ROM” describes this process in detail.

The AUTOBOOT.BAT file runs the LOADLIN program with two arguments: the name of a Linux kernel file and a file that contains an initial file system (known as initial RAM disk, or initrd, because this file system is loaded into memory). If the autoboot command gives you an error message, type the following command to run loadlin and to start Linux from the CD-ROM:

loadlin autoboot\vmlinuz initrd=autoboot\initrd.img ramdisk_size= 9216 %1 %2 %3 %4 %5 %5 %7 %8 %9

Booting from the Red Hat Installer Boot Floppy

To start Linux for installation, put the Red Hat boot floppy in your PC’s A drive and restart your PC. Your PC goes through its normal startup sequence, such as checking memory and running the ROM BIOS code. Then, the PC loads Linux from the floppy and begins running the Red Hat installation program.

Watching the Boot Process during Installation

A few moments after you start the boot process, an initial screen appears—the screen displays a welcome message and ends with a boot: prompt. The welcome message tells you that help is available by pressing one of the function keys, F1 through F5.

If you want to read the help screens, press the function key corresponding to the help you want. If you don’t press any keys, after a minute the boot process proceeds with the loading of the Linux kernel into the PC’s memory. To start booting Linux immediately, press Enter. After the Linux kernel loads, it automatically starts the Red Hat Linux installation program, which, in turn, starts the X Window System and provides a GUI for the installation.

Insider Insight

As the Linux kernel begins to run, various messages appear on the screen. These boot messages tell you whether or not the Linux kernel has detected your hardware. The messages typically flash by too quickly for you to follow. Afterward, the screen shows a dialog box with a welcome message and some helpful information about the installation. At this point, you can read the messages about your hardware by pressing Ctrl-Alt-F4—this switches the display to another virtual screen where all kernel messages appear in a form slightly different from what you see on the main installation screen. In particular, look for a message about the CD-ROM, because the kernel has to detect the CD-ROM to proceed with the rest of the installation. To return to the graphical installation screen, press Ctrl-Alt-F7.