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LILO mini-HOWTO
Miroslav "Misko" Skoric, skoric at eunet dot yu v3.27, 2006-07-28

LILO is the most used Linux Loader for the x86 flavor of Linux; I'll call it Lilo rather than LILO here because I don't appreciate uppercase. This file describes some typical Lilo installations. It's intended as a supplement to the Lilo User's Guide. I think examples are informative even if your setup isn't much like mine. I hope this saves you trouble. Since Lilo's own documentation is very good, who's interested in the details is referred to /usr/doc/lilo* (once upon a time said gentlemen like Cameron Spitzer and Alessandro Rubini who have made early versions of this document)

This version of Lilo mini-HOWTO is based on work of Cameron Spitzer (cls@truffula.sj.ca.us) and Alessandro Rubini (rubini@linux.it). There are also contributions from Tony Harris (tony@nmr.mgh.harvard.edu) and Marc Tanguy (mtanguy@ens.uvsq.fr). Well, I have used materials from the authors mentioned - without changes - and added some pointers related to configuring LILO for using with Windows NT and Windows 2000. More detailed information about the activation of Windows NT/2000 from LILO menu, you may find in wonderfull Linux+WindowsNT <http://tldp.org/HOWTO/Linux+WinNT.html> mini-HOWTO.

  1. Introduction

Although the documentation found in Lilo's sources (the one installed in /usr/doc/lilo-version) is very comprehensive, most Linux users experience some trouble in building their own /etc/lilo.conf file. This document is meant to support them by giving the minimal information and by showing five sample installations:

  • The first example is the classical ``Linux and other'' installation.
  • The next one shows how to install Lilo on a hard drive connected as /dev/hdc that will boot as /dev/hda. This is usually needed when you install a new Linux drive from your own running system. This also tells how to boot from SCSI disks when your BIOS is modern enough.
  • The third example shows how to boot a Linux system whose root partition can't be accessed by the BIOS.
  • The next sample file is used to access huge disks, that neither the BIOS nor DOS can access easily (this one is somehow outdated).
  • The last example shows how to restore a damaged disk, if the damage resulted from installing another operating system).

The last three examples are by Cameron, cls@truffula.sj.ca.us, who wrote the original document. Alessandro rubini@linux.it doesn't run anything but Linux, so he can't check nor update them by himself. Needless to say, any feedback is welcome.

2. Background Information and Standard Installation

When Lilo boots the system, it uses BIOS calls to load the Linux kernel off the disk (IDE drive, floppy or whatever). Therefore, the kernel must live in some place that can be accessed by the bios. At boot time, Lilo is not able to read filesystem data, and any pathname you put in /etc/lilo.conf is resolved at installation time (when you invoke /sbin/lilo). Installation time is when the program builds the tables that list which sectors are used by the files used to load the operating system. As a consequence, all of these files must live in a partition that can be accessed by the BIOS (the files are usually located in the /boot directory, this means that only the root partition of your Linux system needs to be accessed via the BIOS).

Another consequence of being BIOS-based is that you must reinstall the loader (i.e., you must reinvoke /sbin/lilo) any time you modify the Lilo setup. Whenever you recompile your kernel and overwrite your old image you must reinstall Lilo.

2.1. Where Should I Install Lilo?

The boot= directive in /etc/lilo.conf tells Lilo where it should place its primary boot loader. In general, you can either specify the master boot record (/dev/hda) or the root partition of your Linux installation (is usually is /dev/hda1 or /dev/hda2).

If you have another operating system installed in your hard drive, you'd better install Lilo to the root partition instead of the MBR. In this case, you must mark the partition as ``bootable'' using the ``a'' command of fdisk or the ``b'' command of cfdisk. If you don't overwrite the master boot sector you'll find it easier to uninstall Linux and Lilo if needed.

Of course, you always have a way to avoid some "rules" like above. Well, you may install Lilo to the MBR even if you already have another operating system installed there. For example, if you installed Windows NT 4.0 as the first operating system on your machine, then NT's boot loader was placed into the MBR so you were able to boot NT without problems. After you installed Linux and chose to install Lilo to the MBR, Lilo rewrote NT's boot loader. Next time you boot your machine, you won't be able to boot NT. But, that is no problem. You should edit your /etc/lilo.conf and add a new entry for NT. Next time you re-boot your system, there will be the new added NT entry under Lilo menu. The same thing happened when I installed Windows 2000 instead of Windows NT.

2.2. How Should I Configure my IDE Hard Drives?

I personally don't use LBA or LARGE settings in the BIOS (but I only run Linux); they are horrible kludges forced on by design deficiencies in the PC world. This requires that the kernel lives in the first 1024 cylinders, but this is not a problem as long as you partition your hard drives and keep root small (as you should do anyways).

If your hard disk already carries another operating system, you won't be able to modify the BIOS settings, or the old system won't work any more. All recent Lilo distribution are able to deal with LBA and LARGE disk settings.

Note that the "linear" keyword in /etc/lilo.conf can help in dealing with geometry problems. The keyword instructs Lilo to use linear sector addresses instead of sector/head/cylinder tuples. Conversion to 3D addresses is delayed to run-time, therefore making the setup more immune to geometry problems.

If you have more than one hard disk and some of them are only used by Linux and are not involved in the boot process, you can tell your BIOS that they are not installed. Your system will boot more quickly and Linux will autodetect all the disks in no time. I often switch disks in my computers, but I never touch the BIOS configuration.

2.3. How Can I Interact at Boot Time?

When you see the Lilo prompt, you can hit the <Tab> key to show the list of possible choices. If Lilo is not configured to be interactive, press and hold the <Alt> or <Shift> key before the ``LILO'' message appears.

If you choose to boot a Linux kernel, you can add command-line arguments after the name of the system you choose. The kernel accepts many command-line arguments. All the arguments are listed in the ``BootPrompt-HOWTO'' by Paul Gortmaker, and I won't replicate it here. A few command line arguments, however, are particularly important and worth describing here:

  • root=: you can tell the Linux kernel to mount as root a different partition than the one appearing in /lilo.conf. For example, my system has a tiny partition hosting a minimal Linux installation, and I've been able to boot the system after destroying my root partition by mistake.
  • init=: version 1.3.43 and newer of the Linux kernel can execute another command instead of /sbin/init, as specified on the command line. If you experience bad problems during the boot process, you can access the bare system by specifying init=/bin/sh (when you are at the shell prompt you most likely will need to mount your disks: try ``mount -w -n -o remount /; mount -a'', and remember to ``umount -a'' before turning off the computer).
  • A number: by specifying a number on the kernel command line, you instruct init to enter a specific run-level (the default is usually 3 or 2, according to the distribution you chose). Refer to the init documentation, to /etc/inittab and to /etc/rc*.d to probe further.

2.4. How Can I Uninstall Lilo?

When Lilo overwrites a boot sector, it saves a backup copy in /boot/boot.xxyy, where xxyy are the major and minor numbers of the device, in hex. You can see the major and minor numbers of your disk or partition by running ``ls -l /dev//device''. For example, the first sector of /dev/hda (major 3, minor 0) will be saved in /boot/boot.0300, installing Lilo on /dev/fd0 creates /boot/boot.0200 and installing on /dev/sdb3 (major 8, minor 19) creates /boot/boot.0813. Note that Lilo won't create the file if there is already one so you don't need to care about the backup copy whenever you reinstall Lilo (for example, after recompiling your kernel). The backup copies found in /boot/ are always the snapshot of the situation before installing any Lilo.

If you ever need to uninstall Lilo (for example, in the unfortunate case you need to uninstall Linux), you just need to restore the original boot sector. If Lilo is installed in /dev/hda, just do ``dd if=/boot/boot.0300 of=/dev/hda bs=446 count=1'' (I personally just do ``cat /boot/boot.0300 > /dev/hda'', but this is not safe, as this will restore the original partition table as well, which you might have modified in the meanwhile). This command is much easier to run than trying ``fdisk /mbr'' from a DOS shell: it allows you to cleanly remove Linux from a disk without ever booting anything but Linux. After removing Lilo remember to run Linux' fdisk to destroy any Linux partition (DOS' fdisk is unable to remove non-dos partitions).

If you installed Lilo on your root partition (e.g., /dev/hda2), nothing special needs to be done to uninstall Lilo. Just run Linux' fdisk to remove Linux partitions from the partition table. You must also mark the DOS partition as bootable.

2.5. How to make a ram disk?

Notice: If you find the next section difficult to read, you may also look for the web page:
http://surfer.nmr.mgh.harvard.edu/partition/ramdisk.html where you would find the "original" of this contribution ...

by Tony Harris

16 Oct 2000

ram disk eenie-weenie HOWTO

If your root file system is on a device for which your kernel has no compiled-in driver, you will need to use lilo to load that driver as a module very early in the boot cycle. There are only two easy steps:

  • make a ram disk image with /mkinitrd
  • modify lilo.conf to point to the image

First, I cd over to /boot:

  System.map                  chain.b                module-info-2.2.16-3ext3
  System.map-2.2.16-3         initrd-2.2.16-3.img    vmlinux-2.2.16-3
  System.map-2.2.16-3ext3     vmlinux-2.2.16-3ext3
  vmlinuz                     kernel.h
  boot.b                      map                    vmlinuz-2.2.16-3
  bz.2.2.15.juke.Image        module-info            vmlinuz-2.2.16-3ext3
  bzImage-2.2.14              module-info-2.2.16-3

Here you can see that I have a 2.2.16-3 kernel and I have added a second kernel with ext3 support (vmlinuz-2.2.16-3ext3). There is already a ram disk image for my first kernel (initrd-2.2.16-3.img)

To make a new image for the second kernel, I type the following (stuff I type is in bold):

boot# mkinitrd initrd-2.2-16-3ext3.img 2.2.16-3ext3

mkinitrd is a shellscript that looks at the modules needed by my kernel, then makes an ext2 filesystem containing them. If we look inside the image we see this is the case:

boot# cat initrd-2.2.16-3ext3.img | gunzip > /tmp/myimage

boot# file /tmp/myimage

/tmp/myimage: Linux/i386 ext2 filesystem/

You do not have to look inside your image. Only making the image and modifying lilo.conf are necessary steps. However, discussion of the ramdisk image is provided for pedagogic purposes.

In order to look inside, I need to mount the image as though it were a

filesystem

boot# mount /tmp/myimage /mnt/tmp -t ext2 -o loop=/dev/loop3

boot# ls /mnt/tmp

bin dev etc lib linuxrc

boot# find /mnt/tmp

mnt/tmp/

mnt/tmp/lib/

mnt/tmp/lib/aic7xxx.o/

mnt/tmp/bin/

mnt/tmp/bin/sh/

mnt/tmp/bin/insmod/

mnt/tmp/etc/

mnt/tmp/dev/

mnt/tmp/dev/console/

mnt/tmp/dev/null/

mnt/tmp/dev/ram/

mnt/tmp/dev/systty/

mnt/tmp/dev/tty1/

mnt/tmp/dev/tty2/

mnt/tmp/dev/tty3/

mnt/tmp/dev/tty4/

mnt/tmp/linuxrc/

The most important part of this ram disk image is aic7xxx.o, which is my scsi module.

Finally, I move on to the last step, modifying /etc/lilo.conf:

Here is my entry in lilo.conf that corresponds to the kernel and image I just created:

image=boot/vmlinuz-2.2.16-3ext3/

label=linux.ext3

initrd=boot/initrd-2.2.16-3ext3.img/

read-only

root=dev/hdb3/

That's it. Run /lilo as root and reboot.

If you have problems, check out the kernel HOWTO. There are a couple things you need to have covered: you need your kernel modules compiled and living in /etc/conf.modules.

3. The Simple Configuration

Most Lilo installations use a configuration file like the following

one

boot = /dev/hda # or your root partition

  delay = 10        # delay, in tenth of a second (so you can interact)
  vga = 0           # optional. Use "vga=1" to get 80x50
  #linear           # try "linear" in case of geometry problems.

image = /boot/vmlinux # your zImage file

    root = /dev/hda1     # your root partition
    label = Linux        # or any fancy name
    read-only            # mount root read-only

other = /dev/hda4 # your dos partition, if any table = /dev/hda # the current partition table label = dos # or any non-fancy name

You can have multiple ``image'' and ``other'' sections if you want. It's not uncommon to have several kernel images configured in your lilo.conf, at least if you keep up to date with kernel development.

3.1. How to Deal with Big Kernels

If you compile a ``zImage'' kernel and it is too big to fit in half a megabyte (this is common with new 2.1 kernels), you should build a ``big zImage'' instead: ``make bzImage''. To boot a big kernel image nothing special is needed, but you need version 18 or newer of Lilo. If your installation is older, you should upgrade your Lilo package.

3.2. How to boot Windows NT from 'LILO boot:' menu

Here I will give you an order of routines you have to do if you want to have both Linux and NT entries under Lilo menu:

  • First of all, I would suggest you to install a fresh copy of Windows NT 4.0 on your hard disk. I suppose that you already made a backup of your important data, so the NT installation shouldn't be a problem. During the NT installation, setup is not going to ask you where to place NT's boot loader, so it would be placed into the MBR (Master Boot Record) of your hard disk. But, there is a possibility for a previous content of the MBR to remain within the MBR (especially any previous Lilo), so I would suggest you (before installation of NT) to boot the computer with a DOS floppy diskette having DOS version of FDISK. At the prompt a:\ just enter the command: fdisk /mbr and restart the computer again (without that floppy).
  • After you have successfully installed your NT, you will see that it uses the whole hard disk or a specific partition of the hard disk (depending on what you decided during the setup process). So, it is advisable to 'shrink' the partition where NT resides in order to make some free space on the disk. Onto that free space you will install your Linux. After you have your NT configured and running, you have to boot your computer using a floppy diskette with Partition Magic utility by Power Quest. It is a graphical tool able to see all partitions on all hard disks you have. The best thing is that you can make some changes with your partitions but not to destroy your existing data. One of the available changes is to make your existing partition(s) smaller, so to get some free space on the disk(s) for other purposes. Although you are advised to make a backup before you make any changes to the partitions, I usually practice to 'shrink' NT's partition before I installed anything but NT itself (so, if needed, a repetitive re-installation wouldn't be a problem). Well, Partition Magic (or any other similar utility you are familiar with) will shrink your NT's partition (either NTFS or FAT) to a smaller measure and place it to either the beginning or to the end of the previous measure. It means that you may choose to have your 'shrinked' NT partition at the beginning or at the end of your disk (I usually choose NT to be at the beginning, so the ending part of the disk will become a 'free space'). After the 'shrinking' is finished, you may re-boot your NT in order to check the new situation: you may use Windows Explorer or Disk Administrator for that.
  • So far so good. Next step is to install your Linux. Case you are familiar with RedHat distribution (I hope with other distros is the same or similar), you start by putting your installation CD in the drive and re-boot the computer). Well, when you are about to choose what type of installation it will be (Gnome or KDE Workstation, Custom, etc.) you may choose whatever you planned before, but I would suggest to install a Workstation at first. This is good because Linux setup will find automatically the free space on the (first) hard disk, make all partitions needed for Linux, format them properly, make majority of option by default so you won't have much pain during the setup (later, if you want, you may either to add missing components or re-install Linux as Custom over the existing linux partitions). Lilo should go to the MBR.
  • After it looks that Linux installation is finished, you are going to re-start the computer and there there you will only see Lilo with one Linux entry to boot (or maybe more than one Linux entry, in case your hardware is multi-processor one). But, don't panic! Your Windows NT is still there where you had installed it before Linux. You should become some familiar with Linux as soon as possible, in order to be able to find and edit your new /etc/lilo.conf file. When you open this file for the first time, you'll see that there is only one (or more) Linux entry. Well, you should know the exact position (read: a partition) where Windows NT has been installed, so you could add an appropriate entry into /etc/lilo.conf file. After you do that, restart Lilo and, after the next re-boot, you will have both 'linux' and 'nt' entries under Lilo menu.

3.3. How to boot Windows 2000 from 'LILO boot:' menu

Well, you may use the same procedure as described above. I suggest you to read Linux+WindowsNT <http://tldp.org/HOWTO/Linux+WinNT.html> mini-HOWTO that also talks about booting Windows 2000, which is installed on the same part of disk where Windows NT was before. There you'll find many useful details regarding various Linux+WinNT/2000/98 combinations.

4. Installing hdc to Boot as hda and Using bios=

Lilo allows to map the kernel image from one disk and instruct the BIOS to retrieve it from another disk. For example, it's common for me to install Linux on a disk I connect to hdc (master disk of secondary controller) and boot it as a standalong system on the primary IDE controller of another computer. I copied the installation floppy to a tiny partition, so I can run chroot in a virtual console to install hdc while I use the system to do something else.

The lilo.conf file I use to install Lilo looks like:

# This file must be used from a system running off /dev/hdc boot = /dev/hdc # overwrite MBR of hdc disk = /dev/hdc # tell how hdc will look like:

bios = 0x80 # the bios will see it as first drive delay = 0
vga = 0

image = /boot/vmlinux # this is on /dev/hdc1 root = /dev/hda1 # but at boot it will be hda1 label = Linux
read-only

This configuration file must be read by a Lilo running off /dev/hdc1. The Lilo maps that get written the boot sector (/dev/hdc) must refer to the files in /boot (currently installed as hdc); such files will be accessed under hda when this disk will be booted as a standalone system.

I call this configuration file /mnt/etc/lilo.conf.hdc (/mnt is where hdc is mounted during the installation. I install Lilo by invoking ``cd /mnt; chroot . sbin/lilo -C /etc/lilo.conf.hdc''. Refer to the manual page for chroot if this looks magic.

The ``bios='' directive in lilo.conf is used to tell Lilo what the BIOS thinks of your devices. BIOS calls identify floppy disks and hard drives with a number: 0x00 and 0x01 select the floppy drives, 0x80 and the following numbers select hard disks (old BIOS-es can only access two disks). The meaning of ``bios = 0x80 in the previous sample file is therefore ``use 0x80 in your BIOS calls for /dev/hdc''.

This Lilo directive can be handy in other situations, for example when your BIOS is able to boot from SCSI disks instead of IDE ones. When both IDE and SCSI devices are there, Lilo can't tell whether 0x80 will refer to one or the other because the user is able to choose it in the BIOS configuration menus, and the BIOS can't be accessed while Linux is running.

By default, Lilo assumes that IDE drives are mapped first by the BIOS, but this can be overridden by using instructions like these in /etc/lilo.conf:

disk = /dev/sda
bios = 0x80

5. Using Lilo When the BIOS Can't See the Root Partition

I have two IDE drives, and a SCSI drive. The SCSI drive can't be seen from BIOS. The Linux Loader, Lilo, uses BIOS calls and can only see drives that BIOS can see. My stupid AMI BIOS will only boot from "A:" or "C:" My root file system is on a partition on the SCSI drive.

The solution consists in storing the kernel, map file, and chain loader in a Linux partition on the first IDE. Notice that it is not necessary to keep your kernel on your root partition.

The second partition on my first IDE (/dev/hda2, the Linux partition used to boot the system) is mounted on /u2. Here is the /etc/lilo.conf file I used.

# Install Lilo on the Master Boot Record # on the first IDE.
#
boot = /dev/hda
# /sbin/lilo (the installer) copies the Lilo boot record # from the following file to the MBR location. install = /u2/etc/lilo/boot.b
#
# I wrote a verbose boot menu. Lilo finds it here. message = /u2/etc/lilo/message
# The installer will build the following file. It tells # the boot-loader where the blocks of the kernels are. map = /u2/etc/lilo/map
compact
prompt
# Wait 10 seconds, then boot the 1.2.1 kernel by default. timeout = 100
# The kernel is stored where BIOS can see it by doing this: # cp -p /usr/src/linux/arch/i386/boot/zImage /u2/z1.2.1 image = /u2/z1.2.1

label = 1.2.1
# Lilo tells the kernel to mount the first SCSI partition # as root. BIOS does not have to be able to see it.

root = /dev/sda1
# This partition will be checked and remounted by /etc/rc.d/rc.S

read-only
# I kept an old Slackware kernel lying around in case I built a # kernel that doesn't work. I actually needed this once. image = /u2/z1.0.9

          label = 1.0.9
          root = /dev/sda1
          read-only

# My DR-DOS 6 partition.
other = /dev/hda1

          loader=/u2/etc/lilo/chain.b
          label = dos
          alias = m

6. How do i know the BIOS number for my SCSI disks

The contribution from Marc Tanguy (mtanguy@ens.uvsq.fr), 2001-09-27

6.1. The theory

Actually, it exists two ways to know it :

If you have an adaptec scsi card (2940u2, 29160, 39160), you simply use the 'diagnose' mode (using BIOS v3.10.0 recommended). It must be activated in the scsi card BIOS menu. Then you just have to wait and see something like :

  ...     ID     LUN     Vendor      Product       Rev      Size     Sync     Bus    HD#
  ...     0      0       QUANTUM     ATLAS10K2     DDD6     17GB     160      16     80h
  ...     1      0       QUANTUM     ATLAS10K2     DDD6     17GB     160      16     81h
  ...     2      0       IBM         DDRS          DC1B     4GB      80       16     82h
  ...     3      0       IBM         DNES          SAH0     9GB      80       16     83h

If you don't own an adaptec card, you have to know what is the 'booting' disk (usually ID 0, but not necessary, it can be defined in the scsi card BIOS) where LILO is going to be found and start : this is the first disk so it has number 0x80. Then it's very simple, the BIOS follows the IDs.

By example :

ID 0 -> boot -> 0x80
ID 1 -> empty
ID 2 -> disk -> 0x81
ID 3 -> disk -> 0x82

or

ID 0 -> disk -> 0x81
ID 1 -> empty
ID 2 -> disk -> 0x82
ID 3 -> boot -> 0x80
ID 4 -> disk -> 0x83

This part doesn't care at all of what is installed on the scsi drives. But you should note that if you use an ID higher than the SCSI adapter it c an be a problem. So you should always try to set the SCSI adapter ID after the SCSI devices IDs.

6.2. How to swap linux and NT booting ?

OK, but NT must be the first disk to boot, so i want it in 0x80, but i already have LILO and a full ext2 only drive on 0x80 and my NT drive is in 0x83. How can i 'swap' linux and NT ? This a very easy : you just have to tell BIOS that NT drive is now 0x80 and the Linux drive is 0x83.

other=/dev/sdd1

        label=nt
        map-drive = 0x83
        to = 0x80
        map-drive = 0x80
        to = 0x83

This change will produce a warning :

Warning: BIOS drive 0x8? may not be accessible

but if you know what you are doing it will run without problem.

I used it on this configuration which has a Red Hat Linux 7.1 and a Windows 2000 Pro :

Name Flags Part Type FS Type [Label] Size (MB)

Disk Drive: /dev/sda - 0x80

  sda1        Boot        Primary   Linux ext2       [/boot]            24.68
  sda2                    Primary   Linux Swap                         139.83
  sda3                    Primary   Linux ext2       [/usr]           3150.29
  sda4                    Primary   Linux ext2       [/home]         15044.04

Disk Drive: /dev/sdb - 0x81

  sdb1                    Primary   Linux Swap                         139.83
  sdb2                    Primary   Linux ext2       [/]              3150.29
  sdb3                    Primary   Linux ext2       [/opt]           1052.84
  sdb4                    Primary   Linux ext2       [/public]       14015.88

Disk Drive: /dev/sdc - 0x82

  sdc1                    Primary   Linux ext2       [/var]           1052.84
  sdc2                    Primary   Linux ext2       [/tmp]            106.93
  sdc3                    Primary   Linux ext2       [/cache]         1052.84
  sdc4                    Primary   Linux ext2       [/chroot]        2352.44

Disk Drive: /dev/sdd - 0x83
sdd1 Boot Primary NTFS [WINDOWS_2000] 9162.97

My full /etc/lilo.conf :

boot=/dev/sda
map=/boot/map
install=/boot/boot.b
prompt
default=Linux
read-only
compact
image=/boot/vmlinuz
label=Linux
root=/dev/sdb2
other=/dev/sdd1
label=Windows
map-drive = 0x83
to = 0x80
map-drive = 0x80
to = 0x83

6.3. Miscellaneous

I just plugged a new scsi drive, and now LILO refuse to boot, what's going on ?

When you plug a disk, you must be careful with the IDs. If you add a drive between two already plugged disks the BIOS numbers are changed :

           Before            ---->             After
  scsi id -       - BIOS id        scsi id -          - BIOS id
  ID 0    - disk  - 0x80           ID 0    - disk     - 0x80
  ID 1    - empty                  ID 1    - new disk - 0x81
  ID 2    - disk  - 0x81           ID 2    - disk     - 0x82 !!

If you change the BIOS ids, you have to re-evaluate them.

7. Accessing Huge Disks When the BIOS Can't

Notice: 1GB is "Huge"? Well, once upon a time...

The system in my office has a 1GB IDE drive. The BIOS can only see the first 504 MB of the IDE. (Where MB means 2**10 bytes, not 10**6 bytes.) So I have MS-DOS on a 350 MB partition /dev/hda1 and my Linux root on a 120 MB partition /dev/hda2.

Hauke Laging (hauke@laging.de) and Bob Hall (bhall@hallfire.org) have noticed a small mistake above, so they've suggested a MB to be 2**20 bytes rather than 2**10 bytes. Thanks for correction. In addition, Hauke would like to learn more about what he called, "character codes on LILO startup, when LILO dies with LI, LI-, LIL- or whatever". I'd appreciate a contribution related to this issue or a valid web link to that.

Here it is (a contribution by Zohar Stolar, zohar@numericable.fr):

B. LILO boot error codes

http://www.tldp.org/HOWTO/Bootdisk-HOWTO/a1483.html <http://www.tldp.org/HOWTO/Bootdisk-HOWTO/a1483.html>

Thanks for link.

MS-DOS was unable to install itself correctly when the drive was fresh. Novell DOS 7 had the same problem. Luckily for me, "Options by IBM" forgot to put the "OnTrack" diskette in the box with the drive. The drive was supposed to come with a product called "OnTrack Disk Manager." If you only have MSDOS, I guess you have to use it.

So I made a partition table with Linux' fdisk. MSDOS-6.2 refused to install itself in /dev/hda1. It said something like ``this release of MS-DOS is for new installations. Your computer already has MS-DOS so you need to get an upgrade release from your dealer.'' Actually, the disk was brand new.

What a crock! So I ran Linux' fdisk again and deleted partition 1 from the table. This satisfied MS-DOS 6.2 which proceeded to create the exact same partition 1 I had just deleted and installed itself. MS-DOS 6.2 wrote its Master Boot Record on the drive, but it couldn't boot.

Luckily I had a Slackware kernel on floppy (made by the Slackware installation program "setup"), so I booted Linux and wrote Lilo over MS-DOS' broken MBR. This works. Here is the /etc/lilo.conf file I

used

boot = /dev/hda
map = /lilo-map
delay = 100
ramdisk = 0 # Turns off ramdisk in Slackware kernel timeout = 100
prompt

  disk = /dev/hda         # BIOS only sees first 500 MB.
     bios = 0x80          # specifies the first IDE.
     sectors = 63         # get the numbers from your drive's docs.
     heads = 16
     cylinders = 2100

image = /vmlinuz
append = "hd=2100,16,63"
root = /dev/hda2
label = linux
read-only
vga = extended
other = /dev/hda1
label = msdos
table = /dev/hda
loader = /boot/chain.b

After I installed these systems, I verified that the partition containing the zImage, boot.b, map, chain.b, and message files can use an msdos file system, as long as it is not "stackered" or "doublespaced." So I could have made the DOS partition on /dev/hda1 500 MB.

I have also learned that "OnTrack" would have written a partition table starting a few dozen bytes into the drive, instead of at the beginning, and it is possible to hack the Linux IDE driver to work around this problem. But installing would have been impossible with the precompiled Slackware kernel. Eventually, IBM sent me an "OnTrack" diskette. I called OnTrack's technical support. They told me Linux is broken because Linux doesn't use BIOS. I gave their diskette away.

8. Booting from a Rescue Floppy

Next, I installed Windows-95 on my office system. It blew away my nice Lilo MBR, but it left my Linux partitions alone. Kernels take a long time to load from floppy, so I made a floppy with a working Lilo setup on it, which could boot my kernel from the IDE.

I made the lilo floppy like so:

fdformat /dev/fd0H1440 # lay tracks on virgin diskette mkfs -t minix /dev/fd0 1440 # make file system of type minix mount /dev/fd0 /mnt # mount in the standard tmp mount point cp -p /boot/chain.b /mnt # copy the chain loader over lilo -C /etc/lilo.flop # install Lilo and the map on the diskette. umount /mnt

Notice that the diskette must be mounted when you run the installer so that Lilo can write its map file properly.

This file is /etc/lilo.flop. It's almost the same as the last one:

# Makes a floppy that can boot kernels from HD. boot = /dev/fd0
map = /mnt/lilo-map
delay = 100
ramdisk = 0
timeout = 100
prompt

  disk = /dev/hda     # 1 GB IDE, BIOS only sees first 500 MB.
     bios=0x80
     sectors = 63
     heads = 16
     cylinders = 2100

image = /vmlinuz
append = "hd=2100,16,63"
root = /dev/hda2
label = linux
read-only
vga = extended
other = /dev/hda1
label = msdos
table = /dev/hda
loader = /mnt/chain.b

Finally, I needed MS-DOS 6.2 on my office system, but I didn't want to touch the first drive. I added a SCSI controller and drive, made an msdos file system on it with Linux' mkdosfs, and Windows-95 sees it as "D:". But of course MSDOS will not boot off of D:. This is not a problem when you have Lilo. I added the following to the lilo.conf in Example 2.

other = /dev/sda1
label = d6.2
table = /dev/sda
loader = /boot/any_d.b

With this modification MSDOS-6.2 runs, and it thinks it is on C: and Windows-95 is on D:.

9. LILO after the installation of Mandrake Linux 9.1 on HP products

2003-11-19

9.1. Description of the products used in this experiment

Notice: Folks, that part is NOT a commercial for HP production of any means! In fact, a series of HP computers I have been using has delivered failures in power supply units, problems with hard disks etc. On the other side, laptop's batteries get exhausted earlier than expected. Other than these issues, HP machines are fine.

HP Omnibook 6000

A laptop computer Omnibook 6000 is equipped with a 'bootable' DVD drive and recently, at an ICT conference, I bought a bootable DVD-ROM with Mandrake Linux 9.1 installation. After booting the laptop with that bootable DVD, it gets directly to the Linux installation menu.

HP Vectra VL420 (used as a server)

In opposite, an HP Vectra VL420 doesn't have a DVD drive (it only has a CD drive), so the direct installation from that particular installation DVD is not possible. But, an option of making a bootable floppy disk for starting the installation procedure is possible. In fact, several boot images are available for those users who don't have (bootable or not) DVD drive. One of the images is a 'network' one. That means, in a local area network there has to be either a NFS, FTP or HTTP server from which the installation will take place.

HP Vectra VL420 (used as a workstation)

Another VL420 desktop system I also use, has a spare HDD from a previous Windows 2000 server installation (actually, that IDE disk was moved from the other computer where it was a primary one and here it is the second one disk for backup data). The nice things is that it has a HTTP and FTP servers installed (of course, usable if the system is boot from that disk). That was good so I could use one of these servers now.

So, I made a 'network' bootable floppy and booted the first Vectra VL420 (intended to be a Linux server) with it. After a while, it came to a point to choose the installation method (NFS or FTP or HTTP server). At first, I wanted to use the second 'spare' HTTP server at the other Vectra mentioned above, but regardless of what permission I tried to give to the 'Everyone' group of Windows users, I always got the following answer from the Linux setup:

Error: Couldn't get file ... (or something like that)

Then I tried to use the FTP 'spare' server from the second Vectra and at first it also asked for local and remote IP addresses. That time successfully, it started to load a part of the remote Linux files into its memory without any complaint. Soon after, it came to the very same position as Omnibook 6000 did: it got directly to the installation menu, asking a user to choose a language for the installation use.

>From that point, the setup process was almost the same...

I have chosen/confirmed the following items:

  • a language to use, besides English(American) as default: I added Unicode and Serbian (both Cyrillic and Latin); - a mouse and keyboard;
  • a security level - I accepted defaults: 'Standard' for laptop and 'Higher' for server;

The next important task was to choose one of DrakX partitioning

options
  • for laptop I chose the 'Use the free space on the Windows partition', because the laptop has one IDE hard disk and I wanted it to use a part of it for Linux (besides existing Windows 2000 Prof. already installed). Windows' Disk Management reported:
  Disk 0  15      MB      FAT     (HP Diagnostics or like)
          7.13    GB      FAT32   (C: "HPNOTEBOOK")
          20.80   GB      Free space

The two partitions (FAT & FAT32) were made during the installation procedure using HP's supplied installation CD's.

At the first moment, Linux setup complained that my Windows partition "was too fragmented" and required me to reboot under Windows, run the "defrag" utility, then restart the Mandrake Linux installation. The defragmentation process have taken cca. 1.5 hour to be completed! When restarted the setup, it wanted to use 7.13 GB Windows partition, instead of 20.80 GB. I chose to 'Use the free space'. Then it made partitions for Linux: /dev/hda5 and /dev/hda7.

  • for Vectra VL420 I used 'Custom disk partitioning' because there I had two SCSI disks, one of them running Windows 2000 Server already installed, and the other one I wanted to use entirely for a Linux server. BTW, I wasn't sure what the option 'Erase entire disk' would do during its next step (erase a whole disk or a partition?), although it also may be the proper solution too. DrakX recognized the two SCSI disks as sda and sdb and I chose sdb to install Linux. The first step was to 'Clear all' and after that to 'Auto allocate' the space on that second disk. Finally, after a 'Done' it appeared to make /dev/sdb1 and /dev/sdb6 Linux partitions.

9.2. What does LILO looks like on these HP products

HP Omnibook 6000

boot=/dev/hda
map=/boot/map
vga=normal
default="windows"
keytable=/boot/us.klt
prompt
nowarn
timeout=100
message=/boot/message
menu-scheme=wb:bw:wb:bw
image=/boot/vmlinuz

          label="linux"
          root=/dev/hda5
          initrd=/boot/initrd.img
          append="quiet devfs=mount acpi=off"
          read-only
  image=/boot/vmlinuz
          label="failsafe"
          root=/dev/hda5
          initrd=/boot/initrd.img
          append="failsafe devfs=nomount acpi=off"
          read-only
  other=/dev/hda2                                 <--- /dev/hda1 seems to be reserved for some HP diags.
          label="windows"
          table=/dev/hda
  other=/dev/fd0
          label="floppy"
          unsafe

HP Vectra VL420 (installed as a desktop client Linux system)

boot=/dev/hda
map=/boot/map
vga=normal
default="windows"
keytable=/boot/us.klt
prompt
nowarn
timeout=100
message=/boot/message
menu-scheme=wb:bw:wb:bw
image=/boot/vmlinuz

          label="linux"
          root=/dev/hda5
          initrd=/boot/initrd.img
          append="quiet devfs=mount acpi=off"
          vga=788                                 <--- that line is missing at laptop with LCD screen above.
          read-only
  image=/boot/vmlinuz
          label="linux-nonfb"
          root=/dev/hda5
          initrd=/boot/initrd.img
          append="devfs=mount acpi=off"
          read-only
  image=/boot/vmlinuz
          label="failsafe"
          root=/dev/hda5
          initrd=/boot/initrd.img
          append="failsafe devfs=nomount acpi=off"
          read-only
  other=/dev/hda1                                 <--- /dev/hda1 seems not to be reserved for HP diags here.
          label="windows"                                     There I have Windows 2000 Professional already
          table=/dev/hda                                  installed (probably without HP's supplied CD's).
  other=/dev/hdb1                                 <--- that is the spare disk with Windows 2000 Server.
          label="windows2"                            Actually I had some data on it and used it as a
          table=/dev/hdb                                  second, backup disk on that desktop workstation.
          map-drive=0x80                                  I have never tried to boot the computer from it, but
             to=0x81                                      Mandrake's setup offered it as a boot option.
          map-drive=0x81                                  (And that was useful as a FTP server, needed to install
             to=0x80                                      Mandrake Linux on the other box - without DVD drive too).
  other=/dev/fd0
          label="floppy"
          unsafe

HP Vectra VL420 (installed as a desktop Linux system with server features)

boot=/dev/sda <--- /dev/sda is the first SCSI disk where LILO resides (MBR). map=/boot/map
vga=normal
default="windows"
keytable=/boot/us.klt
prompt
nowarn
timeout=100
message=/boot/message
menu-scheme=wb:bw:wb:bw
image=/boot/vmlinuz

          label="linux"
          root=/dev/sdb1                          <--- /dev/sdb1 is the second SCSI disk where Linux resides.
          initrd=/boot/initrd.img
          append="quiet devfs=mount acpi=off"
          vga=788
          read-only
  image=/boot/vmlinuz
          label="linux-nonfb"
          root=/dev/sdb1
          initrd=/boot/initrd.img
          append="devfs=mount acpi=off"
          read-only
  image=/boot/vmlinuz-secure
          label="linux-secure"                        <--- something related to the Linux server security?
          root=/dev/sdb1
          initrd=/boot/initrd-secure.img
          append="quiet devfs=mount acpi=off"
          read-only
  image=/boot/vmlinuz
          label="failsafe"
          root=/dev/sdb1
          initrd=/boot/initrd.img
          append="failsafe devfs=nomount acpi=off"
          read-only
  other=/dev/sda1                                 <--- /dev/sda1 is the first partition on the first SCSI disk where Windows resides.
          label="windows"
          table=/dev/sda

9.3. Conclusions

>From the examples above, you could see that I have been using various computer forms with also various types of hard disk. Somewhere there is only one IDE drive, somewhere else there are two of them, otherwise there are a couple of SCSI drives etc. Regardless of that, I always tried to put LILO into the MBR - located on the first disk. Now it looks like that Linux finally managed to solve the old 1024 cyl problem. In fact, LILO seems to be capable to boot Linux regardless it is placed close to the rest of Linux partitions or not.

There are some other considerations related to the experiment above, but they are part of the other fine document: Linux+WindowsNT <http://tldp.org/HOWTO/Linux+WinNT.html> mini-HOWTO.

10. Bibliography

2006-07-28

Notice: I often participate to (inter)national ICT conferences in Serbia & Montenegro, as well as abroad, presenting papers and running tutorials. What I have been doing is to spread - as much as possible - the basic ideas and the useful mission of the amateur radio hobby and its possible usage in engineering education. You bet, whenever possible I want my readers to make it with Linux. Besides that, I have been writing various articles for a variety of scientific and other magazines. Here you have a list of the articles I have written, and the papers submitted to the conferences until now.

In case you want to re-publish or forward my volunteer paper works to some journals or other public media around, you are free to contact me. Some of my papers are written in Serbian Cyrillic, some of them are in English and some of them even combined!

  • "U prilog I.A.C.", MI (the youth scientists' organization newspaper), No. 69, 1990.
  • "U prilog I.A.C. (2)", MI (the youth scientists' organization newspaper), No. 70, 1990.
  • "Vise od radio-amaterskog hobija", Vojska, No. 163, 1995.
  • "Korak ka zvezdama", Vojska, No. 200, 1996.
  • "Die Gefahr von Innen - Internet gegen Amateurfunk", AMSAT-DL Journal, No. 4, Dez./Feb. 96/97.
  • "Kakva nam organizacija (ne) treba?", Radioamater, Feb. 1997.
  • "Kakva nam organizacija (ne) treba? (2)", Radioamater, Apr./May. 1997.
  • "Sateliti umiru padajuci", Vojska, No. 235, 1997.
  • "The Internet is not the Enemy", QST, Aug. 1998.
  • "Novi radio-amateri za novi vek", Antena, June 2000.
  • "Racunarske komunikacije putem radio-veza i zastita pristupa", Bezbednost, No. 3, 2000.
  • "Paket-radio - Racunarske komunikacije putem radio-veza", proceedings, "Info-Teh", Vrnjacka Banja, Serbia, 2001.
  • "Racunarske komunikacije putem radio-amaterskih veza", proceedings, "YU-Info", Kopaonik, Serbia, 2002.
  • "Computer Communications over radio", presentation, "Linux FEST", Belgrade, Serbia, 2002.
  • "Paket-radio - Radio-amaterske digitalne veze", proceedings, "Kongres JISA", Herceg Novi, Montenegro, 2002.
  • "Paket-radio (2) - Modemi za radio-veze", proceedings, "Info-Teh", Vrnjacka Banja, Serbia, 2002.
  • "Alternativne racunarske mreze", festival catalog, "INFOFEST", Budva, Montenegro, 2002.
  • "Alternative computer networks", proceedings, "TELFOR", Belgrade, Serbia, 2002.
  • "With rule and regulation improvements to the progress" proceedings, "TELFOR", Belgrade, Serbia, 2002.
  • "Racunarske komunikacije putem radio-amaterskih veza (2)", proceedings, "YU-Info", Kopaonik, Serbia, 2003.
  • "Racunarske komunikacije putem radio-amaterskih veza (3)", proceedings, "YU-Info", Kopaonik, Serbia, 2003.
  • "Paket-radio (3) - Programske mogucnosti na strani servera", proceedings, "Info-Teh", Vrnjacka Banja, Serbia, 2003.
  • "Paket-radio (4) - Legal rules and regulations in the amateur computer networks", proceedings, "Info-Teh", Vrnjacka Banja, Serbia, 2003.
  • "Packet-radio (2) - With rule and regulation improvements to the progress", proceedings, "Kongres JISA", Herceg Novi, Montenegro, 2003.
  • "Alternativne racunarske mreze (2)", festival catalog, "INFOFEST", Budva, Montenegro, 2003.
  • "Alternativne racunarske komunikacije putem radio-veza", Info M, 6-7/2003.
  • "Legal Rules and Regulations in the Amateur Radio Computer Networks", proceedings, "22nd ARRL and TAPR Digital Communications Conference", Hartford, CT USA, 2003.
  • "Favoritism", IEEE Potentials, Oct/Nov 2003
  • "Alternative computer networks (2)", proceedings, "TELFOR", Belgrade, Serbia, 2003.
  • "With rule and regulation improvements to the progress (2)" proceedings, "TELFOR", Belgrade, Serbia, 2003.
  • "XI Telekomunikacioni forum - TELFOR 2003", Info M, 8/2003.
  • "Aktivnosti organizacije IEEE Computer Society - YU Chapter" Info M, 8/2003.
  • "Yugoslavia IEEE Student Branch", IEEE Region 8 News, Vol. 7 No. 1, Feb/Mar 2004
  • "Radio-amaterske racunarske mreze", tutorial, "Info-Teh", Vrnjacka Banja, Serbia, 2004.
  • "Radio-amaterske racunarske mreze", tutorial, "Kongres JISA", Herceg Novi, Montenegro, 2004.
  • "The Amateur Radio as a Learning Technology in Developing Countries", proceedings, "ICALT/TEDC 2004", Joensuu, Finland, 2004.
  • "The Amateur Radio in Engineering Education", seminar, "IEEE-EESTEC Technical Conference 2004", Arcavacata di Rende (Cosenza), Italy, 2004.
  • "The Conference Low-Down", IEEE Potentials, Feb/Mar 2005
  • "ICALT 2004, IEEE Novi Sad SB, Serbia & Montenegro", IEEE Region 8 News, Vol. 8 No. 1, Mar 2005
  • "The Conference Low-Down", IEEE Potentials, Apr/May 2005
  • "The Amateur Radio Networking And Computing", proceedings, "PSU-UNS ICEE 2005", Novi Sad, Serbia, 2005
  • "Radio-amaterske racunarske mreze", tutorial, "Info-Teh", Vrnjacka Banja, Serbia, 2005 (intro: dr D. Surla, PMF)
  • "Radio-veze", round table session, "Kongres JISA", Herceg Novi, Montenegro, 2005.
  • "The New Amateur Radio University Network - AMUNET", proceedings, "9th WSEAS CSCC Multiconference", Vouliagmeni, Athens, Greece, 2005.
  • "The perspectives of the Amateur University Network - AMUNET", WSEAS Transactions on Communications, Vol 4, pp 834, Sep. 2005.
  • "Conferences in Serbia and Montenegro", IEEE Region 8 News, Vol. 8 No. 3, Sep 2005.
  • "The Conference Low-Down", IEEE Potentials, Dec 2005
  • "University Networking Through the Amateur Radio Communications", plenary lecture, "3rd WSEAS/IASME Int. Conf. on Engineering Education", Vouliagmeni, Athens, Greece, 2006.
  • "The New Amateur Radio University Network - AMUNET (Part 2)", proceedings, "10th WSEAS CSCC Multiconference", Vouliagmeni, Athens, Greece, 2006.
  • "University Networking Through the Amateur Radio Communications", tutorial, "10th WSEAS CSCC Multiconference", Vouliagmeni, Athens, Greece, 2006.

Besides these articles published and papers presented, I have been studying for an M.Sc. degree in computing. I am also the member of the following associations: IEEE Computer Society, IEEE Communications Society and ACM. In addition, I have been voluntarily working on establishing an academy computer network that would use the amateur radio stations as the media. Such networks exist somewhere else on the globe and I invite their administrators to contact me in order to cooperate.

11. Further Information

11.1. Copyright

Copyright (c) 2006 by Miroslav "Misko" Skoric, YT7MPB.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is available from http://www.fsf.org/licenses/fdl.html.

11.2. Disclaimer

Use the information in this document at your own risk. I disavow any potential liability of this document. Use of the concepts, examples, and/or other content of this document is entirely at your own risk.

All copyrights are owned by their owners, unless specifically noted otherwise. Use of a term in this document should not be regarded as affecting the validity of any trademark or service mark.

Naming of particular products or brands should not be seen as endorsements.

You are strongly recommended to take a backup of your system before major installation and backups at regular intervals.

11.3. News

In addition to the Lilo docs, there are a number of mini-howto's that can be useful for your needs. All of them are called ``Linux+foobarOS'', for some foobar-OS, they deal with coexistence of Linux and other operating system(s). For example, "NT OS Loader + Linux miniHOWTO" by Bernd Reichert, describes how to add an entry for Linux under existing Windows NT Loader's menu. Next, you have Linux+WindowsNT <http://tldp.org/HOWTO/Linux+WinNT.html> mini-HOWTO written by myself, covering how to add an entry for NT under existing Linux Lilo menu (more detailed than here). Also, "Multiboot-withLILO" describes how the various Windows flavors can be made to coexist with Linux.

This mini-HOWTO would be improved from time to time. If you think that the HOWTO on your Linux installation CD is some out-of-date, you may check for newest release on the Internet. It could be found within the main Linux Documentation Project <http://www.linuxdoc.org/> homepage or this one: Linux Documentation Project <http://www.tldp.org/>.

11.4. Credits

This version of mini-HOWTO can thanks to:

       Cameron Spitzer (cls@truffula.sj.ca.us)
       Alessandro Rubini (rubini@linux.it)
       Tony Harris (tony@nmr.mgh.harvard.edu)
       Marc Tanguy (mtanguy@ens.uvsq.fr)
       Dragomir Kalaba, a local Linux 'guru'

Any comments or suggestions can be mailed to my email address: skoric at eunet dot yu

11.5. HOWTO

These are intended as the primary starting points to get the background information as well as show you how to solve a specific problem. Some relevant HOWTOs are Bootdisk, Installation, SCSI and UMSDOS. The main site for these is the LDP archive <http://metalab.unc.edu/LDP/> at Metalab (formerly known as Sunsite).

11.6. Mini-HOWTO

These are the smaller free text relatives to the HOWTOs. Some relevant mini-HOWTOs are Backup-With-MSDOS, Diskless, LILO, Large Disk, Linux+DOS+Win95+OS2, Linux+OS2+DOS, Linux+Win95, Linux+WindowsNT, Linux+NT-Loader, NFS-Root, Win95+Win+Linux, ZIP Drive, FBB packet-radio BBS. You can find these at the same place as the HOWTOs, usually in a sub directory called mini. Note that these are scheduled to be converted into SGML and become proper HOWTOs in the near future.

11.7. Local Resources

In most distributions of Linux there is a document directory installed, have a look in the /usr/doc directory. where most packages store their main documentation and README files etc. Also you will here find the HOWTO archive ( /usr/doc/HOWTO) of ready formatted HOWTOs and also the mini-HOWTO archive ( /usr/doc/HOWTO/mini <file:///usr/doc/HOWTO/mini>) of plain text documents.

Many of the configuration files mentioned earlier can be found in the /etc directory. In particular you will want to work with the /etc/fstab file that sets up the mounting of partitions and possibly also /etc/mdtab file that is used for the md system to set up RAID.

The kernel source in /usr/src/linux <file:///usr/src/linux> is, of course, the ultimate documentation. In other words, use the source, Luke. It should also be pointed out that the kernel comes not only with source code which is even commented (well, partially at least) but also an informative documentation directory <file:///usr/src/linux/Documentation>. If you are about to ask any questions about the kernel you should read this first, it will save you and many others a lot of time and possibly embarrassment.

Also have a look in your system log file ( /var/log/messages) to see what is going on and in particular how the booting went if too much scrolled off your screen. Using tail -f /var/log/messages in a separate window or screen will give you a continuous update of what is going on in your system.

You can also take advantage of the /proc file system that is a window into the inner workings of your system. Use cat rather than more to view the files as they are reported as being zero length. Reports are that less works well here.

11.8. Web Pages

There is a huge number of informative web pages out there and by their very nature they change quickly so don't be too surprised if these links become quickly outdated.

A good starting point is of course the Linux Documentation Project <http://www.linuxdoc.org/> home page, or this one: Linux Documentation Project <http://www.tldp.org/>, an information central for documentation, project pages and much, much more.

Please let me know if you have any other leads that can be of interest.

12. Getting help

In the end you might find yourself unable to solve your problems and need help from someone else. The most efficient way is either to ask someone local or in your nearest Linux user group, search the web for the nearest one.

Another possibility is to ask on Usenet News in one of the many, many newsgroups available. The problem is that these have such a high volume and noise (called low signal-to-noise ratio) that your question can easily fall through unanswered.

No matter where you ask it is important to ask well or you will not be taken seriously. Saying just my disk does not work is not going to help you and instead the noise level is increased even further and if you are lucky someone will ask you to clarify.

Instead describe your problems in some detail that will enable people to help you. The problem could lie somewhere you did not expect. Therefore you are advised to list up the following information on your

system

Hardware

  • Processor
  • DMA
  • IRQ
  • Chip set (LX, BX etc)
  • Bus (ISA, VESA, PCI etc)
  • Expansion cards used (Disk controllers, video, IO etc)

Software

  • BIOS (On motherboard and possibly SCSI host adapters)
  • LILO, if used
  • Linux kernel version as well as possible modifications and patches
  • Kernel parameters, if any
  • Software that shows the error (with version number or date)

Peripherals

  • Type of disk drives with manufacturer name, version and type
  • Other relevant peripherals connected to the same busses

Remember that booting text is logged to /var/log/messages which can answer most of the questions above. Obviously if the drives fail you might not be able to get the log saved to disk but you can at least scroll back up the screen using the SHIFT and PAGE UP keys. It may also be useful to include part of this in your request for help but do not go overboard, keep it brief as a complete log file dumped to Usenet News is more than a little annoying.


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