Subject to limitations in some cases, you may boot the installation system from a Debian GNU/Linux CD-ROM, floppy disks, a partition on a hard disk, or from another machine via a local area network.
Boot parameters are Linux kernel parameters which are generally used to make sure that peripherals are dealt with properly. For the most part, the kernel can auto-detect information about your peripherals. However, in some cases you'll have to help the kernel a bit.
On S/390 you can append boot parameters in the parm file. This file can either
be in ASCII or EBCDIC format. Please read Device
Drivers and Installation Commands for more information about
S/390-specific boot parameters.
Full information on boot parameters can be found in the Linux BootPrompt
HOWTO; this section contains only a sketch of the most salient
parameters.
If this is the first time you're booting the system, try the default boot parameters (i.e., don't try setting arguments) and see if it works correctly. It probably will. If not, you can reboot later and look for any special parameters that inform the system about your hardware.
When the kernel boots, a message
Memory:
availk/totalk available
should be emitted early in the process. total should match the total amount of RAM, in kilobytes. If this doesn't match the actual of RAM you have installed, you need to use the mem=ram parameter, where ram is set to the amount of memory, suffixed with ``k'' for kilobytes, or ``m'' for megabytes. For example, both mem=65536k and mem=64m mean 64MB of RAM.
If your monitor is only capable of black-and-white, use the mono boot argument. Otherwise, your installation will use color, which is the default.
Again, full details on boot parameters can be found in the Linux BootPrompt
HOWTO, including tips for obscure hardware. Some common gotchas are
included below in Troubleshooting the
Install Process, Section 5.4.
The installation system recognizes a few boot arguments which may be useful. The effects of quiet and verbose are listed in Effects of Verbose and Quiet, Section 11.5.
The easiest route for most people will be to use a set of Debian CDs. If you
have a CD set, and if your machine supports booting directly off the CD, great!
Simply insert your CD, reboot, and proceed to the next chapter.
Note that certain CD drives may require special drivers, and thus be inaccessible in the early installation stages. If it turns out the standard way of booting off a CD doesn't work for your hardware, revisit this chapter and read about alternate kernels and installation methods which may work for you.
Even if you cannot boot from CD-ROM, you can probably install the Debian system components and any packages you want from CD-ROM. Simply boot using a different media, such as floppies. When it's time to install the operating system, base system, and any additional packages, point the installation system at the CD-ROM drive.
If you have problems booting, see Troubleshooting the Install Process, Section 5.4.
The biggest problem for people installing Debian for the first time seems to be floppy disk reliability.
The rescue floppy is the floppy with the worst problems, because it is read by the hardware directly, before Linux boots. Often, the hardware doesn't read as reliably as the Linux floppy disk driver, and may just stop without printing an error message if it reads incorrect data. There can also be failures in the Driver Floppies most of which indicate themselves with a flood of messages about disk I/O errors.
If you are having the installation stall at a particular floppy, the first thing you should do is re-download the floppy disk image and write it to a different floppy. Simply reformatting the old floppy may not be sufficient, even if it appears that the floppy was reformatted and written with no errors. It is sometimes useful to try writing the floppy on a different system.
One user reports he had to write the images to floppy three times before one worked, and then everything was fine with the third floppy.
Other users have reported that simply rebooting a few times with the same floppy in the floppy drive can lead to a successful boot. This is all due to buggy hardware or firmware floppy drivers.
If you have problems and the kernel hangs during the boot process, doesn't recognize peripherals you actually have, or drives are not recognized properly, the first thing to check is the boot parameters, as discussed in Boot Parameter Arguments, Section 5.1.
If you are booting with your own kernel instead of the one supplied with the installer, be sure that CONFIG_DEVFS is not set in your kernel. The installer is not compatible with CONFIG_DEVFS.
Often, problems can be solved by removing add-ons and peripherals, and then trying booting again.
There are, however, some limitations in our boot floppy set with respect to supported hardware. Some Linux-supported platforms might not be directly supported by our boot floppies. If this is the case, you may have to create a custom rescue disk (see Replacing the Rescue Floppy Kernel, Section 10.3), or investigate network installations.
If you have a large amount of memory installed in your machine, more than 512M, and the installer hangs when booting the kernel, you may need to include a boot argument to limit the amount of memory the kernel sees, such as mem=512m.
During the boot sequence, you may see many messages in the form can't find something, or something not present, can't initialize something, or even this driver release depends on something. Most of these messages are harmless. You see them because the kernel for the installation system is built to run on computers with many different peripheral devices. Obviously, no one computer will have every possible peripheral device, so the operating system may emit a few complaints while it looks for peripherals you don't own. You may also see the system pause for a while. This happens when it is waiting for a device to respond, and that device is not present on your system. If you find the time it takes to boot the system unacceptably long, you can create a custom kernel later (see Compiling a New Kernel, Section 9.5).
dbootstrap Problem Report
If you get through the initial boot phase but cannot complete the install,
dbootstrap's 'Report a Problem' menu choice may be helpful. It
creates dbg_log.tgz on a floppy, hard disk or nfs-mounted
filesystem. dbg_log.tgz details the system's state
(/var/log/messages, /proc/cpuinfo etc.).
dbg_log.tgz may provide clues as to what went wrong and how to fix
it. If you are submitting a bug report you may want to attach this file to the
bug report.
If you still have problems, please submit a bug report. Send an email to
submit@bugs.debian.org. You
must include the following as the first lines of the email:
Package: boot-floppies
Version: version
Make sure you fill in version with the version of the boot-floppies set that you used. If you don't know the version, use the date you downloaded the floppies, and include the distribution you got them from (e.g., ``stable'', ``frozen'', ``woody'').
You should also include the following information in your bug report:
architecture: s390
model: your general hardware vendor and model
memory: amount of RAM
scsi: SCSI host adapter, if any
cd-rom: CD-ROM model and interface type, e.g., ATAPI
network card: network interface card, if any
pcmcia: details of any PCMCIA devices
Depending on the nature of the bug, it also might be useful to report whether you are installing to IDE or SCSI disks, other peripheral devices such as audio, disk capacity, and the model of video card.
In the bug report, describe what the problem is, including the last visible kernel messages in the event of a kernel hang. Describe the steps that you did which brought the system into the problem state.
dbootstrap
dbootstrap is the name of the program which is run after you have
booted into the installation system. It is responsible for initial system
configuration and the installation of the ``base system''.
The main job of dbootstrap, and the main purpose of your initial
system configuration, is to configure essential elements of your system. For
instance, you may need to use certain ``kernel modules'', drivers which are
linked into the kernel. These modules include storage hardware drivers,
network drivers, special language support, and support for other peripherals
which are not automatically built in to the kernel you are using.
Disk partitioning, disk formatting, and networking setup are also facilitated
by dbootstrap. This fundamental setup is done first, since it is
often necessary for the proper functioning of your system.
dbootstrap is a simple, character-based application, designed for
maximum compatibility in all situations (such as installation over a serial
line). It is very easy to use. It will guide you through each step of the
installation process in a linear fashion. You can also go back and repeat
steps if you find you have made a mistake.
To navigate within dbootstrap, use:
If you are an experienced Unix or Linux user, press Left Alt-F2 to get
to the second virtual console. That's the Alt key on the
left-hand side of the space bar, and the F2 function key, at the same
time. This is a separate window running a Bourne shell clone called
ash. At this point you are booted from the RAM disk, and there is
a limited set of Unix utilities available for your use. You can see what
programs are available with the command ls /bin /sbin /usr/bin
/usr/sbin. Use the menus to perform any task that they are able to do
— the shell and commands are only there in case something goes wrong. In
particular, you should always use the menus, not the shell, to activate your
swap partition, because the menu software can't detect that you've done this
from the shell. Press Left Alt-F1 to get back to menus. Linux
provides up to 64 virtual consoles, although the rescue floppy only uses a few
of them.
Error messages are redirected to the third virtual terminal (known as
tty3). You can access this terminal by pressing Left
Alt-F3 (hold the Alt key while pressing the F3 function
key); get back to dbootstrap with Left Alt-F1.
These messages can also be found in /var/log/messages. After
installation, this log is copied to /var/log/installer.log on your
new system.
During the Base installation, package unpacking and setup messages are
redirected to tty4. You can access this terminal by pressing
Left Alt-F4; get back to dbootstrap with Left
Alt-F1.
The unpack/setup messages generated by debootstrap are saved in
/target/tmp/debootstrap.log when the installation is performed
over a serial console.
The first screen that dbootstrap will present you with is the
``Release Notes''. This screen presents the version information for the
boot-floppies software you are using, and gives a brief
introduction to Debian developers.
You may see a dialog box that says ``The installation program is determining
the current state of your system and the next installation step that should be
performed.''. On some systems, this will go by too quickly to read. You'll
see this dialog box between steps in the main menu. The installation program,
dbootstrap, will check the state of the system in between each
step. This checking allows you to re-start the installation without losing the
work you have already done, in case you happen to halt your system in the
middle of the installation process. If you have to restart an installation,
you will have to configure your keyboard, re-activate your swap partition, and
re-mount any disks that have been initialized. Anything else that you have
done with the installation system will be saved.
During the entire installation process, you will be presented with the main
menu, entitled ``Debian GNU/Linux Installation Main Menu''. The choices at the
top of the menu will change to indicate your progress in installing the system.
Phil Hughes wrote in the Linux
Journal that you could teach a chicken to install Debian!
He meant that the installation process was mostly just pecking at the
Enter key. The first choice on the installation menu is the next
action that you should perform according to what the system detects you have
already done. It should say ``Next'', and at this point the next step in
installing the system will be taken.
Did we tell you to back up your disks? Here's your last chance to save your old system. If you haven't backed up all of your disks, remove the floppy from the drive, reset the system, and run backups.
Installing Debian GNU/Linux 3.0 For S/390
version 3.0.23, 16 May, 2002