#ifdef MAIN
Welcome to the boot loader of UHU-Linux 1.2 ☺
#else
#ifdef INSTALLER
Welcome to the installer of UHU-Linux 1.2 ☺
#else
Welcome to the installer floppy disk of UHU-Linux 1.2 ☺
#endif
#endif
Help is available in the following topics:
- Using the help (you can also press F1
again to get there)
- Using the boot loader, available keys
- Description of the options
- The most important boot parameters to control
the Linux system
To navigate in the help use the following keys:
Up: scroll upwards, select previous link
Down: scroll downwards, select next link
Left, Backspace: back to the previous help page
Right, Enter, Space: follow link
Page Up: scroll one page upwards
Page Down: scroll one page downwards
Home: jump to the top of the page
End: jump to the bottom of the page
Esc: leave the help
The help is context sensitive, which means that the opening page depends
on the item last used and on the boot parameter being edited. By following
the links, however, it's always possible to reach any help page.
Back to the main menu.
Use Up and Down arrows, Page Up and
Page Down to select the system to be booted.
Use the letters, digits, symbols,
space, left and right arrows, Home and
End, Backspace and Delete to edit the
boot parameters.
Press Enter to boot the selected entry.
F1 brings up the Help.
With F2 ACPI can be turned off.
Using F3 debug mode can be
activated.
F4 lets you choose between English and Hungarian
language and keyboard layout.
#ifndef MAIN
F5 lets you set the installer's video mode.
#endif
With F10 you can power off the computer. It doesn't work on
some machines.
Alt+SysRq+O is a hotkey combo for power
off, while Alt+SysRq+B immediately reboots the
system. ☠ Warning! Do not use these under VMware, except if you exactly
know what you're doing!
Esc switches to the text interface
of the GRUB boot loader. Here you can not only launch the existing
entries but also boot an arbitrary file.
Back to the main menu.
Pressing Esc leaves the graphical screen and takes you to the text
interface of GRUB.
#ifdef BOOTFLOPPY
The GRUB with network support only contains the
text interface.
#endif
Text mode GRUB has a much more old-fashioned look (accented
letters don't appear correctly, only English (American) keyboard layout is
supported and it only speaks English). In the mean time, it is more powerful
than the graphical one, since here not only the already existing entries can
be booted, but other ones can be set up too.
The following topics exist about details on GRUB's text
mode:
- Using the Text Mode
- Keywords of GRUB
- Partition and File Names
- Tab Completion
Further documentation is available within the grub package
as an info page.
Back to the Keys.
In the text menu system press e to display the details of
the selected option. You get one or more rows. Example:
kernel (hd0,0)/boot/bzImage
initrd (hd0,0)/boot/initrd
To alter a line, select it and perss e again. Press
Enter to confirm the changes you made or Esc to cancel
them. Once you're done with it, you can edit other lines as well. Press
d to delete a line, o and O to insert a new line
above or below the current one. E.g. the lines above can easily be altered
to this:
kernel (hd1,2)/boot/bzImage
initrd (hd1,2)/boot/initrd
Finally the command list can be booted by pressing b.
In the menu pressing c takes you to command line mode. Here
you can type help to get help about the commands. Esc
brings you back to the menu.
Back to the Text Mode of GRUB.
The kernel keyword is used to give the kernel, e.g.:
kernel (hd0,4)/boot/bzImage
Kernel options may be given too, e.g.:
kernel (hd0,4)/boot/bzImage debug acpi=off vga=4
To specify an initial ramdisk, use the initrd command:
initrd (hd0,4)/boot/initrd
A different boot loader can be loaded by the chainloader
command, e.g.:
chainloader (hd0,0)+1
To launch the specified system, type boot in command line
mode, or press b in the menu.
For further details type help in command line mode.
Back to the Text Mode of GRUB.
To name a disk or a partition use following expressions using parentheses:
(fd0) -- first floppy disk
(fd1) -- second floppy disk
(cd) -- CD (in case GRUB was booted from CD)
(hd0) -- first hard disk
(hd0,0) -- first primary partition of first hard disk
(hd0,1) -- second primary partition of first hard disk
(hd0,2) -- third primary partition of first hard disk
(hd0,3) -- fourth primary partition of first hard disk
(hd0,4) -- first logical partition of first hard disk
(hd0,5) -- second logical partition of first hard disk
...
(hd1) -- second hard disk
(hd1,0) -- first partition of second hard disk
...
(hd2) -- third hard disk
...
...
(nd) -- TFTP server (only in network aware GRUB)
Reading from CD is only supported if the BIOS booted this
GRUB from CD.
The device identifier should be followed by the file to be loaded.
Here are two basic possibilites:
- Use file name, e.g. /boot/bzImage. GRUB is
able to read FAT, Minix, Ext2, Ext3,
ReiserFS, JFS, XFS and iso9660 file
systems, but not NTFS. Use absolute path, and use / as
path separator regardless of the file system, \ is incorrect.
- List of blocks, e.g. +1 means the first block of the
partition or drive.
Back to the Text Mode of GRUB.
When typing an option in GRUB's text mode (both after pressing e on
a particular row to edit, and in command line mode) Tab helps us to
complete the line.
Example:
Hitting Tab on an empty line lists the available keywords.
Type
ker
and press Tab again. This completes the word to
kernel. Type the opening parenthesis:
kernel (
Tab again shows the available drives. Type hd0:
kernel (hd0
and Tab again. This time the partitions are listed along
with their file systems' type. Type the partition, the closing parenthesis
and a slash:
kernel (hd0,4)/
Here Tab completes on file names so it's easy to find the
required file. E.g. if we have typed:
kernel (hd0,4)/boot/bz
then most likely Tab will complete to this:
kernel (hd0,4)/boot/bzImage
Back to the Text Mode of GRUB.
F4 lets you choose between English and Hungarian language and
keyboard layout.
Back to Keys.
#ifdef MAIN
By selecting one of the offered boot options you can boot the corresponding
operating system installed to your computer. To control which options
appear, edit /boot/grub/menu.lst in your running UHU-Linux system.
#endif
#ifdef BOOTFLOPPY
- Installation from the first partition
- GRUB with network support
- Smart Boot Manager
- FreeDOS
#endif
#ifdef INSTALLER
- Installation
- Rescue system
#endif
- Memory test
Back to Main Menu.
#ifdef BOOTFLOPPY
This option launches the installer of UHU-Linux in case the two necessary
files (boot/bzImage and boot/initrd on the CD) were
previously copied to the boot directory of the first partition of
the first hard disk. On typical DOS and Windows installations this means
they were copied to C:\boot\bzImage and C:\boot\initrd.
The partition has to contain FAT or some Linux file system,
as GRUB is unable to read NTFS.
If you copied these two files to another partition, then press
Esc to enter the text interface of
GRUB where an alternate path can be specified as well.
Back to the Available Boot Options.
For technical reasons two different version of GRUB are present on
the boot floppy.
The currently running GRUB doesn't contain network support,
however, due to its lower memory needs it is able to display graphical
screen.
Network aware GRUB has support for about thirty different
kind of network cards, is able to perform DHCP requests to get the
host's settings, and load files from a TFTP server. However it
needs more memory, and unfortunately this along with the graphical support
doesn't fit in PC's base memory, hence we only have the text interface.
The first option of the network aware GRUB, UHU-Linux From
Network firsts asks for an IP address via DHCP, then fetches
/tftpboot/bzImage and /tftpboot/initrd using
TFTP. It's possible to edit the options, so different filenames can
be given too.
Back to the Available Boot Options.
The Smart Boot Manager option loads the boot manager with the same
name. Smart Boot Manager offers you to choose from all the hard disk
partitions, floppy and CD drives.
If you like this boot loader, install the UHU package sbm
and use the command sbminst to install this into your hard drive,
replacing GRUB.
For further information, visit
http://btmgr.sourceforge.net/.
Back to the Available Boot Options.
Using FreeDOS takes you to a minimal FreeDOS system.
Here fdisk lets you partition your hard drive, while
format can create a file system.
Using basic DOS file commands you can copy the boot/bzImage
and boot/initrd files from your CD (usually it's called
D:, but a different letter is also possible) to the FAT file system
in your hard disk.
Back to the Available Boot Options.
#endif
#ifdef INSTALLER
Choose Installation to begin installing your UHU-Linux from CD.
Back to the Available Boot Options.
Rescue System takes you to a basic Linux system where you can
repair your main Linux system or perform some other minor operations.
Alt plus function keys switch among different text
consoles.
Back to the Available Boot Options.
#endif
Memtest86+ checks the computer's memory.
Unfortunately there are quite a lot of computers around that have
faulty memory modules. Such a computer is, of course, unable to operate
correctly.
This program runs and tests your memory again and again as long as
it is stopped. In case of faulty hardware usually at least one error occures
within an hour, which is printed on the big blue part of the screen that is
emtpy at the beginning. However, the longer you leave this program running
(for several days if possible) the more sure you can be that the memory
modules are correct.
If an error is displayed, it is still not sure that the memory
moduls are bad, it's possible that the motherboard, processor or other
component of the system is faulty. In most of the cases, however, it is the
memory that misbehaves.
In case memory test shows errors (maybe only one error during some
days) it's important to replace the faulty component of the system as soon
as possible. Using a computer that is not able to correctly execute the
commands of the operating system can easily lead to serious data loss or
full corrpution of your file system.
Having the machine overclocked can also be a reason of failure.
Reset these values to their original factory value and repeat the test. If
the errors occur again then the faulty component (most likely a memory
module) has to be replace.
#ifdef INSTALLER
This menu item will be available from within the boot loader of the
installed system, unless you choose not to install the memtest86+
package.
#endif
For further information visit http://www.memtest.org/.
Back to the Available Boot Options.
Description is available on the following boot parameters:
acpi -- power management
debug -- debug mode
#ifndef MAIN
layout -- graphical resolution of the installer
LANG -- the language of the installer
#endif
ide -- the way IDE disks are accessed
#ifndef INSTALLER
3, 5 -- text/graphical mode
#endif
The most common parameters can be set by the function keys, the less
common ones have to be typed manually.
There are plenty other options as well, it would be impossible to
list them all. These are mainly parameters to the Linux kernel, but
#ifndef MAIN
e.g. debug is an option of both the kernel and the installer,
while layout and LANG are only used by the installer.
#else
sometimes influence the behavior of a system utility.
#endif
These parameters only have any affect if Linux is booted.
Back to the Main Menu.
#ifndef MAIN
If the installer cannot find a suitable graphical mode, try setting
vesa first. If this doesn't work either, choose vga. The
corresponding parameters are:
layout=vesa -- VESA mode
layout=vga -- VGA mode
The values can also be selected with F5.
Back to the Boot Parameters.
LANG sets the language of the installer. Possible values are:
LANG=en_US -- the installer runs in English
LANG=hu_HU -- the installer runs in Hungarian
The default is the value that GRUB uses, which can be set with
F4.
Back to the Boot Parameters.
#endif
In case the debug option is given, UHU-Linux kernel prints debug
message to the
#ifdef MAIN
screen.
#else
screen and the installer also runs in debug mode.
Having finished the installation, press Alt+F5,
Alt+F6, Alt+F7 and
Alt+F8 to switch to the virtual console No 5-8, and exit
from the shell in each of them (e.g. by pressing Ctrl+D).
#endif
This parameter can also be turned on with F3.
Back to the Boot Parameters.
The old way of accessing power management features of computers is to use
APM (Advanced Power Management).
The newer technology is called ACPI (Advanced Configuration and
Power Interface). ACPI is actually much more than just power management,
some new computers cannot even be booted without ACPI support, or it leads
to IRQ problems. Unfortunately sometimes it is ACPI itself that causes
problems (IRQ conflict, freeze), usually due to faulty BIOS
implementations. (A BIOS upgrade often helps.)
There are three basic choices:
- use ACPI (needs BIOS support)
- use APM (needs BIOS support)
- none of them
The recommended and the default is ACPI.
Options to control ACPI:
- acpi=on -- turns on ACPI support (default of UHU-Linux)
- acpi=force -- turns on ACPI even if BIOS seems buggy
- acpi=ht -- only use ACPI for HyperThreading
- acpi=off -- turns off ACPI
Some values can be selected by pressing F2.
If the computer doesn't support ACPI or it is turned off then APM
automatically takes its place, in case BIOS supports that one. To disable
APM use the option noapm.
Back to the Boot Parameters.
If problems arise with IDE disks, try disabling DMA mode with this option:
ide=nodma
Back to the Boot Parameters.
#ifndef INSTALLER
Use on digit to give the runlevel.
3 -- runlevel 3: text mode
5 -- runlevel 5: graphical mode
The default is stored in the booted Linux system, in
/etc/inittab.
Back to the Boot Parameters.
#endif