install the SYSLINUX bootloader on a FAT filesystem
see also :
fdisk - mkfs
[-sfr] [-d directory]
[-o offset] device
add an example, a script, a trick and tips
no example yet ...
... Feel free to add your own example above to help other Linux-lovers !
is a boot loader for the Linux operating system which
operates off an MS-DOS/Windows FAT filesystem. It is
intended to simplify first-time installation of Linux, and
for creation of rescue and other special-purpose boot
In order to
create a bootable Linux floppy using Syslinux,
prepare a normal MS-DOS formatted floppy. Copy one or more
Linux kernel files to it, then execute the command:
This will alter
the boot sector on the disk and copy a file named
LDLINUX.SYS into its root directory.
On boot time,
by default, the kernel will be loaded from the image named
LINUX on the boot floppy. This default can be changed, see
the section on the syslinux configuration file.
If the Shift or
Alt keys are held down during boot, or the Caps or Scroll
locks are set, syslinux will display a lilo(8)
-style "boot:" prompt. The user can then type a
kernel file name followed by any kernel parameters. The
syslinux loader does not need to know about the
kernel file in advance; all that is required is that it is a
file located in the root directory on the disk.
supports the loading of initial ramdisks (initrd) and the
bzImage kernel format.
Install a "safe, slow and
stupid" version of syslinux. This version may
work on some very buggy BIOSes on which syslinux
would otherwise fail. If you find a machine on which the
-s option is required to make it boot reliably, please
send as much info about your machine as you can, and include
the failure mode.
Force install even if it appears unsafe.
RAID mode. If boot fails, tell the BIOS to boot the next
device in the boot sequence (usually the next hard disk)
instead of stopping with an error message. This is useful
for RAID-1 booting.
SYSLINUX control files in a subdirectory with
the specified name (relative to the root directory on the
Indicates that the filesystem
is at an offset from the base of the device or file.
All the configurable defaults in syslinux can be changed
by putting a file called syslinux.cfg in the root
directory of the boot floppy. This is a text file in either UNIX
or DOS format, containing one or more of the following items
(case is insensitive for keywords).
In the configuration file blank lines and comment lines beginning
with a hash mark (#) are ignored.
default kernel [ options ... ]
Sets the default command line. If syslinux boots
automatically, it will act just as if the entries after "default"
had been typed in at the "boot:" prompt.
If no configuration file is present, or no "default" entry is
present in the configuration file, the default is "linux auto".
NOTE: Earlier versions of SYSLINUX used to
append the string "auto" to whatever the user specified using the
DEFAULT command. As of version 1.54, this is no longer true, as
it caused problems when using a shell as a substitute for "init."
You may want to include this option manually.
append options ...
Add one or more options to the kernel command line. These
are added both for automatic and manual boots. The options are
added at the very beginning of the kernel command line, usually
permitting explicitly entered kernel options to override them.
This is the equivalent of the lilo(8)
append options ...
Indicates that if label is entered as the kernel to boot,
syslinux should instead boot image, and the
specified "append" options should be used instead of the ones
specified in the global section of the file (before the first
"label" command.) The default for image is the same as
label, and if no "append" is given the default is to use
the global entry (if any). Use "append -" to use no options at
all. Up to 128 "label" entries are permitted.
Labels are mangled as if they were DOS filenames, and must be
unique after mangling. For example, two labels "v2.1.30" and
"v2.1.31" will not be distinguishable.
The "image" doesn’t have to be a Linux kernel; it can be a
boot sector or a COMBOOT file (see below.)
If flag_val is 0, do not load a kernel image unless it has
been explicitly named in a "label" statement. The default is 1.
Indicates how long to wait at the "boot:" prompt until booting
automatically, in units of 1/10 s. The timeout is cancelled as
soon as the user types anything on the keyboard, the assumption
being that the user will complete the command line already begun.
A timeout of zero will disable the timeout completely, this is
also the default. The maximum possible timeout value is 35996;
corresponding to just below one hour.
serial port [ baudrate ]
Enables a serial port to act as the console. "port" is a number
(0 = /dev/ttyS0 = COM1, etc.); if "baudrate" is omitted, the baud
rate defaults to 9600 bps. The serial parameters are hardcoded to
be 8 bits, no parity, 1 stop bit.
For this directive to be guaranteed to work properly, it should
be the first directive in the configuration file.
Load a font in .psf format before displaying any output (except
the copyright line, which is output as ldlinux.sys itself is
loaded.) syslinux only loads the font onto the video card;
if the .psf file contains a Unicode table it is ignored. This
only works on EGA and VGA cards; hopefully it should do nothing
Install a simple keyboard map. The keyboard remapper used is
very simplistic (it simply remaps the keycodes received
from the BIOS, which means that only the key combinations
relevant in the default layout - usually U.S. English - can be
mapped) but should at least help people with AZERTY keyboard
layout and the locations of = and , (two special characters used
heavily on the Linux kernel command line.)
The included program keytab-lilo.pl(8) from the
distribution can be used to create such keymaps.
Displays the indicated file on the screen at boot time (before
the boot: prompt, if displayed). Please see the section below on
DISPLAY files. If the file is missing, this option is simply
If flag_val is 0, display the "boot:" prompt only if the
Shift or Alt key is pressed, or Caps Lock or Scroll lock is set
(this is the default). If flag_val is 1, always display
the "boot:" prompt.
Displays the indicated file on the screen when a function key is
pressed at the "boot:" prompt. This can be used to implement
pre-boot online help (presumably for the kernel command line
When using the serial console, press
<Ctrl-F><digit> to get to the help screens,
e.g. <Ctrl-F>2 to get to the f2 screen. For f10-f12,
hit <Ctrl-F>A, <Ctrl-F>B,
<Ctrl-F>C. For compatiblity with earlier versions,
f10 can also be entered as <Ctrl-F>0.
Display file format
DISPLAY and function-key help files are text files in either DOS
or UNIX format (with or without <CR>). In addition,
the following special codes are interpreted:
<FF> = <Ctrl-L> = ASCII 12
Clear the screen, home the cursor. Note that the screen is filled
with the current display color.
<SI><bg><fg>, <SI> =
<Ctrl-O> = ASCII 15
Set the display colors to the specified background and foreground
colors, where <bg> and <fg> are hex
digits, corresponding to the standard PC display attributes:
0 = black
8 = dark grey
1 = dark blue
9 = bright blue
2 = dark green
a = bright green
3 = dark cyan
b = bright cyan
4 = dark red
c = bright red
5 = dark purple
d = bright purple
6 = brown
e = yellow
7 = light grey
f = white
Picking a bright color (8-f) for the background results in the
corresponding dark color (0-7), with the foreground flashing.
colors are not visible over the serial console.
<CAN> = <Ctrl-X> = ASCII 24
If a VGA display is present, enter graphics mode and display the
graphic included in the specified file. The file format is an ad
hoc format called LSS16; the included Perl program "ppmtolss16"
can be used to produce these images. This Perl program also
includes the file format specification.
The image is displayed in 640x480 16-color mode. Once in graphics
mode, the display attributes (set by <SI> code
sequences) work slightly differently: the background color is
ignored, and the foreground colors are the 16 colors specified in
the image file. For that reason, ppmtolss16 allows you to specify
that certain colors should be assigned to specific color
Color indicies 0 and 7, in particular, should be chosen with
care: 0 is the background color, and 7 is the color used for the
text printed by SYSLINUX itself.
<EM>, <EM> = <Ctrl-U> =
If we are currently in graphics mode, return to text mode.
<Ctrl-P>..<Ctrl-W> = ASCII
These codes can be used to select which modes to print a certain
part of the message file in. Each of these control characters
select a specific set of modes (text screen, graphics screen,
serial port) for which the output is actually displayed:
Character Text Graph Serial
<DLE> = <Ctrl-P> = ASCII 16 No No No
<DC1> = <Ctrl-Q> = ASCII 17 Yes No No
<DC2> = <Ctrl-R> = ASCII 18 No Yes No
<DC3> = <Ctrl-S> = ASCII 19 Yes Yes No
<DC4> = <Ctrl-T> = ASCII 20 No No Yes
<NAK> = <Ctrl-U> = ASCII 21 Yes No Yes
<SYN> = <Ctrl-V> = ASCII 22 No Yes Yes
<ETB> = <Ctrl-W> = ASCII 23 Yes Yes Yes
<DC1>Text mode<DC2>Graphics mode<DC4>Serial
... will actually print out which mode the console is in!
<SUB> = <Ctrl-Z> = ASCII 26
End of file (DOS convention).
Comboot Images and other operating systems
This version of syslinux supports chain loading of other
operating systems (such as MS-DOS and its derivatives, including
Windows 95/98), as well as COMBOOT-style standalone executables
(a subset of DOS .COM files; see separate section below.)
Chain loading requires the boot sector of the foreign operating
system to be stored in a file in the root directory of the
filesystem. Because neither Linux kernels, boot sector images,
nor COMBOOT files have reliable magic numbers, syslinux
will look at the file extension. The following extensions are
none or other
Linux kernel image
COMBOOT image (not runnable from DOS)
Boot sector (DOS superblock will be patched in)
COMBOOT image (runnable from DOS)
For filenames given on the command line, syslinux will
search for the file by adding extensions in the order listed
above if the plain filename is not found. Filenames in KERNEL
statements must be fully qualified.
A COMBOOT file is a standalone executable in DOS .COM format.
They can, among other things, be produced by the Etherboot
package by Markus Gutschke and Ken Yap. The following
requirements apply for these files to be sufficiently
"standalone" for syslinux to be able to load and run them:
The program must not execute any DOS calls (since there is no
DOS), although it may call the BIOS. The only exception is that
the program may execute INT 20h (Terminate Program) to return to
the syslinux prompt. Note especially that INT 21h AH=4Ch,
INT 21h AH=31h or INT 27h are not supported.
Only the fields pspInt20 at offset 00h, pspNextParagraph at
offset 02h and pspCommandTail at offset 80h (contains the
arguments from the syslinux command line) in the PSP are
supported. All other fields will contain zero.
The program must not modify any main memory outside its 64K
segment if it returns to syslinux via INT 20h.
Syslinux currently doesn’t provide any form of API
for the use of COMBOOT files. If there is need, a future version
may contain an INT interface to some syslinux functions;
please contact me if you have a need or ideas for such an API.
Syslinux will attempt to detect if the user is trying to boot
on a 286 or lower class machine, or a machine with less than 608K
of low ("DOS") RAM (which means the Linux boot sequence cannot
complete). If so, a message is displayed and the boot sequence
aborted. Holding down the Ctrl key while booting disables this
The compile time and date of a specific syslinux version
can be obtained by the DOS command "type ldlinux.sys". This is
also used as the signature for the LDLINUX.SYS file, which must
match the boot sector
Any file that syslinux uses can be marked hidden, system
or readonly if so is convenient; syslinux ignores all file
attributes. The SYSLINUX installed automatically
sets the readonly attribute on LDLINUX.SYS.
SYSLINUX can be used to create bootdisk images for El
Torito-compatible bootable CD-ROMs. However, it appears that many
BIOSes are very buggy when it comes to booting CD-ROMs. Some
users have reported that the following steps are helpful in
making a CD-ROM that is bootable on the largest possible number
Use the -s (safe, slow and stupid) option to
Put the boot image as close to the beginning of the ISO 9660
filesystem as possible.
A CD-ROM is so much faster than a floppy that the -s option
shouldn’t matter from a speed perspective.
Of course, you probably want to use ISOLINUX instead. See the
documentation file isolinux.doc.
Booting from a FAT partition on a hard disk
SYSLINUX can boot from a FAT filesystem partition on a
hard disk (including FAT32). The installation procedure is
identical to the procedure for installing it on a floppy, and
should work under either DOS or Linux. To boot from a partition,
SYSLINUX needs to be launched from a Master Boot
Record or another boot loader, just like DOS itself would. A
sample master boot sector (mbr.bin) is included with
appreciate hearing of any problems you have with
SYSLINUX . I would also like to hear from you
if you have successfully used SYSLINUX ,
especially if you are using it for a distribution.
If you are
reporting problems, please include all possible information
about your system and your BIOS; the vast majority of all
problems reported turn out to be BIOS or hardware bugs, and
I need as much information as possible in order to diagnose
There is a
mailing list for discussion among SYSLINUX
users and for announcements of new and test versions. To
join, send a message to majordomo[:at:]linux.kernel[:dot:]org with the
in the body of
the message. The submission address is
keytab-lilo.pl, fdisk , mkfs ,
page is a modified version of the original syslinux
documentation by H. Peter Anvin <hpa[:at:]zytor[:dot:]com>. The
conversion to a manpage was made by Arthur Korn