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<TD vAlign=bottom align=right><FONT size=+3>SYSLINUX </FONT></TD>
<TD width=165 rowSpan=2><IMG height=180 alt=[tux]
src="SYSLINUX - The Easy-to-use Linux Bootloader.files/tuxsmall.gif"
width=163></TD>
<TR>
<TD vAlign=top align=right><FONT size=+1>by H. Peter
Anvin</FONT></TD></TR></TBODY></TABLE><BR clear=all><BR>
<CENTER>[ <A href="http://syslinux.zytor.com/index.php">home</A> | <A
href="http://syslinux.zytor.com/download.php">download</A> | <A
href="http://syslinux.zytor.com/faq.php">SYSLINUX</A> | <A
href="http://syslinux.zytor.com/pxe.php">PXELINUX</A> | <A
href="http://syslinux.zytor.com/iso.php">ISOLINUX</A> | <A
href="http://syslinux.zytor.com/memdisk.php">MEMDISK</A> | <A
href="http://syslinux.zytor.com/screenshots.php">screen shots</A> | <A
href="http://syslinux.zytor.com/hardware.php">hardware</A> | <A
href="http://syslinux.zytor.com/history.php">changelog</A> | <A
href="mailto:syslinux@zytor.com">contact</A> ]</CENTER><BR><FONT
face=trebuchet,times><FONT size=+1><B>{ SYSLINUX Questions }</B></FONT>
<UL>
<LI><A href="http://syslinux.zytor.com/faq.php#whatis">What is SYSLINUX?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#whatisnot">What is SYSLINUX
not?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#bootable">How do I create a
bootable floppy?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#config">How can I configure
SYSLINUX?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#large">Can SYSLINUX handle
large (&gt;500K) bzInage kernels?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#format">What is the DISPLAY
file format?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#otherOS">Can SYSLINUX boot
other operating systems?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#comboot">What are COMBOOT
files?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#novice">What protections exist
in SYSLINUX?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#bootCDs">Does SYSLINUX support
bootable CDs?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#harddrive">Can I use SYSLINUX
on a hard drive?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#bugs">What Bugs are Outstanding
in SYSLINUX?</A>
<LI><A href="http://syslinux.zytor.com/faq.php#feedback">How can I Give
Feedback on SYSLINUX?</A> </LI></UL><A name=whatis><B><FONT size=+1>{ What is
SYSLINUX? }</FONT></B></A>
<BLOCKQUOTE>SYSLINUX 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 disks.
<P>SYSLINUX can be used, when properly set up, to completely eliminate the
need for distribution of raw diskette images for boot floppies. A SYSLINUX
floppy can be manipulated using standard MS-DOS (or any other OS that can
access an MS-DOS filesystem) tools once it has been created. </P></BLOCKQUOTE><A
name=whatisnot><B><FONT size=+1>{ What SYSLINUX is Not... }</FONT></B></A>
<BLOCKQUOTE>SYSLINUX is probably not suitable as a general purpose boot
loader. It can only boot Linux from a FAT filesystem, and not, for example,
ext2. Since a native Linux implementation will typically use ext2, another
boot loader (e.g. LILO) is probably more suitable. In a system which actually
contains DOS or Windows, LOADLIN may be simpler to use.
<P>However, SYSLINUX has shown itself to be quite useful in a number of
special-purpose applications. </P></BLOCKQUOTE><A name=bootable><B><FONT
size=+1>{ How do I Create a Bootable Floppy? }</FONT></B></A>
<BLOCKQUOTE>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 DOS command:
<BLOCKQUOTE><CODE>syslinux [-s] a:</CODE> </BLOCKQUOTE>(or whichever drive
letter is appropriate; the [] meaning -s is optional)
<P>If you're running in a Win95/98/ME DOS box, you should execute the command
<CODE><B>lock a:</B></CODE> first. If you're running in a WinNT/2K DOS box,
you will probably get a dialog box about not getting exclusive access and with
Abort/Retry/Ignore buttons; people have reported that selecting "Ignore" makes
the command complete correctly.
<P>Under Linux, execute the command:
<BLOCKQUOTE><CODE>syslinux [-s] [-o offset] /dev/fd0</CODE> </BLOCKQUOTE>(or,
again, whichever device is the correct one.)
<P>This will alter the boot sector on the disk and copy a file named
LDLINUX.SYS into its root directory.
<P>The <CODE>-s</CODE> option, if given, will 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
<CODE>-s</CODE>option is required to make it boot reliably, please send as
much info about your machine as you can, and include the failure mode.
<P>The <CODE>-o</CODE> option is used with a disk image file and specifies the
byte offset of the filesystem image in the file.
<P>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 config file.
<P>If the Shift or Alt keys are held down during boot, or the Caps or Scroll
locks are set, SYSLINUX will display a LILO-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.
</P></BLOCKQUOTE><A name=config><B><FONT size=+1>{ How do I Configure SYSLINUX?
}</FONT></B></A>
<BLOCKQUOTE>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; upper case is used here
to indicate that a word should be typed verbatim):
<P>All options here applies to PXELINUX as well as SYSLINUX unless otherwise
noted. See pxelinux.doc for additional information on PXELINUX.
<P><A name=#CMD_DEFAULT><B>DEFAULT</B> <I>kernel options...</I></A>
<BLOCKQUOTE>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, except that the option "auto" is automatically added,
indicating an automatic boot.
<P>If no configuration file is present, or no DEFAULT entry is present in
the config file, the default is kernel name "linux", with no options.
</P></BLOCKQUOTE><B>APPEND</B> <I>options...</I>
<BLOCKQUOTE>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 "append"
option. </BLOCKQUOTE><B>IPAPPEND</B> <I>flag_val</I> <FONT
color=#ffc0c0>[PXELINUX only]</FONT>
<BLOCKQUOTE>The IPAPPEND option is available only on PXELINUX, and indicates
(if the flag value is 1) that an option of the following format should be
generated and added:
<BLOCKQUOTE><CODE><NOBR>ip=&lt;client-ip&gt;:&lt;boot-server-ip&gt;:&lt;gw-ip&gt;:&lt;netmask&gt;</NOBR>
</CODE></BLOCKQUOTE>... based on the input from the DHCP/BOOTP or PXE boot
server. </BLOCKQUOTE><B>LABEL</B> <I>label</I>
<BLOCKQUOTE><B>KERNEL</B> <I>image</I><BR><B>APPEND</B>
<I>options...</I><BR><B>IPAPPEND</B> <I>flag_val</I> <FONT
color=#ffc0c0>[PXELINUX only]</FONT>
<P>Indicates that if "label" is entered as the kernel to boot, SYSLINUX
should instead boot "image", and the specified APPEND and IPAPPEND 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). Up to 128 LABEL entries are permitted. (for ISOLINUX, 64 LABEL
entries.)
<P>Note that LILO uses the syntax: <PRE>image = mykernel
label = mylabel
append = "myoptions"
</PRE>... whereas SYSLINUX uses the syntax: <PRE>label mylabel
kernel mykernel
append myoptions
</PRE>
<TABLE width="80%">
<TBODY>
<TR>
<TD vAlign=top><B>Notes:</B></TD>
<TD>Labels are mangled as if they were filenames, and must be unique
after mangling. For example, two labels "v2.1.30" and "v2.1.31" will
not be distinguishable under SYSLINUX, since both mangle to the same
DOS filename.
<P>The "kernel" doesn't have to be a Linux kernel; it can be a boot
sector or a <A
href="http://syslinux.zytor.com/faq.php#comboot">COMBOOT file</A>
</P></TD></TR></TBODY></TABLE>
<P><B>APPEND</B> <CODE>-</CODE>
<BLOCKQUOTE>Append nothing. APPEND with a single hyphen as argument in a
LABEL section can be used to override a global APPEND.
</BLOCKQUOTE><B>LOCALBOOT</B> <I>type</I> <FONT color=#ffc0c0>[ISOLINUX,
PXELINUX]</FONT>
<BLOCKQUOTE>On PXELINUX, specifying "LOCALBOOT 0" instead of a "KERNEL"
option means invoking this particular label will cause a local disk boot
instead of booting a kernel.
<P>The argument 0 means perform a normal boot. The argument 4 will perform
a local boot with the Universal Network Driver Interface (UNDI) driver
still resident in memory. Finally, the argument 5 will perform a local
boot with the entire PXE stack, including the UNDI driver, still resident
in memory. All other values are undefined. If you don't know what the UNDI
or PXE stacks are, don't worry -- you don't want them, just specify 0.
<P>On ISOLINUX, the "type" specifies the local drive number to boot from;
0x00 is the primary floppy drive and 0x80 is the primary hard drive. The
special value -1 causes ISOLINUX to report failure to the BIOS, which, on
recent BIOSes, should mean that the next boot device in the boot sequence
should be activated. </P></BLOCKQUOTE></BLOCKQUOTE><B>IMPLICIT</B>
<I>flag_val</I>
<BLOCKQUOTE>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.
</BLOCKQUOTE><B>TIMEOUT</B> <I>timeout</I>
<BLOCKQUOTE>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.
<P>NOTE: The maximum possible timeout value is 35996; corresponding to just
below one hour. </P></BLOCKQUOTE><A name=CMD_SERIAL><B>SERIAL</B> <I>port
[baudrate]</I></A>
<BLOCKQUOTE>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.
<P>For this directive to be guaranteed to work properly, it should be the
first directive in the configuration file. </P></BLOCKQUOTE><B>FONT</B>
<I>filename</I>
<BLOCKQUOTE>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 on others. </BLOCKQUOTE><B>KBDMAP</B>
<I>keymap</I>
<BLOCKQUOTE>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.)
<P>The included program keytab-lilo.pl from the LILO distribution can be
used to create such keymaps. The file keytab-lilo.doc contains the
documentation for this program. </P></BLOCKQUOTE><B>DISPLAY</B>
<I>filename</I>
<BLOCKQUOTE>Displays the indicated file on the screen at boot time (before
the boot: prompt, if displayed). This option takes the place of the
LINUXMSG.TXT and BOOTMSG.TXT files in SYSLINUX 1.0. Please see the section
below on DISPLAY files.
<P>NOTE: If the file is missing, this option is simply ignored.
</P></BLOCKQUOTE><B>PROMPT</B> <I>flag_val</I>
<BLOCKQUOTE>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. This option
takes the place of testing for the LINUXMSG.TXT file in SYSLINUX 1.0.
</BLOCKQUOTE><B>F1</B> <I>filename</I><BR><B>F2</B>
<I>filename</I><BR>&nbsp;&nbsp;<I>...etc...</I><BR><B>F9</B>
<I>filename</I><BR><B>F0</B> <I>filename</I>
<BLOCKQUOTE>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 options.) Note that F10 MUST be
entered in the config file as "F0", not "F10", and that there is currently
no way to bind file names to F11 and F12. Please see the section below on
DISPLAY files.
<P>When using the serial console, press &lt;Ctrl-F&gt;&lt;digit&gt; to get
to the help screens, e.g. &lt;Ctrl-F&gt;&lt;2&gt; to get to the F2 screen,
and &lt;Ctrl-F&gt;&lt;0&gt; for the F10 one. </P></BLOCKQUOTE>In the
configuration file blank lines and comment lines beginning with a hash mark
(#) are ignored.
<P>Note that the configuration file is not completely decoded. Syntax
different from the one described above may still work correctly in this
version of SYSLINUX, but may break in a future one. </P></BLOCKQUOTE><A
name=large><B><FONT size=+1>{ Can SYSLINUX Handle Large Kernels?
}</FONT></B></A>
<BLOCKQUOTE>This version of SYSLINUX supports large kernels (bzImage format),
eliminating the 500K size limit of the zImage kernel format. bzImage format
kernels are detected automatically and handled transparently to the user.
<P>This version of SYSLINUX also supports a boot-time-loaded ramdisk (initrd).
An initrd is loaded from a DOS file if the option "initrd=filename" (where
filename is the filename of the initrd image; the file must be located in the
root directory on the boot floppy) is present on the processed command line
(after APPEND's have been added, etc.). If several initrd options are present,
the last one has precedence; this permits user-entered options to override a
config file APPEND. Specifying "initrd=" without a filename inhibits initrd
loading. The file specified by the initrd= option will typically be a gzipped
filesystem image.
<P>NOTE: One of the main advantages with SYSLINUX is that it makes it very
easy to support users with new or unexpected configurations, especially in a
distribution setting. If initrd is used to extensively modularize the
distribution kernel, it is strongly recommended that a simple way of adding
drivers to the boot floppy be provided. The suggested manner is to let the
initrd system mount the boot floppy and look for additional drivers in a
predetermined location.
<P>To bzImage and recent zImage kernels, SYSLINUX 1.30 and higher will
identify using the ID byte 0x31. PXELINUX identifies using the ID byte 0x32,
and ISOLINUX 0x33. The ID range 0x34-0x3f is reserved for future versions of
derivatives of SYSLINUX. </P></BLOCKQUOTE><A name=format><B><FONT size=+1>{ What
is the DISPLAY File Format? }</FONT></B></A>
<BLOCKQUOTE>DISPLAY and function-key help files are text files in either DOS
or UNIX format (with or without &lt;CR&gt;). In addition, the following
special codes are interpreted:
<P>
<TABLE width="80%" border=0>
<TBODY>
<TR>
<TD><B>&lt;FF&gt;</B></TD>
<TD align=right>&lt;FF&gt; = &lt;Ctrl-L&gt; = ASCII 12</TD></TR>
<TR>
<TD></TD>
<TD>Clear the screen, home the cursor. Note that the screen is filled
with the current display color. </TD></TR>
<TR>
<TD colSpan=2>&nbsp; </TD></TR>
<TR>
<TD><B>&lt;SI&gt;</B>&lt;bg&gt;&lt;fg&gt;</TD>
<TD align=right>&lt;SI&gt; = &lt;Ctrl-O&gt; = ASCII 15</TD></TR>
<TR>
<TD></TD>
<TD>Set the display colors to the specified background and foreground
colors, where &lt;bg&gt; and &lt;fg&gt; are hex digits, corresponding to
the standard PC display attributes <PRE>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
</PRE>Picking a bright color (8-f) for the background results in the
corresponding dark color (0-7), with the foreground flashing.
<P>Colors are not visible over the serial console. </P></TD></TR>
<TR>
<TD colSpan=2>&nbsp; </TD></TR>
<TR>
<TD><B>&lt;CAN&gt;</B><VAR>filename</VAR><B>&lt;newline&gt;</B></TD>
<TD align=right>&lt;CAN&gt; = &lt;Ctrl-X&gt; = ASCII 24</TD></TR>
<TR>
<TD></TD>
<TD>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.
<P>The image is displayed in 640x480 16-color mode. Once in graphics
mode, the display attributes (set by &lt;SI&gt; 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 indicies.
<P>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. </P></TD></TR>
<TR>
<TD colSpan=2>&nbsp; </TD></TR>
<TR>
<TD><B>&lt;EM&gt;</B></TD>
<TD align=right>&lt;EM&gt; = &lt;Ctrl-Y&gt; = ASCII 25</TD></TR>
<TR>
<TD></TD>
<TD>If we are currently in graphics mode, return to text mode. </TD></TR>
<TR>
<TD colSpan=2>&nbsp; </TD></TR>
<TR>
<TD><B>&lt;DLE&gt;..&lt;ETB&gt;</B></TD>
<TD align=right>&lt;Ctrl-P&gt;..&lt;Ctrl-W&gt; = ASCII 16-23</TD></TR>
<TR>
<TD></TD>
<TD>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: <PRE>Character Text Graph Serial
------------------------------------------------------
&lt;DLE&gt; = &lt;Ctrl-P&gt; = ASCII 16 No No No
&lt;DC1&gt; = &lt;Ctrl-Q&gt; = ASCII 17 Yes No No
&lt;DC2&gt; = &lt;Ctrl-R&gt; = ASCII 18 No Yes No
&lt;DC3&gt; = &lt;Ctrl-S&gt; = ASCII 19 Yes Yes No
&lt;DC4&gt; = &lt;Ctrl-T&gt; = ASCII 20 No No Yes
&lt;NAK&gt; = &lt;Ctrl-U&gt; = ASCII 21 Yes No Yes
&lt;SYN&gt; = &lt;Ctrl-V&gt; = ASCII 22 No Yes Yes
&lt;ETB&gt; = &lt;Ctrl-W&gt; = ASCII 23 Yes Yes Yes
</PRE>For example:
<P><CODE><B>&lt;DC1&gt;Text mode&lt;DC2&gt;Graphics
mode&lt;DC4&gt;Serial port&lt;ETB&gt;</B></CODE>
<P>... will actually print out which mode the console is in! </P></TD></TR>
<TR>
<TD colSpan=2>&nbsp; </TD></TR>
<TR>
<TD><B>&lt;SUB&gt;</B></TD>
<TD align=right>&lt;SUB&gt; = &lt;Ctrl-Z&gt; = ASCII 26</TD></TR>
<TR>
<TD></TD>
<TD>End of file (DOS convention). </TD></TR></TBODY></TABLE></P></BLOCKQUOTE><A
name=otherOS><B><FONT size=+1>{ Can SYSLINUX Boot Other Operating Systems?
}</FONT></B></A>
<BLOCKQUOTE>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 <A
href="http://syslinux.zytor.com/faq.php#comboot">separate section below</A>.)
<P>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 <A
href="http://syslinux.zytor.com/faq.php#comboot">COMBOOT files</A> have
reliable magic numbers, SYSLINUX will look at the file extension. The
following extensions are recognized:
<BLOCKQUOTE>
<TABLE>
<TBODY>
<TR>
<TD>none or other
<TD>Linux kernel image
<TR>
<TD><CODE>.cbt</CODE>
<TD><A href="http://syslinux.zytor.com/faq.php#comboot">COMBOOT
image</A> (not runnable from DOS)
<TR>
<TD><CODE>.bss</CODE>
<TD>Boot sector (DOS superblock will be patched in)
<TR>
<TD><CODE>.bs</CODE>
<TD>Boot sector
<TR>
<TD><CODE>.com</CODE>
<TD><A href="http://syslinux.zytor.com/faq.php#comboot">COMBOOT
image</A> (runnable from DOS) </TR></TBODY></TABLE></BLOCKQUOTE>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.
<P><FONT size=+1><B>Can I have an example?</B></FONT>
<P>Yes! Here's how you can make a SYSLINUX disk that can boot either DOS or
Linux. The example assumes that the drive is A: in DOS and /dev/fd0 in Linux;
for other drives, substitute the appropriate drive designator.
<P><B>Method I: Using both DOS &amp; Linux to make the floppy</B>
<OL>
<LI>Make a DOS bootable disk. This can be done either by specifying the /s
option when formatting the disk in DOS, or by running the DOS command SYS
(this can be done under DOSEMU if DOSEMU has direct device access to the
relevant drive):
<BLOCKQUOTE><CODE><B>format a: /s</B></CODE> </BLOCKQUOTE><I>or</I>
<BLOCKQUOTE><CODE><B>sys a:</B></CODE> </BLOCKQUOTE>
<LI>Boot Linux. Copy the DOS boot sector from the disk into a file:
<BLOCKQUOTE><CODE><B>dd if=/dev/fd0 of=dos.bss bs=512 count=1</B></CODE>
</BLOCKQUOTE>
<LI>Run SYSLINUX on the disk:
<BLOCKQUOTE>[<CODE><B>lock a:</B></CODE> if you're running under
Win95/98/ME]<BR><CODE><B>syslinux /dev/fd0</B></CODE> </BLOCKQUOTE>
<LI>Mount the disk and copy the DOS boot sector file to it. The file *must*
have extension .bss:
<BLOCKQUOTE><CODE><B>mount -t msdos /dev/fd0 /mnt<BR>cp dos.bss /mnt
</B></CODE></BLOCKQUOTE>
<LI>Copy the Linux kernel image(s), initrd(s), etc to the disk, and
create/edit syslinux.cfg and help files if desired:
<BLOCKQUOTE><CODE><B>cp vmlinux /mnt<BR>cp initrd.gz /mnt
</B></CODE></BLOCKQUOTE>
<LI>Unmount the disk (if applicable.)
<BLOCKQUOTE><CODE><B>umount /mnt </B></CODE></BLOCKQUOTE></LI></OL><B>Method
II: Using only DOS to make the floppy</B>
<P>To make this installation in DOS only, you need the utility copybs.com
(included with SYSLINUX) as well as the syslinux.com installer.
<OL>
<LI>Make a DOS bootable disk. This can be done either by specifying the /s
option when formatting the disk in DOS, or by running the DOS command SYS:
<BLOCKQUOTE><CODE><B>format a: /s </B></CODE></BLOCKQUOTE>or
<BLOCKQUOTE><CODE><B>sys a: </B></CODE></BLOCKQUOTE>
<LI>Copy the DOS boot sector from the disk into a file. The file *must* have
extension .bss:
<BLOCKQUOTE><CODE><B>copybs a: a:dos.bss </B></CODE></BLOCKQUOTE>
<LI>Run SYSLINUX on the disk:
<BLOCKQUOTE><CODE><B>syslinux a: </B></CODE></BLOCKQUOTE>
<LI>Copy the Linux kernel image(s), initrd(s), etc to the disk, and
create/edit syslinux.cfg and help files if desired:
<BLOCKQUOTE><CODE><B>copy vmlinux a:<BR>copy initrd.gz a:
</B></CODE></BLOCKQUOTE></LI></OL></BLOCKQUOTE><A name=comboot><B><FONT
size=+1>{ What Are COMBOOT Files? }</FONT></B></A>
<BLOCKQUOTE>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:
<UL>
<LI>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.
<P></P>
<LI>Only the following fields in the PSP are supported:
<UL>
<LI>pspInt20 at offset 00h
<LI>pspNextParagraph at offset 02h;
<LI>pspCommandTail at offset 80h (contains the arguments from the SYSLINUX
command line). </LI></UL>
<P>All other fields will contain zero.
<P></P>
<LI>The program must not modify any main memory outside its 64K segment if
it returns to SYSLINUX via INT 20h. </LI></UL>SYSLINUX requires that COMBOOT
files end in ".COM" or ".CBT". Files ending in .COM can be run from the DOS
command line, files ending in .CBT cannot, otherwise there is no difference.
SYSLINUX will prefer a .CBT file over a similarly named .COM.
<P>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. </P></BLOCKQUOTE><A name=novice><B><FONT size=+1>{ What Protections Exist
In SYSLINUX? }</FONT></B></A>
<BLOCKQUOTE>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 feature.
<P>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.
<P>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. </P></BLOCKQUOTE><A
name=bootCDs><B><FONT size=+1>{ Does SYSLINUX Support Bootable CDs?
}</FONT></B></A>
<BLOCKQUOTE>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 of machines:
<UL>
<LI>Use the -s (safe, slow and stupid) option to SYSLINUX.
<LI>Put the boot image as close to the beginning of the ISO 9660 filesystem
as possible. </LI></UL>A CD-ROM is so much faster than a floppy that the -s
option shouldn't matter from a speed perspective.
<P>Of course, you want to use ISOLINUX instead. See <A
href="http://syslinux.zytor.com/iso.php">isolinux.doc</A>. </P></BLOCKQUOTE><A
name=harddrive><B><FONT size=+1>{ Can I Use SYSLINUX on a Hard Drive?
}</FONT></B></A>
<BLOCKQUOTE>SYSLINUX can boot from a FAT12 or FAT16 filesystem partition on a
hard disk (FAT32, introduced in Windows 95 OSR-2, is not supported, however.)
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.
<P>Under DOS, you can install a standard simple MBR on the primary hard disk
by running the command:
<BLOCKQUOTE><CODE><B>FDISK /MBR </B></CODE></BLOCKQUOTE>Then use the FDISK
command to mark the appropriate partition active.
<P>A simple MBR, roughly on par with the one installed by DOS (but
unencumbered), is included in the SYSLINUX distribution </P></BLOCKQUOTE><A
name=bugs><B><FONT size=+1>{ What Bugs are Still in SYSLINUX? }</FONT></B></A>
<BLOCKQUOTE>SYSLINUX is unsafe to use on any filesystem that extends past
cylinder 1024. This is a fundamental limitation of the standard BIOS API.
<P>SYSLINUX will not work (and will refuse to install) on filesystems with a
cluster size of more than 16K (typically means a filesystem of more than 1
GB.) </P></BLOCKQUOTE><A name=feedback><B><FONT size=+1>{ How Can I Give
Feedback? }</FONT></B></A>
<BLOCKQUOTE>I would 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.
<P>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 the problems.
<P>There is a mailing list for discussion among SYSLINUX users and for
announcements of new and test versions. To join, please visit <A
href="http://www.zytor.com/mailman/listinfo/syslinux"><CODE>http://www.zytor.com/mailman/listinfo/syslinux</CODE></A>;
you can also examine the list archives there.
<P>Any feedback on these instructions or on the HTML formatting should be
cc:'ed to <A href="mailto:david@weekly.org">David Weekly</A>.
</P></BLOCKQUOTE></FONT></BODY></HTML>