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.
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.
Information on many boot parameters can be found in the
BootPrompt HOWTO, including tips for obscure hardware. This
section contains only a sketch of the most salient parameters. Some
common gotchas are included below in
When the kernel boots, a message
should be emitted early in the process.
total should match the total amount of RAM,
in kilobytes. If this doesn't match the actual amount of RAM you have
installed, you need to use the
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.
If you are booting with a serial console, generally the kernel will
(although not on DECstations)
If you have a videocard (framebuffer) and a keyboard also attached to
the computer which you wish to boot via serial console, you may have
to pass the
argument to the kernel, where device is
your serial device, which is usually something like
For &arch-title; the serial devices are ttya or
Alternatively, set the input-device and
output-device OpenPROM variables to
Debian Installer Arguments
The installation system recognizes a few boot arguments which may be
These parameter settings will similarly set the highest priority of
messages to be displayed.
With DEBCONF_PRIORITY=critical, the
installation system will display only critical messages and try to do
the right thing without fuss. If problems are encountered, the
installer adjusts the priority as needed.
If DEBCONF_PRIORITY=high (the default setting),
both high and critical priority messages are shown, but medium and low
priority messages are skipped. When
DEBCONF_PRIORITY=low is used, all messages are
This boot parameter controls the type of user interface used for the
installer. The current possible parameter settings are:
The default front end is DEBCONF_FRONTEND=newt.
may be preferable for serial console installs.
Passing this boot parameter will cause the boot to be more verbosely
This is the default.
More verbose than usual.
Lots of debugging information.
Shells are run at various points in the boot process to allow detailed
debugging. Exit the shell to continue the boot.
The value of the parameter is the path to the device to load the
Debian installer from. For example,
The boot floppy, which normally scans all floppys and USB storage
devices it can to find the root floppy, can be overridden by this
parameter to only look at the one device.
Some architectures use the kernel framebuffer to offer installation in
a number of languages. If framebuffer causes a problem on your system
you can use this option to disable the feature. Problem symptoms are
error messages about bterm or bogl, a blank screen, or a freeze within
a few minutes after starting the install.
The video=vga16:off argument may also be used
to disable the framebuffer. Such problems have been reported on a Dell
Inspiron with Mobile Radeon card.
Such problems have been reported on the Amiga 1200 and SE/30.
Such problems have been reported on hppa.