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G.3. Kernel Options

The following kernel options can be specified in /etc/lilo.conf as well as on the boot command line:

append=string

Appends the options specified in string to the parameter line passed to the kernel. This is typically used to specify certain hardware parameters. For example, if your system has more than 64 MB of memory (i.e., more than your BIOS can recognize), you can use append:

append = "mem=128M"

initrd=filename

Specifies the file to load into /dev/initrd when booting with a RAM disk. See also the options load_ramdisk, prompt_ramdisk, ramdisk_size, and ramdisk_start.

literal=string

Is like append, but replaces all other kernel boot options.

noinitrd

Preserves the contents of /dev/initrd so they can be read once after the kernel is booted.

prompt_ramdisk=n

Specifies whether the kernel should prompt you to insert the floppy disk that contains the RAM disk image, for use during Linux installation.

Values of n are:

0

Don't prompt. Usually used for an installation where the kernel and the RAM disk image both fit on one floppy.

1

Prompt. This is the default.

ramdisk=size

Is obsolete. This option should be used only with kernels older than Version 1.3.48. For newer kernels, see the options load_ramdisk, prompt_ramdisk, ramdisk_size, and ramdisk_start.

ramdisk_size=n

Specifies the amount of memory, in kilobytes, to be allocated for the RAM disk. The default is 4096, which allocates 4 MB.

ramdisk_start=offset

Used for a Linux installation where both the kernel and the RAM disk image are on the same floppy. offset indicates the offset on the floppy where the RAM disk image begins; it is specified in kilobytes.

root=root-device

Specifies the device that should be mounted as the root. If the special name current is used, the root device is set to the device on which the root filesystem is currently mounted. This option defaults to the root-device setting contained in the kernel image.

vga=mode

Specifies the VGA text mode that should be selected when booting. mode defaults to the VGA mode setting in the kernel image. The values are not case-sensitive. They are:

ask

Prompts the user for the text mode. Pressing Enter in response to the prompt displays a list of the available modes.

extended (or ext)

Selects 80x50 text mode.

normal

Selects normal 80x25 text mode.

number

Uses the text mode that corresponds to number. A list of available modes for your video card can be obtained by booting with vga=ask and pressing Enter.



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