From Codtech

TIP: Kernel command line option names should always be in lowercase characters. The use of uppercase names has been DEPRECATED and will be removed in future versions.

Standard command line parameters

There's also a page about Generic information on Kernel command line

break

At some specific points in the startup sequence the function maybe_break is called, and if the parameter to this function matches the one passed in the kernel command line a shell is spawned.

Possible values

Example

... break=mount ...

cryptopts

[...]

debug

[...]

init

The name of the init command

Possible values

• /sbin/init   default  
• path

ip

ip is then stored into IPOPTS and in some (if not all) of the cases this value is used by ipconfig#interface spec long form.

Possible values

• (empty)   default  
• <client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
• off

Comments

IPAPPEND flag_val [PXELINUX only]

The IPAPPEND option is available only on PXELINUX. The flag_val is an OR of the following options:

1: indicates that an option of the following format should be generated and added to the kernel command line:

 ip=<client-ip>:<boot-server-ip>:<gw-ip>:<netmask>

... based on the input from the DHCP/BOOTP or PXE boot server.

The use of this option is not recommended. If you have to use it, it is probably an indication that your network configuration is broken. Using just ip=dhcp on the kernel command line is a preferrable option, or, better yet, run dhcpcd/dhclient, from an initrd if necessary.

netboot

[...]

noresume

Disables resume and restores original swap space.

quiet

Disable log messages.

nfsroot

nfs root filesystem for disk-less boxes. See Documentation/nfsroot.txt in kernel documentation.

nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]

If the `nfsroot' parameter is NOT given on the command line, the default /tftpboot/%s will be used.

	port		= as given by server portmap daemon
	rsize		= 1024
	wsize		= 1024
	timeo		= 7
	retrans		= 3
	acregmin	= 3
	acregmax	= 60
	acdirmin	= 30
	acdirmax	= 60
	flags		= hard, nointr, noposix, cto, ac

ro

Mount root device read-only on boot.

root

See CULT: Kernel command line parameters#root_2

rootdelay

Delay (in seconds) to pause before attempting to mount the root filesystem.

rootflags

Set root filesystem mount option string.

rw

Mount root device read-write on boot.

vga

VGA mode.Graphical boot screen.

If you graphics controller is fully VESA compliant you can try setting the vga mode in the kernel command line, additionally giving you a graphical logo.

Boot logo

Possible values

	640x400	800x600	1024x768
256	0x301 (769)	0x303 (771)	0x305 (773)
32K	0x310 (784)	0x313 (787)	0x316 (790)
64K	0x311 (785)	0x314 (788)	0x317 (791)
16M	0x312 (786)	0x315 (789)	0x318 (792)

Module parameters

Module parameters can be specified in kernel command line as

... module.parameter=value ...

Example

... usbcore.blinkenlights=1 ...

CULT extra command line parameters

These are of CULT exclusive use. Some of these parameters are also used in the standard version of Debian/Ubuntu but the use is extended in CULT thus are listed here.

blacklist

Specifies kernel modules to blacklist. List separator must be + (plus). The content will be splitted and added to /etc/modprobe.d/blacklist.

Example

... blacklist=mod1+mod2 ...

boot

Specifies the boot method.

Possible values

Example

... boot=initrd ...

cult_conf_url

Remote configuration URL.

TIP: This is useful when the DHCP server is not configurable and there's no other option to specify the configuration URL

Possible values

...

Example

 ... cult_conf_url=http://confserver/cult/conf/${MAC} ...

Since

3.1

cult_debug

Enable debug.

Possible values

0   default  

Integer

Example

... cult_debug=1 ...

dhcp_timeout

Specify the DHCP timeout. This value is used by ipconfig.

Possible values

30   default  

Integer

Since

3.1-3

gmode

Grpahical mode. Specifying

 ... gmode=widthxheight[xdepth[xfreq]][@rotation] ...

will use a screen of the specified width, height, screen depth, frequency, and rotation (0, 90, 180 and 270 are legal values).

Posible values

• 800x600x24   default  
• XxY[xBITS[xFREQ]][@ROT]

TIP: Xvesa will only accept standard VESA 2.0 display timings (60Hz refresh rate).

Example

... gmode=1024x768x24 ...

lang

Language. Specifying

 ... lang=en ...

will use this language as the default language.

Possible values

• en   default  
• es
• ...

Since

3.1-3

mouse

Mouse device and buttons

Possible values

• /dev/mouse,5   default  
• mousedevice,mousebuttons

Example

... mouse=/dev/mouse,5 ...

rdp

Parameters for the rdesktop command line.

Spaces must be encoded as +.

Example

... rdp=-a+16+-k+es+192.168.107.228 ...

root

The root filesystem to use.

Possible values

The name of the root filesystem, can also be specified by LABEL or UUID. These options are useful when using AoE because is somewhat difficult to determine the AoE shelf and slot in advance.

The special value /dev/nfs is necessary to enable the pseudo-NFS-device. Note that it's not a real device but just a synonym to tell the kernel to use NFS instead of a real device with #nfsroot.

Example

... root=UUID=b057271a-6fb4-4ef2-af8c-50eb006948eb

rootfstype

The root filesystem type

session

The session name to run. See CULT: launcher.sh in CULT virtual manager and CULT classic standard.

In CULT classic custom this value is passed to /scripts/session script as a parameter in init.

Possible values

• vm   default  
• rdp
• run-vm-session (same as vm)
• run-rdp-session (same as rdp)
• xdm (CULT classic custom only)
• any other value as logn as run-value-session is defined

session_params

Command line parameters to #session in CULT: launcher.sh

splash

Show usplash splash creen.

see also #vga.

xdm

Parameters for the command line when SESSION is xdm.

Spaces must be encoded as +.

Possible values

• -broadcast   default  
• -query+server
• -indirect+server

Example

... xdm=-query+192.168.1.100 ...