MKINITRD(8)							   MKINITRD(8)



NAME
       mkinitrd - make an initrd image


SYNOPSIS
       mkinitrd [-k] [-d confdir] [-m command] -o outfile [-r root] [version]

       mkinitrd  [--supported-host-version= hversion] [--supported-target-ver
       sion= tversion]


DESCRIPTION
       The mkinitrd script constructs a directory structure that can serve  as
       an initrd root file system.  It then generates an image containing that
       directory structure using mkcramfs(8), which can be  loaded  using  the
       initrd  mechanism.  The kernel modules for the specified kernel version
       will be placed in the directory structure.  If version is  omitted,  it
       defaults to the version of the kernel that is currently running.



       The second syntax returns 0 if mkinitrd can create a ramdisk running on
       a kernel of the given host version ( hversion ) and for a kernel of the
       given target version ( tversions ), and 2 otherwise.



       The  directory  structure  can  be  customised  by placing scripts into
       confdir/scripts.  They will be run using run-parts(8) just  before  the
       directory   is	fed   to   mkcramfs(8).    If  there  are  scripts  in
       /usr/share/initrd-tools/scripts, they will be run prior to the  scripts
       in confdir.



       You  can  also  specify modules to load by putting them in confdir/mod
       ules, whose format is identical	to  that  of  /etc/modules,  which  is
       described in modules(5).

       When the system boots using an initrd image created by mkinitrd(8), the
       linuxrc will wait for an amount of time	which  is  configured  through
       mkinitrd.conf(5), during which it may be interrupted by pressing ENTER.
       After that, the modules specified in confdir/modules (and possibly oth
       ers if ROOT is not null) will be loaded, followed by any actions gener
       ated when ROOT is not null.  Finally  any  scripts  or  executables  in
       /scripts will be run in alphabetical order.

       If  the directory /lib/modules/version/initrd exists, the modules in it
       will be included on the initrd image.  They  will  be  loaded  at  boot
       time.


OPTIONS
       -d confdir
	      By  default  mkinitrd  looks  for  its  configuration  files  in
	      /etc/mkinitrd.  Use this option to override that.


       -k     Do not delete the  temporary  working  directory	that  mkinitrd
	      uses.  This is useful for debugging.


       -m command
	      This option overrides the setting of MKIMAGE in mkinitrd.conf.


       -o outfile
	      This option causes mkinitrd to write the image to outfile.


       -r root
	      This option overrides the setting of ROOT in mkinitrd.conf.


       --supported-host-version=hversion
	      This option queries if mkinitrd can create ramdisks on a running
	      kernel of version hversion.


       --supported-target-version=tversion
	      This option queries if mkinitrd can create ramdisks  for	kernel
	      version tversion.


FILES
       /etc/mkinitrd/exe
	      This  file contains full paths to shared executables that should
	      be included in the initrd image.	mkinitrd will include them  as
	      well as any shared libraries that they are linked with.


       /etc/mkinitrd/files
	      This  file  contains full paths to files that should be included
	      in the initrd image.


       /etc/mkinitrd/mkinitrd.conf
	      The default configuration file for the script.


       /etc/mkinitrd/modules
	      All modules specified in this file will be loaded when the  sys
	      tem  boots  using  the  generated  image.  However, they are not
	      automatically included on the image.  You will  either  have  to
	      use  the	appropriate  MODULES  setting, or copy them in using a
	      script in /etc/mkinitrd/scripts.


       /etc/mkinitrd/scripts
	      Scripts in this directory matching the run-parts(8) naming  con
	      vention  are  run just before the image is generated from.  INI
	      TRDDIR, MODULEDIR and VERSION  are  available  to  the  scripts.
	      They  contain  the  path to the initrd directory structure under
	      construction, the value of /lib/modules/version, and  the  value
	      of version respectively.


       /etc/mkinitrd/DSDT
	      If  this file exists, it will be appended to the initrd in a way
	      that causes it to be loaded by ACPI.


NOTES
       By default mkinitrd will generate a CRAMFS image.  You can generate  an
       initrd  image of another type by changing the MKIMAGE setting in mkini
       trd.conf.



       If both mdadm(8) and raidtools2 are installed, the former is preferred.
       At  the moment, mkinitrd uses the -D option of mdadm(8) to discover the
       constituent devices.  This means that only devices that are part of the
       array  at  the  time  that mkinitrd is run will be used later on.  This
       problem does not exist when raidtools2 is used.



       Because lvm10 and lvm2 cannot coexist currently, we do not support gen
       erating	an  initrd  image  for lvm10 while the system is running lvm2.
       The converse is supported.



       Shell scripts may be placed in /usr/share/initrd-tools/probe.d  to  add
       new  methods  for  probing root devices.  These scripts will be sourced
       when mkinitrd runs.  They should define a shell function  that  assigns
       the  value 1 to the variable ok if and only if it is able to handle the
       device given to it.  The function will be called  with  the  major  and
       minor  numbers  of  the device in decimal form.	The script should call
       the function register_probe with the  name  of  that  function.	 These
       scripts	must  defer  any  real	work  to scripts in /usr/share/initrd-
       tools/scripts so that they do not interfere with mkinitrd itself.


SEE ALSO
       mkcramfs(8), mkinitrd.conf(5), run-parts(8)


AUTHOR
       Herbert Xu 



Initrd Tools		 $Date: 2004/04/08 11:27:00 $		   MKINITRD(8)