MKINITRD(5)							   User Manuals 						       MKINITRD(5)

NAME

       mkinitrd - description of modular scripts layout

SYNOPSIS

       (not applicable)

DESCRIPTION

       mkinitrd creates initial ramdisk images for booting Linux. It is designed to be modular, so that functionality required by other programs
       can be maintained in separate scripts.

DIRECTORY LAYOUT

       All files are located in the directory /lib/mkinitrd. The directory has the following layout:

       bin
	   External program required during boot

       dev
	   Additional devices nodes to be copied into the mkinitrd.

       scripts
	   Repository for mkinitrd scripts

       setup
	   Resolved links for scripts to be executed during creation of the initrd

       boot
	   Resolved links for scripts to be executed during boot.

SCRIPT REPOSITORY

       The directory /lib/mkinitrd/scripts is the repository for all mkinitrd scripts. They follow the naming convention

	   <type>-<name>.sh

       <type> can be either setup for scripts to be called during initrd creation or boot for scripts to be called during boot. The <name> for a
       script serves as an identification for the implemented feature; it is assumed that scripts named boot-foo.sh and setup-foo.sh both refer to
       the feature foo.

SCRIPT SYMLINK RESOLUTION

       The directories /lib/mkinitrd/setup and /lib/mkinitrd/boot hold the resolved symlinks to the scripts in the mkinitrd repository. The
       symlinks have the naming convention

	   <number>-<name>.sh

       where <number> determines the execution order (lower numbers will be executed earlier) and <name> is the names of the script as mentioned
       in the previous section. The symlinks are maintained by the program /sbin/mkinitrd_setup which evaluates the tags in the scripts and
       creates symlinks with the correct name. Manual maintenance in the /lib/mkinitrd/setup or /lib/mkinitrd/boot directories are strongly
       discouraged, as any call to /sbin/mkinitrd_setup will remove the manually created links.

SCRIPT KEYWORDS

       The execution order of the mkinitrd scripts is determined by keywords. The following keywords are recognized:

       #%stage: <name>
	   The execution stage for this script

       #%depends: <list>
	   Space-separated list of features or scripts names this script depends upon.

       #%provides: <list>
	   Space-separated list of additional features provided by this script.

       #%dontshow
	   Don't show the script in the list of features displayed to the user.

       #%programs: <list>
	   A (space separated) list of programs, specified by their full path, that should be included in the initrd.

	   NOTE: The path is the full path in the initrd, not in the system.  mkinitrd tries to discover programs automatically, which means that
	   programs in /sbin will be also searched in /usr/sbin and programs in /bin will be also searched in /usr/bin.

	   Libraries are automatically resolved by ldd(1). Please note that libraries that are loaded at runtime by dlopen(3) are not included
	   automatically. They have to be copied manually.

       #%modules: <list>
	   List of (space separated) kernel modules (only the name, no path, without suffix) that should be included in the initrd. The modules
	   must be loaded in the corresponding boot script with load_modules.

       #%udevmodules: <list>
	   List of (space separated) kernel modules (only the name, no path, without suffix) that should be included in the initrd but are loaded
	   automatically with either udev or something else (like file system modules with mount).

       Each script provides per default a feature with the script name, so that setup-foo.sh automatically provides a feature foo.

       All dependend scripts (i.e. any feature listed in the #%depends: list) will be executed prior to this script.

EXECUTION STAGES

       Script execution is gouverned by stages. The stages define the overall execution order as each stage is executed sequentially. The defined
       stages are:

       setup
	   General preparation

       filesystem
	   Filesystem detection and maintenance

       crypto
	   Handling of cryptographic volumes

       volumemanager
	   Handling of LVM2 and EVMS volumes

       softraid
	   Detection and setup of MD devices

       partitions
	   Detection and setup of partitions.

       devicemapper
	   Device-mapper devices presenting full disks, e.g. multipath and dmraid

       block
	   Detection and setup of block devices.

       device
	   Detection and setup of hardware devices

       boot
	   Final cleanups/preparation

       During setup the stages are executed from setup to boot; during boot the stages are executed in reversed order. The stages itself are
       defined corresponding to the Novell Storage Foundation Layout. This induces some restrictions to the possible device setups, as e.g. MD
       over LVM is not supported.

       The stages are executed sequentially. All scripts for a stage have to be executed before those for the next stage are evaluated. Within a
       stage scripts can run parallel where pos- sible.

       As each stage serves as a checkpoint it is not possible to have dependencies across stages. So script foo in stage filesystem cannot depend
       on script bar in stage block.

SCRIPT INSTALLATION

       New scripts should be copied to /lib/mkinitrd/scripts and the appropriate keywords should be inserted. Afterwards /sbin/mkinitrd_setup
       should be executed to update the symlinks in boot and setup.

       For removal the scripts should be deleted and /sbin/mkinitrd_setup should be called to update the symlinks.

AUTHORS

       Steffen Winterfeldt <snwint@suse.de>, Susanne Oberhauser <froh@suse.de>, Andreas Grunbacher <agruen@suse.de>, Hannes Reinecke
       <hare@suse.de>, Alexander Graf <agraf@suse.de>, Bernhard Walle <bwalle@suse.de>

FILES

       /lib/mkinitrd /sbin/mkinitrd /sbin/mkinitrd_setup

BUGS

       Please report bugs and enhancement requests at https://bugzilla.novell.com.

SEE ALSO

       mkinitrd(8), lsinitrd(8)

mkinitrd							    07/05/2010							       MKINITRD(5)