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Hans de Goede 3508cc816e Add fcoe booting support
Supported cmdline formats:
fcoe=<networkdevice>:<dcb|nodcb>
fcoe=<macaddress>:<dcb|nodcb>

Note currently only nodcb is supported, the dcb option is reserved for
future use.

Note letters in the macaddress must be lowercase!

Examples:
fcoe=eth0:nodcb
fcoe=4A:3F:4C:04:F8:D7:nodcb
2009-08-28 12:53:56 +02:00
modules.d Add fcoe booting support 2009-08-28 12:53:56 +02:00
test TEST-10-RAID: new mdadm is picky about partitions 2009-08-14 17:27:50 +02:00
.gitignore do not ignore old test files 2009-05-25 15:33:19 +02:00
AUTHORS mv Authors AUTHORS, add AUTHORS to specfile 2009-06-19 14:40:09 +02:00
COPYING And licensing... 2008-12-10 16:36:31 -05:00
HACKING add more documentation 2009-06-17 15:43:53 +02:00
Makefile Makefile: add hostimage target for a hostonly image 2009-08-19 17:10:38 +02:00
NEWS version 0.9 2009-08-14 17:59:43 +02:00
README Some updates to the README files 2009-08-20 14:14:21 -05:00
README.generic Some updates to the README files 2009-08-20 14:14:21 -05:00
README.kernel dracut: add --kernel-only and --no-kernel arguments 2009-07-22 15:07:11 +02:00
README.modules Some updates to the README files 2009-08-20 14:14:21 -05:00
TODO add more documentation 2009-06-17 15:43:53 +02:00
dracut Split kernel module loading into smaller chunks. 2009-08-16 15:28:45 -05:00
dracut-catimages Update dracut-catimages to make it much more robust in the face of 2009-08-14 22:51:25 -05:00
dracut-functions should_source_module(): refined check 2009-08-27 12:53:38 +02:00
dracut-gencmdline Split kernel module loading into smaller chunks. 2009-08-16 15:28:45 -05:00
dracut.8 dracut.8: document rootfstype and rootflags 2009-08-28 12:53:03 +02:00
dracut.conf add sample dracut.conf file 2009-06-04 13:07:59 +02:00
dracut.spec dracut.spec add NEWS to dracut and dracut-tools 2009-08-14 18:03:33 +02:00
switch_root.c switch_root: add subroot support 2009-07-14 13:53:44 +02:00

README

Dracut
------
Dracut is a new initramfs infrastructure.

Information about the initial goals and aims can be found at 
https://fedoraproject.org/wiki/Initrdrewrite 

Unlike existing initramfs's, this is an attempt at having as little as
possible hard-coded into the initramfs as possible.  The initramfs has
(basically) one purpose in life -- getting the rootfs mounted so that
we can transition to the real rootfs.  This is all driven off of
device availability.  Therefore, instead of scripts hard-coded to do
various things, we depend on udev to create device nodes for us and
then when we have the rootfs's device node, we mount and carry on.
This helps to keep the time required in the initramfs as little as
possible so that things like a 5 second boot aren't made impossible as
a result of the very existence of an initramfs.  It's likely that
we'll grow some hooks for running arbitrary commands in the flow of
the script, but it's worth trying to resist the urge as much as we can
as hooks are guaranteed to be the path to slow-down.

Most of the initrd generation functionality in dracut is provided by a bunch
of generator modules that are sourced by the main dracut script to install
specific functionality into the initrd.  They live in the modules.d 
subdirectory, and use functionality provided by dracut-functions to do their 
work.

Some general rules for writing modules:
 * Use one of the inst family of functions to actually install files
   on to the initrd.  They handle mangling the pathnames and (for binaries,
   scripts, and kernel modules) installing dependencies as appropriate so
   you do not have to.
 * Scripts that end up on the initrd should be POSIX compliant. dracut
   will try to use /bin/dash as /bin/sh for the initrd if it is available,
   so you should install it on your system -- dash aims for strict POSIX
   compliance to the extent possible.
 * Hooks MUST be POSIX compliant -- they are sourced by the init script,
   and having a bashism break your user's ability to boot really sucks.
 * Generator modules should have a two digit numeric prefix -- they run in
   ascending sort order. Anything in the 90-99 range is stuff that dracut
   relies on, so try not to break those hooks.
 * Hooks must have a .sh extension.
 * Generator modules are described in more detail in README.modules.
 * We have some breakpoints for debugging your hooks.  If you pass 'rdbreak'
   as a kernel parameter, the initramfs will drop to a shell just before
   switching to a new root. You can pass 'rdbreak=hookpoint', and the initramfs
   will break just before hooks in that hookpoint run. 

Also, there is an attempt to keep things as distribution-agnostic as
possible.  Every distribution has their own tool here and it's not
something which is really interesting to have separate across them.
So contributions to help decrease the distro-dependencies are welcome.

Currently dracut lives on sourceforge.

Project Page:
https://sourceforge.net/projects/dracut/

Drop Harald Hoyer <harald@redhat.com> a mail, if you want to help with 
the documentation, git access, etc.

Git Repository:
http://dracut.git.sourceforge.net/
git://dracut.git.sourceforge.net/gitroot/dracut/dracut

Trac Instance:
http://apps.sourceforge.net/trac/dracut/ 

The git tree can be found at
git://dracut.git.sourceforge.net/gitroot/dracut/dracut for now.  See the TODO
file for things which still need to be done and HACKING for some
instructions on how to get started.  There is also a mailing list that
is being used for the discussion -- initramfs@vger.kernel.org.  It is
a typical vger list, send mail to majordomo@vger.kernel.org with body
of 'subscribe initramfs email@host.com' 


Licensed under the GPLv2