fedora 12 dracut

8/7/2019 Fedora 12 Dracut

1/22

Fedora 12 Dracut

Fedora 12 DracutFinnbarr P. Murphy

([email protected])

Fedora 12 (Constantine) contains a new infrastructure for populating and building an initramfs

image called Dracut. Dracut is a replacement for both the mkinitrd build script and the nash script

interpreter. The project was started by Jeremy Katz when he worked at Redhat as a result of

discussions at a Linux Summit a couple of years ago and some community prodding by David Jones.

Currently Harald Hoyer, who works for Redhat, is the owner of the project. In this post I examine

Dracut in detail and show the major differences between the existing and new infrastructures.

I assume that if you are reading this post you are somewhat familiar with how Linux (and Fedora

in particular) is booted, the purpose ofinitrd, initramfs and mkinitrd. Dracut continues to use the

initramfs architecture but replaces the /sbin/mkinitrd shell script with its own shell script

/sbin/dracut, the nash script interpreter with dash (Debian Almquist shell) if available otherwisebash, and a totally new init script.

First let us look at the changes that are or may be visible when you boot your system. If you look

at your grub configuration file you will see a number of changes. Here is one stanza from my

current configuration file.

title Fedora (2.6.31.6-166.fc12.x86_64)

root (hd0,1)

kernel /vmlinuz-2.6.31.6-166.fc12.x86_64 ro root=UUID=434794ee-a7ff-4156-aabf-53a79c3d

319b LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us rhgb quiet

initrd /initramfs-2.6.31.6-166.fc12.x86_64.img

The number of arguments on the kernel command line has increased. Now a console language

(locale), a console font and keyboard type and table are specified. Console fonts are used to

display text (glyphs) on a Linux console. Numerous console fonts are available; they are kept in

/lib/kbd/consolefonts. The Unicode console font latarcyrheb-sun16 covers Latin, Cyrillic, Hebrew

and Arabic. This is the default Fedora console font. Where specified on the kernel command line,

I18N-related parameters will be written to the appropriate file in the initramfs. For example,

KEYTABLE=us wil l be written to the initramfss /etc/sysconfig/keyboard,

SYSFONT=latarcyrheb-sun16 will be written to the initramfss /etc/sysconfig/i18n, and so on.

Numerous other kernel command line options are also supported. These are all documented in thedracut(8) man page. Support for debugging initramfs problems has been significantly improved.

Here is a list of the documented debugging options:

rdinfo print informational output though quiet is setq

rdshell allow dropping to a shell, if root mounting failsq

rdinitdebug set -x for the dracut shell and logs to dmesg, console and /init.logq

rdbreak drop to a shell at the endq

rdbreak={cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount|pre-pivot} drop to a shellq

on defined breakpoint

rdudevinfo set udev to loglevel infoq

rdudevdebug set udev to loglevel debugq

rdnetdebug debug network scripts in dracut. Output is written to /tmp/q

The one that I particularly like is the ability to drop into a shell on a defined breakpoint.

03-03-2011 Copyright 2004-2011 Finnbarr P. Murphy. All rights reserved. 1/22
http://blog.fpmurphy.com/2009/11/fedora-12-dracut.htmlhttp://fedoraproject.org/wiki/Features/Dracuthttps://fedoraproject.org/wiki/Initrdrewritehttp://www.harald-hoyer.de/http://en.wikipedia.org/wiki/Initrdhttp://www.kernel.org/doc/Documentation/filesystems/ramfs-rootfs-initramfs.txthttp://en.wikipedia.org/wiki/Debian_Almquist_shellhttp://en.wikipedia.org/wiki/Debian_Almquist_shellhttp://www.kernel.org/doc/Documentation/filesystems/ramfs-rootfs-initramfs.txthttp://en.wikipedia.org/wiki/Initrdhttp://www.harald-hoyer.de/https://fedoraproject.org/wiki/Initrdrewritehttp://fedoraproject.org/wiki/Features/Dracuthttp://blog.fpmurphy.com/2009/11/fedora-12-dracut.html


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Fedora 12 Dracut

dracut: + read line

dracut: + [ -e /pre-trigger/30parse-dm.sh ]

dracut: + . /pre-trigger/30parse-dm.sh

dracut: + getarg rd_NO_DM

dracut: + set +x

dracut: + return 1

dracut: + getarg nodmraid

dracut: + set +x

dracut: + return 1dracut: + [ -e /pre-trigger/30parse-md.sh ]

dracut: + . /pre-trigger/30parse-md.sh

dracut: + getarg rd_NO_MD

dracut: + set +x

dracut: + return 1

dracut: + getargs rd_MD_UUID=

dracut: + set +x

dracut: + return 1

dracut: + MD_UUID=

dracut: + [ -n ]

dracut: + [ -e /etc/mdadm.conf ]

dracut: + getarg rd_NO_MDIMSM

dracut: + set +x

dracut: + return 1dracut: + getarg noiswmd

dracut: + set +x

dracut: + return 1

dracut: + getarg nodmraid

dracut: + set +x

dracut: + return 1

dracut: + udevadm trigger

dracut: + getarg rdbreak=initqueue

dracut: + set +x

dracut: + return 1

dracut: + i=0

dracut: + :

dracut: + check_finished

dracut: + local fdracut: + [ -e /initqueue-finished/block.sh ]

dracut: + . /initqueue-finished/block.sh

dracut: + [ -e /dev/root ]

dracut: + return 1

dracut: + udevsettle

dracut: + [ -z 145 ]

dracut: + [ 145 -ge 143 ]

dracut: + udevadm settle --exit-if-exists=/initqueue/work


dracut: + local f

dracut: + [ -e /initqueue-finished/block.sh ]



dracut: + return 1dracut: + [ -f /initqueue/work ]

dracut: + [ -e /initqueue/*.sh ]

dracut: + break

dracut: + udevadm settle --timeout=0

dracut: + modprobe scsi_wait_scan

dracut: WARNING: Deprecated config file /etc/modprobe.conf, all config files belong into /

etc/modprobe.d/.

dracut: + rmmod scsi_wait_scan


dracut: + [ -e /initqueue-settled/blocksymlink.sh ]

dracut: + job=/initqueue-settled/blocksymlink.sh . /initqueue-settled/blocksymlink.sh

dracut: + [ -e /dev/disk/by-uuid/434794ee-a7ff-4156-aabf-53a79c3d319b ]


dracut: + local fdracut: + [ -e /initqueue-finished/block.sh ]





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Fedora 12 Dracut

dracut: + return 1

dracut: + [ -e /initqueue-settled/lvm_scan.sh ]

dracut: + job=/initqueue-settled/lvm_scan.sh . /initqueue-settled/lvm_scan.sh

dracut: + [ -e /initqueue-settled/lvm_scan.sh ]

dracut: + rm /initqueue-settled/lvm_scan.sh

dracut: + /sbin/lvm_scan

dracut: + getargs rd_LVM_VG=

dracut: + set +x

dracut: + return 1dracut: + VGS=

dracut: + [ -d /etc/lvm ]

dracut: + [ -e /tmp/.lvm_scan-sda3 ]

dracut: + echo -n sda3

dracut: + lvmdevs=sda3

dracut: + [ ! -e /etc/lvm/lvm.conf ]

dracut: + info Scanning devices sda3 for LVM volume groups

dracut: + [ -z ]

dracut: + DRACUT_QUIET=no

dracut: + getarg quiet

dracut: + set +x

dracut: + return 1

dracut: + echo dracut: Scanning devices sda3 for LVM volume groups

dracut: + [ yes != yes ]dracut: + lvm vgscan

dracut: + vinfo

dracut: + read line

dracut: + info Reading all physical volumes. This may take a while...

dracut: + [ -z yes ]

dracut: + echo dracut: Reading all physical volumes. This may take a while...

dracut: + [ yes != yes ]

dracut: + read line

dracut: + info Found volume group "vg_ultra" using metadata type lvm2


dracut: + echo dracut: Found volume group "vg_ultra" using metadata type lvm2


dracut: + read line

dracut: + lvm vgchange+ -aydracut: vinfo

dracut: + read line

dracut: + info 2 logical volume(s) in volume group "vg_ultra" now active


dracut: + echo dracut: 2 logical volume(s) in volume group "vg_ultra" now active


dracut: + read line

dracut: + [ ]

dracut: + unset lvmwritten


dracut: + local f



dracut: + [ -e /dev/root ]dracut: + return 1


dracut: + continue

dracut: + :


dracut: + local f




dracut: + return 1

dracut: + udevsettle

dracut: + [ -z 145 ]

dracut: + [ 145 -ge 143 ]

dracut: + udevadm settle --exit-if-exists=/initqueue/workdracut: + check_finished

dracut: + local f




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Fedora 12 Dracut



dracut: + return 0

dracut: + break

dracut: + unset job

dracut: + unset queuetriggered

dracut: + getarg rdbreak=pre-mount

dracut: + set +x

dracut: + return 1dracut: + source_all pre-mount

dracut: + local f

dracut: + [ pre-mount ]

dracut: + [ -d /pre-mount ]

dracut: + return

dracut: + getarg rdbreak=mount

dracut: + set +x

dracut: + return 1

dracut: + i=0

dracut: + :

dracut: + [ -d /sysroot/proc ]

dracut: + [ -f /mount/10resume.sh ]

dracut: + . /mount/10resume.sh

dracut: + [ -s /.resume -a -b ]dracut: + [ -d /sysroot/proc ]

dracut: + [ -f /mount/99mount-root.sh ]

dracut: + . /mount/99mount-root.sh

dracut: + [ -n block:/dev/disk/by-uuid/434794ee-a7ff-4156-aabf-53a79c3d319b -a -z ]

dracut: + mount -t auto -o ro /dev/disk/by-uuid/434794ee-a7ff-4156-aabf-53a79c3d319b /sysr

oot

dracut: + ROOTFS_MOUNTED=yes


dracut: + break

dracut: + i=1

dracut: + [ 1 -gt 20 ]

dracut: + :


dracut: + breakdracut: + echo -n Mounted root filesystem

dracut: + vinfo

dracut: + read line

dracut: + read dev mp rest

dracut: + [ / = /sysroot ]


dracut: + [ /proc = /sysroot ]


dracut: + [ /sys = /sysroot ]


dracut: + [ /dev = /sysroot ]


dracut: + [ /dev/pts = /sysroot ]

dracut: + read dev mp restdracut: + [ /dev/shm = /sysroot ]


dracut: + [ /sysroot = /sysroot ]

dracut: + echo /dev/dm-0

dracut: + info Mounted root filesystem /dev/dm-0


dracut: + echo dracut: Mounted root filesystem /dev/dm-0


dracut: + read line


dracut: + getarg rdbreak=pre-pivot

dracut: + set +x

dracut: + return 1

dracut: + source_all pre-pivotdracut: + local f

dracut: + [ pre-pivot ]

dracut: + [ -d /pre-pivot ]



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Fedora 12 Dracut

dracut: + [ -e /pre-pivot/30crypt-cleanup.sh ]

dracut: + . /pre-pivot/30crypt-cleanup.sh

dracut: + cryptsetup luksClose /dev/mapper/luks-*

dracut: + [ -e /pre-pivot/31crypt-cleanup.sh ]

dracut: + . /pre-pivot/31crypt-cleanup.sh

dracut: + cryptsetup luksClose /dev/mapper/luks-*

dracut: + [ -e /pre-pivot/50selinux-loadpolicy.sh ]

dracut: + . /pre-pivot/50selinux-loadpolicy.sh

dracut: + rd_load_policydracut: + SELINUX=enforcing

dracut: + [ -e /sysroot/etc/selinux/config ]

dracut: + . /sysroot/etc/selinux/config

dracut: + SELINUX=enforcing

dracut: + SELINUXTYPE=targeted

dracut: + getarg selinux=0

dracut: + set +x

dracut: + return 1

dracut: + [ 1 -eq 0 -o enforcing = disabled ]

dracut: + permissive=0

dracut: + getarg enforcing=0

dracut: + set +x

dracut: + return 1

dracut: + [ 1 -eq 0 -o enforcing = permissive ]dracut: + [ -x /sysroot/usr/sbin/load_policy -o -x /sysroot/sbin/load_policy ]

dracut: + ret=0

dracut: + info Loading SELinux policy


dracut: + echo dracut: Loading SELinux policy


dracut: + vinfo

dracut: + read line

dracut: + info + [ -x /sysroot/sbin/load_policy ]


dracut: + echo dracut: + [ -x /sysroot/sbin/load_policy ]


dracut: + read line

dracut: + info + chroot /sysroot /sbin/load_policy -idracut: + [ -z yes ]

dracut: + echo dracut: + chroot /sysroot /sbin/load_policy -i


dracut: + read line

dracut: + info + ret=0


dracut: + echo dracut: + ret=0


dracut: + read line

dracut: + [ 0 -eq 0 -o 0 -eq 2 ]

dracut: + return 0

dracut: + [ -e /pre-pivot/90plymouth-newroot.sh ]

dracut: + . /pre-pivot/90plymouth-newroot.sh

dracut: + [ -x /bin/plymouth ]dracut: + /bin/plymouth --newroot=/sysroot

dracut: + getarg init=

dracut: + set +x

dracut: + return 1

dracut: + [ -f /sysroot -a -x /sysroot ]

dracut: + [ -f /sysroot/sbin/init -a -x /sysroot/sbin/init ]

dracut: + INIT=/sbin/init

dracut: + break

dracut: + [ /sbin/init ]

dracut: + getarg rdbreak

dracut: + set +x

dracut: + return 1

dracut: + udevadm control --stop-exec-queue

dracut: + HARD=dracut: + pidof udevd

dracut: + pidof udevd

dracut: + kill 187



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Fedora 12 Dracut

dracut: + kill 186

dracut: + kill 185

dracut: + kill 184

dracut: + kill 183

dracut: + kill 182

dracut: + kill 180

dracut: + kill 179

dracut: + kill 177

dracut: + kill 175dracut: + kill 169

dracut: + kill 166

dracut: + kill 136

dracut: + kill 134

dracut: + kill 133

dracut: + kill 132

dracut: + kill 131

dracut: + kill 130

dracut: + kill 129

dracut: + kill 126

dracut: + kill 124

dracut: + HARD=-9


dracut: + pidof udevddracut: + kill -9 124

dracut: + HARD=-9



dracut: + kill -9 124

dracut: + HARD=-9


dracut: + export -p

dracut: + i=export

dracut: + i=

dracut: + i=

dracut: + [ = root -o = PATH -o = HOME -o = TERM ]

dracut: + unset

dracut: + i=HOME='/'dracut: + i=HOME='/'

dracut: + i=HOME

dracut: + [ HOME = root -o HOME = PATH -o HOME = HOME -o HOME = TERM ]

dracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=KEYBOARDTYPE='pc'

dracut: + i=KEYBOARDTYPE='pc'

dracut: + i=KEYBOARDTYPE

dracut: + [ KEYBOARDTYPE = root -o KEYBOARDTYPE = PATH -o KEYBOARDTYPE = HOME -o KEYBOARDT

YPE = TERM ]

dracut: + unset KEYBOARDTYPEdracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=KEYTABLE='us'

dracut: + i=KEYTABLE='us'

dracut: + i=KEYTABLE

dracut: + [ KEYTABLE = root -o KEYTABLE = PATH -o KEYTABLE = HOME -o KEYTABLE = TERM ]

dracut: + unset KEYTABLE

dracut: + i=export

dracut: + i=

dracut: + i=

dracut: + [ = root -o = PATH -o = HOME -o = TERM ]dracut: + unset

dracut: + i=LANG='en_US.UTF-8'

dracut: + i=LANG='en_US.UTF-8'



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Fedora 12 Dracut

dracut: + i=LANG

dracut: + [ LANG = root -o LANG = PATH -o LANG = HOME -o LANG = TERM ]

dracut: + unset LANG

dracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=PATH='/sbin:/bin:/usr/sbin:/usr/bin'dracut: + i=PATH='/sbin:/bin:/usr/sbin:/usr/bin'

dracut: + i=PATH

dracut: + [ PATH = root -o PATH = PATH -o PATH = HOME -o PATH = TERM ]

dracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=PWD='/'

dracut: + i=PWD='/'

dracut: + i=PWD

dracut: + [ PWD = root -o PWD = PATH -o PWD = HOME -o PWD = TERM ]

dracut: + unset PWD

dracut: + i=exportdracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=SYSFONT='latarcyrheb-sun16'

dracut: + i=SYSFONT='latarcyrheb-sun16'

dracut: + i=SYSFONT

dracut: + [ SYSFONT = root -o SYSFONT = PATH -o SYSFONT = HOME -o SYSFONT = TERM ]

dracut: + unset SYSFONT

dracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unsetdracut: + i=TERM='linux'

dracut: + i=TERM='linux'

dracut: + i=TERM

dracut: + [ TERM = root -o TERM = PATH -o TERM = HOME -o TERM = TERM ]

dracut: + i=export

dracut: + i=

dracut: + i=


dracut: + unset

dracut: + i=ip='eth0:dhcp'

dracut: + i=ip='eth0:dhcp'

dracut: + i=ip

dracut: + [ ip = root -o ip = PATH -o ip = HOME -o ip = TERM ]

dracut: + unset ipdracut: + initargs=

dracut: + getarg init=

dracut: + set +x

dracut: + return 1

dracut: + [ -e /tmp/net.ifaces ]

dracut: + getarg rdcopystate

dracut: + set +x

dracut: + return 1

dracut: + info Switching root


dracut: + echo dracut: Switching root


dracut: + wait_for_loginit

dracut: + getarg rdinitdebugdracut: + set +x

+ exec switch_root /sysroot /sbin/init



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Fedora 12 Dracut

The first thing you will notice is that the init script immediately invokes Plymouth (which I

discussed recently in another post. If you do not want Plymouth to be started by Dracut, add

rd_NO_PLYMOUTH(can anybody explain why part of this option in uppercase?) to the kernel

command line. Note that, according to the man page, this will not work with encrypted partitions.

Turning now to the question of how to build a new initramfs file using Dracut. If you want to build

a generic initramfs file using Dracut, which should be able to boot any bootable configuration

given the appropriate boot flags (root device, network configuration information, etc.) the

following packages must be installed on your system:

cryptsetup-luksq

device-mapperq

iscsi-initiator-utilsq

lvm2q

mdadmq

nbdq

net-tools iprouteq

rpcbind nfs-utilsq

Note that a generic initramfs file is huge. The following three files show the difference in size

between a 2.6.30.96 initrd made using /sbin/mkinitrd , the same one made using Dracut and a

generic one made using Dracut:

-rw-------. 1 root root 3774369 2009-11-11 13:18 /boot/initrd-2.6.30.9-96.fc11.x86_64.img

-rw-r--r--. 1 root root 4163575 2009-11-13 17:19 /boot/initrd-dracut-2.6.30.9-96.fc11.x86

_64.img

-rw-r--r--. 1 root root 14971825 2009-11-13 16:09 /boot/initrd-dracut-generic-2.6.30.9-96.

fc11.x86_64.img

Most of the functionality that Dracut implements is actually implemented by individual Dracut

(generator) modules that are sourced by the main Dracut script to install specific functionality into

the initramfs directory structure using additional functionality provided by

/usr/share/dracut/dracut-functions. Dracut modules live in subdirectories under

/usr/share/dracut/modules.d/. Each module name is prefixed by a two-digit numeric sort code in

the range of 00 to 99, e.g. 50plymouth. Modules with lower numbers are installed first in the

initramfs directory structure. Each module takes 2 standard arguments install and check. Install

is used to install the module functionality onto the initramfs directory structure in a controlled

manner. Mainly this consists of copying files into the initramfs directory structure. The check

option is used by Dracut to check that all the files that the modules needs to install into the

initramfs from the host system are present. Check can take a number of options. For example the-h option is used to check if the functionality implemented by the module is actually being used by

the host system. The -d option outputs a list of other dracut modules that a module has

dependencies on.

The following modules are part of the initial release of Dracut: i18n, network, plymouth, crypt,

dmraid, lvm, mdraid, dmsquash-live, fcoe, iscsi, nbd, nfs, resume, rootfs-block and s390. Let us

example one module, i.e. plymouth, in more detail. This module consists of a total of 8 shell scripts.

(Interestingly, the file utility reports a mix of Bourne shell and POSIX shell scripts!)

# pwd

/usr/share/dracut/modules.d/50plymouth

# ls -l

total 32

http://blog.fpmurphy.com/2009/09/project-plymouth.htmlhttp://blog.fpmurphy.com/2009/09/project-plymouth.html


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Fedora 12 Dracut

-rwxr-xr-x. 1 root root 128 2009-09-29 12:29 check

-rwxr-xr-x. 1 root root 815 2009-09-29 12:29 cryptroot-ask.sh

-rwxr-xr-x. 1 root root 641 2009-09-29 12:29 install

-rwxr-xr-x. 1 root root 191 2009-09-29 12:29 installkernel

-rw-r--r--. 1 root root 52 2009-09-29 12:29 plymouth-emergency.sh

-rwxr-xr-x. 1 root root 79 2009-09-29 12:29 plymouth-newroot.sh

-rwxr-xr-x. 1 root root 1633 2009-09-29 12:29 plymouth-populate-initrd

-rwxr-xr-x. 1 root root 756 2009-09-29 12:29 plymouth-pretrigger.sh

# file *check: Bourne-Again shell script text executable

cryptroot-ask.sh: POSIX shell script text executable

install: Bourne-Again shell script text executable

installkernel: Bourne-Again shell script text executable

plymouth-emergency.sh: ASCII text

plymouth-newroot.sh: POSIX shell script text executable

plymouth-populate-initrd: Bourne-Again shell script text executable

plymouth-pretrigger.sh: POSIX shell script text executable

Here is the install script:

#!/bin/bash

if grep -q nash /usr/libexec/plymouth/plymouth-populate-initrd \

|| ! grep -q PLYMOUTH_POPULATE_SOURCE_FUNCTIONS /usr/libexec/plymouth/plymouth-populate

-initrd \

|| [ ! -x /usr/libexec/plymouth/plymouth-populate-initrd ]; then

. "$moddir"/plymouth-populate-initrd

else

PLYMOUTH_POPULATE_SOURCE_FUNCTIONS="$dracutfunctions" \

/usr/libexec/plymouth/plymouth-populate-initrd -t $initdir

fi

inst_hook pre-pivot 90 "$moddir"/plymouth-newroot.sh

inst_hook pre-trigger 10 "$moddir"/plymouth-pretrigger.sh

inst_hook emergency 50 "$moddir"/plymouth-emergency.sh

inst "$moddir"/cryptroot-ask.sh /sbin/cryptroot-ask

and here is what is in the check script

#!/bin/bash

[[ $1 = -d ]] && echo crypt

[[ -x /sbin/plymouthd && -x /bin/plymouth && -x /usr/sbin/plymouth-set-default-theme ]]

Dracut can have a number of configuration files. The main configuration file is /etc/dracut.conf.

Here is what comes out-of-the-box with Fedora 12.

# Sample dracut config file

# Specific list of dracut modules to use

#dracutmodules=""

# Dracut modules to omit

#omit_dracutmodules=""

# additional kernel modules to the default

#add_drivers=""

# build initrd only to boot current hardware

#hostonly="-h"



11/22

Fedora 12 Dracut

# install local /etc/mdadm.conf

mdadmconf="yes"

# install local /etc/lvm/lvm.conf

lvmconf="yes"

Unfortunately no details of what options can be placed in the configuration file are detailed in the

Dracut man page or elsewhere.

Traditionally on Fedora /sbin/mkinitrd was used to build a new initramfs. Here is the contents of

an initramfs file which was build for a Fedora 11 system using mkinitrd:

init

sbin

etc

etc/ld.so.conf.d

etc/ld.so.conf.d/mysql-x86_64.conf

etc/ld.so.conf.d/kernel-2.6.29.6-217.2.16.fc11.x86_64.conf

etc/ld.so.conf.d/kernel-2.6.30.9-96.fc11.x86_64.conf

etc/ld.so.conf.d/nvidia-lib64.confetc/ld.so.conf.d/atlas-x86_64.conf

etc/ld.so.conf.d/kernel-2.6.29.6-217.2.8.fc11.x86_64.conf

etc/ld.so.conf.d/xulrunner-64.conf

etc/ld.so.conf.d/qt-x86_64.conf

etc/ld.so.conf.d/kernel-2.6.30.5-43.fc11.x86_64.conf

etc/ld.so.cache

etc/sysconfig

etc/sysconfig/i18n

etc/sysconfig/keyboard

etc/lvm

etc/lvm/lvm.conf

etc/fedora-release

etc/system-release

etc/ld.so.confusr

usr/lib64

usr/lib64/plymouth

usr/lib64/plymouth/details.so

usr/lib64/plymouth/text.so

usr/lib64/plymouth/space-flares.so

usr/lib64/libpng12.so.0.37.0

usr/lib64/libnl.so.1

usr/lib64/libelf.so.1

usr/lib64/libnl.so.1.1

usr/lib64/libbdevid.so.6.0.87

usr/lib64/libnash.so.6.0.87

usr/lib64/libpng12.so.0

usr/lib64/libplybootsplash.so.2.0.0usr/lib64/libplybootsplash.so.2

usr/lib64/libelf-0.142.so

usr/share

usr/share/plymouth

usr/share/plymouth/bizcom.png

usr/share/plymouth/themes

usr/share/plymouth/themes/details

usr/share/plymouth/themes/details/details.plymouth

usr/share/plymouth/themes/text

usr/share/plymouth/themes/text/text.plymouth

usr/share/plymouth/themes/default.plymouth

usr/share/plymouth/themes/solar

usr/share/plymouth/themes/solar/progress_bar.png

usr/share/plymouth/themes/solar/star.png

usr/share/plymouth/themes/solar/lock.png

usr/share/plymouth/themes/solar/solar.plymouth

usr/share/plymouth/themes/solar/bullet.png



12/22

Fedora 12 Dracut

usr/share/plymouth/themes/solar/box.png

usr/share/plymouth/themes/solar/entry.png

sys

lib64

lib64/libpopt.so.0.0.0

lib64/libparted-1.8.so.8

lib64/libgcc_s.so.1

lib64/libz.so.1

lib64/libpthread.so.0lib64/libc.so.6

lib64/libpthread-2.10.1.so

lib64/libuuid.so.1

lib64/libpopt.so.0

lib64/libz.so.1.2.3

lib64/libtinfo.so.5.7

lib64/libgcc_s-4.4.1-20090729.so.1

lib64/librt.so.1

lib64/libreadline.so.5

lib64/libdl-2.10.1.so

lib64/libparted-1.8.so.8.0.0

lib64/libglib-2.0.so.0

lib64/libreadline.so.5.2

lib64/libm.so.6lib64/librt-2.10.1.so

lib64/libtinfo.so.5

lib64/libuuid.so.1.2

lib64/libglib-2.0.so.0.2000.5

lib64/libply.so.2.0.0

lib64/libselinux.so.1

lib64/libply.so.2

lib64/libblkid.so.1.0

lib64/libresolv.so.2

lib64/libblkid.so.1

lib64/libsepol.so.1

lib64/libc-2.10.1.so

lib64/libm-2.10.1.so

lib64/libdl.so.2lib64/ld-linux-x86-64.so.2

lib64/ld-2.10.1.so

lib64/libdevmapper.so.1.02

lib64/libresolv-2.10.1.so

bin

bin/nash

bin/setfont

bin/loadkeys

bin/plymouth

bin/plymouthd

bin/modprobe

bin/rmmod

bin/lvm

liblib/kbd

lib/kbd/consolefonts

lib/kbd/consolefonts/latarcyrheb-sun16.psfu

lib/kbd/keymaps

lib/kbd/keymaps/i386

lib/kbd/keymaps/i386/include

lib/kbd/keymaps/i386/include/linux-with-alt-and-altgr.inc

lib/kbd/keymaps/i386/include/linux-keys-bare.inc

lib/kbd/keymaps/i386/include/euro1.map

lib/kbd/keymaps/i386/include/compose.inc

lib/kbd/keymaps/i386/include/qwerty-layout.inc

lib/kbd/keymaps/i386/qwerty

lib/kbd/keymaps/i386/qwerty/us.map

lib/kbd/keymaps/includelib/kbd/keymaps/include/compose.latin4

lib/kbd/keymaps/include/compose.8859_8

lib/kbd/keymaps/include/compose.latin1



13/22

Fedora 12 Dracut




lib/kbd/keymaps/include/compose.latin

lib/modules

lib/modules/2.6.30.9-96.fc11.x86_64

lib/modules/2.6.30.9-96.fc11.x86_64/scsi_wait_scan.ko

lib/modules/2.6.30.9-96.fc11.x86_64/modules.symbols

lib/modules/2.6.30.9-96.fc11.x86_64/modules.alias.binlib/modules/2.6.30.9-96.fc11.x86_64/modules.alias

lib/modules/2.6.30.9-96.fc11.x86_64/modules.symbols.bin

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ofmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.pcimap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.dep

lib/modules/2.6.30.9-96.fc11.x86_64/modules.isapnpmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.dep.bin

lib/modules/2.6.30.9-96.fc11.x86_64/modules.usbmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ccwmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.seriomap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.inputmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ieee1394map

lib/firmware

lib/udevlib/udev/console_init

sysroot

dev

dev/ttyS1

dev/tty6

dev/tty12

dev/tty9

dev/ptmx

dev/tty2

dev/tty

dev/ttyS0

dev/mapper

dev/ttyS2

dev/tty1dev/tty3

dev/tty0

dev/console

dev/tty4

dev/ttyS3

dev/ram0

dev/tty5

dev/null

dev/zero

dev/systty

dev/ram1

dev/tty10

dev/tty11

dev/ramdev/tty8

dev/tty7

proc

16476 blocks

As you can see the script interpreter is nash.

Here is the init script which nash uses to start the boot process.

#!/bin/nash

mount -t proc /proc /proc

setquiet

echo Mounting proc filesystem



14/22

Fedora 12 Dracut

echo Mounting sysfs filesystem

mount -t sysfs /sys /sys

echo Creating /dev

mount -o mode=0755 -t tmpfs /dev /dev

mkdir /dev/pts

mount -t devpts -o gid=5,mode=620 /dev/pts /dev/pts

mkdir /dev/shm

mkdir /dev/mapper

echo Creating initial device nodesmknod /dev/null c 1 3

mknod /dev/zero c 1 5

mknod /dev/systty c 4 0

mknod /dev/tty c 5 0

mknod /dev/console c 5 1

mknod /dev/ptmx c 5 2

mknod /dev/fb c 29 0

mknod /dev/hvc0 c 229 0

mknod /dev/tty0 c 4 0





mknod /dev/tty5 c 4 5mknod /dev/tty6 c 4 6







mknod /dev/ttyS0 c 4 64




daemonize --ignore-missing /bin/plymouthd

echo Setting up hotplug.

hotplug/lib/udev/console_init tty0

plymouth --show-splash

echo Creating block device nodes.

mkblkdevs

echo Creating character device nodes.

mkchardevs

echo Making device-mapper control node

mkdmnod

modprobe scsi_wait_scan

rmmod scsi_wait_scan

mkblkdevs

echo Scanning logical volumes

lvm vgscan --ignorelockingfailure

echo Activating logical volumeslvm vgchange -ay --ignorelockingfailure vg_ultra

resume /dev/mapper/vg_ultra-lv_swap

echo Creating root device.

mkrootdev -t ext4 -o defaults,ro /dev/mapper/vg_ultra-lv_root

echo Mounting root filesystem.

mount /sysroot

cond -ne 0 plymouth --hide-splash

echo Setting up other filesystems.

setuproot

loadpolicy

plymouth --newroot=/sysroot

echo Switching to new root and running init.

switchroot

echo Booting has failed.sleep -1



15/22

Fedora 12 Dracut

In Fedora 12, /sbin/mkinitrd is not available and the shell script /sbin/dracut must be used to build

an initramfs file. Like mkinitrd, this script has numerous options but you will probably never need

to use most of them. Like mkinitrd, the script creates a series of subdirectories and populates

them with assorted files using various Dracut modules from the /usr/share/dracut/modules.d

subdirectories. Finally, it uses the following command line to create the image file:

( cd "$initdir"; find . |cpio -R 0:0 -H newc -o --quiet |gzip -9 > "$outfile"; )

Here is the contents of a functionally equivalent initramfs built on Fedora 11 using /sbin/dracut

instead of/sbin/mkinitrd:

init

initqueue-settled

pre-udev

pre-udev/30block-genrules.sh

pre-udev/30resume-genrules.sh

pre-pivot

pre-pivot/31crypt-cleanup.sh

pre-pivot/50selinux-loadpolicy.sh

pre-pivot/30crypt-cleanup.sh

pre-pivot/90plymouth-newroot.sh

tmp

dracut-002-9.git99fd62e3.fc11

var

var/run

sbin

sbin/initqueue

sbin/cryptsetup

sbin/switch_root

sbin/pidof

sbin/modprobe

sbin/lvm_scan

sbin/udevd

sbin/lvm-cleanup

sbin/rmmod

sbin/lvm

sbin/udevadm

sbin/cryptroot-ask

initqueue

etc

etc/sysconfig

etc/sysconfig/i18n

etc/sysconfig/keyboard

etc/udev

etc/udev/rules.d

etc/udev/rules.d/64-lvm.rules

etc/udev/rules.d/59-persistent-storage-volid.rules

etc/udev/rules.d/61-persistent-storage.rules

etc/udev/rules.d/95-udev-late.rules

etc/udev/rules.d/80-drivers.rules

etc/udev/rules.d/01-ignore.rules

etc/udev/rules.d/60-pcmcia.rules

etc/udev/rules.d/61-persistent-storage-edd.rules

etc/udev/rules.d/50-firmware.rules

etc/udev/rules.d/60-persistent-storage.rules

etc/udev/rules.d/70-luks.rules

etc/udev/rules.d/10-console.rules

etc/udev/rules.d/50-udev-default.rules

etc/udev/udev.conf

etc/lvm

etc/lvm/lvm.conf

etc/modprobe.d



16/22

Fedora 12 Dracut

etc/modprobe.d/dist-oss.conf

etc/modprobe.d/blacklist-visor.conf

etc/modprobe.d/ipv6.conf

etc/modprobe.d/blacklist.conf

etc/modprobe.d/blacklist-nouveau.conf

etc/modprobe.d/floppy-pnp.conf

etc/modprobe.d/dist.conf

etc/modprobe.d/anaconda.conf

etc/fedora-releaseetc/system-release

etc/group

initqueue-finished

usr

usr/sbin

usr/sbin/chroot

usr/lib64

usr/lib64/libusb-0.1.so.4

usr/lib64/plymouth

usr/lib64/plymouth/details.so

usr/lib64/plymouth/text.so

usr/lib64/libpng12.so.0.37.0

usr/lib64/libpng12.so.0

usr/lib64/libplybootsplash.so.2.0.0usr/lib64/libplybootsplash.so.2

usr/lib64/libusb-0.1.so.4.4.4

usr/bin

usr/bin/flock

usr/lib

usr/share

usr/share/plymouth

usr/share/plymouth/bizcom.png

usr/share/plymouth/themes

usr/share/plymouth/themes/details

usr/share/plymouth/themes/details/details.plymouth

usr/share/plymouth/themes/text

usr/share/plymouth/themes/text/text.plymouth

usr/share/plymouth/themes/default.plymouthsys

emergency

emergency/50plymouth-emergency.sh

lib64

lib64/libgpg-error.so.0.4.0

lib64/libpopt.so.0.0.0

lib64/libnss_files-2.10.1.so

lib64/libz.so.1

lib64/libpthread.so.0

lib64/libattr.so.1.1.0

lib64/libc.so.6

lib64/libpthread-2.10.1.so

lib64/libuuid.so.1

lib64/libvolume_id.so.1lib64/libpopt.so.0

lib64/libz.so.1.2.3

lib64/libtinfo.so.5.7

lib64/libudev.so.0

lib64/librt.so.1

lib64/libreadline.so.5

lib64/libcryptsetup.so.0.0.0

lib64/libdl-2.10.1.so

lib64/libglib-2.0.so.0

lib64/libreadline.so.5.2

lib64/libm.so.6

lib64/libvolume_id.so.1.1.0

lib64/libacl.so.1

lib64/librt-2.10.1.solib64/libtinfo.so.5

lib64/libuuid.so.1.2

lib64/libcap.so.2



17/22

Fedora 12 Dracut

lib64/libgcrypt.so.11

lib64/libglib-2.0.so.0.2000.5

lib64/libudev.so.0.2.0

lib64/libply.so.2.0.0

lib64/libacl.so.1.1.0

lib64/libselinux.so.1

lib64/libply.so.2

lib64/libcryptsetup.so.0

lib64/libblkid.so.1.0lib64/libgcrypt.so.11.5.2

lib64/libblkid.so.1

lib64/libsepol.so.1

lib64/libc-2.10.1.so

lib64/libcap.so.2.16

lib64/libm-2.10.1.so

lib64/libdl.so.2

lib64/ld-linux-x86-64.so.2

lib64/libattr.so.1

lib64/ld-2.10.1.so

lib64/libdevmapper.so.1.02

lib64/libgpg-error.so.0

lib64/libnss_files.so.2

binbin/setfont

bin/cp

bin/loadkeys

bin/plymouth

bin/uname

bin/ln

bin/mkdir

bin/cat

bin/rm

bin/plymouthd

bin/sleep

bin/basename

bin/sh

bin/mknodbin/ls

bin/mount

bin/mv

bin/sed

bin/dmesg

bin/dash

mount

mount/99mount-root.sh

mount/10resume.sh

lib

lib/dracut-lib.sh

lib/kbd

lib/kbd/consolefonts

lib/kbd/consolefonts/latarcyrheb-sun16.psfulib/kbd/keymaps

lib/kbd/keymaps/i386

lib/kbd/keymaps/i386/include

lib/kbd/keymaps/i386/include/linux-with-alt-and-altgr.inc

lib/kbd/keymaps/i386/include/linux-keys-bare.inc

lib/kbd/keymaps/i386/include/euro1.map

lib/kbd/keymaps/i386/include/compose.inc

lib/kbd/keymaps/i386/include/qwerty-layout.inc

lib/kbd/keymaps/i386/qwerty

lib/kbd/keymaps/i386/qwerty/us.map

lib/kbd/keymaps/include



lib/kbd/keymaps/include/compose.latin1lib/kbd/keymaps/include/compose.latin3





18/22

Fedora 12 Dracut

lib/kbd/keymaps/include/compose.latin

lib/modules

lib/modules/2.6.30.9-96.fc11.x86_64

lib/modules/2.6.30.9-96.fc11.x86_64/modules.symbols

lib/modules/2.6.30.9-96.fc11.x86_64/modules.alias.bin

lib/modules/2.6.30.9-96.fc11.x86_64/modules.alias

lib/modules/2.6.30.9-96.fc11.x86_64/modules.symbols.bin

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ofmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.pcimaplib/modules/2.6.30.9-96.fc11.x86_64/modules.dep

lib/modules/2.6.30.9-96.fc11.x86_64/modules.isapnpmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.dep.bin

lib/modules/2.6.30.9-96.fc11.x86_64/modules.usbmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ccwmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.seriomap

lib/modules/2.6.30.9-96.fc11.x86_64/kernel

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/i2c

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/i2c/algos

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/i2c/algos/i2c-algo-bit.ko

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/i2c/i2c-core.ko

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/scsi

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/scsi/scsi_wait_scan.kolib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/gpu

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/gpu/drm

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/gpu/drm/drm.ko

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/gpu/drm/nouveau

lib/modules/2.6.30.9-96.fc11.x86_64/kernel/drivers/gpu/drm/nouveau/nouveau.ko

lib/modules/2.6.30.9-96.fc11.x86_64/modules.inputmap

lib/modules/2.6.30.9-96.fc11.x86_64/modules.ieee1394map

lib/udev

lib/udev/edd_id

lib/udev/hid2hci

lib/udev/vol_id

lib/udev/firmware.sh

lib/udev/usb_id

lib/udev/ata_idlib/udev/pcmcia-socket-startup

lib/udev/rules.d

lib/udev/fw_unit_symlinks.sh

lib/udev/pcmcia-check-broken-cis

lib/udev/scsi_id

lib/udev/console_init

lib/udev/path_id

lib/udev/create_floppy_devices

lib/udev/cdrom_id

lib/terminfo

lib/terminfo/d

lib/terminfo/d/dumb

lib/terminfo/a

lib/terminfo/a/ansilib/terminfo/l

lib/terminfo/l/linux

lib/terminfo/v

lib/terminfo/v/vt100-nav

lib/terminfo/v/vt100



lib/terminfo/v/vt100-am

lib/terminfo/v/vt52


cmdline

cmdline/30parse-lvm.sh

cmdline/01version.sh

cmdline/10parse-root-opts.shcmdline/30parse-crypt.sh

cmdline/20parse-blacklist.sh

cmdline/95parse-block.sh



19/22

Fedora 12 Dracut

cmdline/20parse-i18n.sh

cmdline/10parse-resume.sh

pre-trigger

pre-trigger/10plymouth-pretrigger.sh

sysroot

dev

dev/pts

proc

Note that the nash script interpreter is not part of the initramfs image. Instead /bin/dash is

included. The following is the contents of the init script from this initramfs. As you can see it is

significantly different from the init script included in the initramfs built using /sbin/mkinitrd.

#!/bin/sh

#

# Licensed under the GPLv2

#

# Copyright 2008, Red Hat, Inc.

# Jeremy Katz

emergency_shell()

{

exec >/dev/console 2>&1 /dev/null 2>&1

mount -t sysfs /sys /sys >/dev/null 2>&1

if [ ! -c /dev/ptmx ]; then

# try to mount devtmpfs

if ! mount -t devtmpfs -omode=0755 udev /dev >/dev/null 2>&1; then

# if it failed fall back to normal tmpfs

mount -t tmpfs -omode=0755 udev /dev >/dev/null 2>&1

# Make some basic devices first, let udev handle the rest

mknod /dev/null c 1 3

mknod /dev/ptmx c 5 2

mknod /dev/console c 5 1

mknod /dev/kmsg c 1 11fi

fi

if getarg rdinitdebug; then

set -x

fi

mkdir /dev/shm

mkdir /dev/pts

mount -t devpts -o gid=5,mode=620 /dev/pts /dev/pts >/dev/null 2>&1

UDEVVERSION=$(udevadm --version)

source_conf /etc/conf.d# run scriptlets to parse the command line

getarg 'rdbreak=cmdline' && emergency_shell "Break before cmdline"

source_all cmdline

[ -z "$root" ] && die "No or empty root= argument"

[ -z "$rootok" ] && die "Don't know how to handle 'root=$root'"

# Network root scripts may need updated root= options,

# so deposit them where they can see them (udev purges the env)

{

echo "root='$root'"

echo "rflags='$rflags'"

echo "fstype='$fstype'"

echo "netroot='$netroot'"echo "NEWROOT='$NEWROOT'"

} > /tmp/root.info



20/22

Fedora 12 Dracut

# pre-udev scripts run before udev starts, and are run only once.

getarg 'rdbreak=pre-udev' && emergency_shell "Break before pre-udev"

source_all pre-udev

# start up udev and trigger cold plugs

udevd --daemon

UDEV_LOG_PRIO_ARG=--log-priority

UDEV_QUEUE_EMPTY="udevadm settle --timeout=0"

if [ $UDEVVERSION -lt 140 ]; then

UDEV_LOG_PRIO_ARG=--log_priority

UDEV_QUEUE_EMPTY="udevadm settle --timeout=1"

fi

getarg rdudevinfo && udevadm control $UDEV_LOG_PRIO_ARG=info

getarg rdudevdebug && udevadm control $UDEV_LOG_PRIO_ARG=debug

getarg 'rdbreak=pre-trigger' && emergency_shell "Break before pre-trigger"

source_all pre-trigger

# then the rest

udevadm trigger $udevtriggeropts >/dev/null 2>&1

getarg 'rdbreak=initqueue' && emergency_shell "Break before initqueue"

i=0

while :; do

check_finished && break

udevsettle

check_finished && break

if [ -f /initqueue/work ]; then

rm /initqueue/work

fi

for job in /initqueue/*.sh; do

[ -e "$job" ] || break

job=$job . $job

check_finished && break 2

done

$UDEV_QUEUE_EMPTY >/dev/null 2>&1 || continue

modprobe scsi_wait_scan && rmmod scsi_wait_scan


for job in /initqueue-settled/*.sh; do[ -e "$job" ] || break

job=$job . $job

check_finished && break 2

done


# no more udev jobs and queues empty.

sleep 0.5

i=$(($i+1))

[ $i -gt 20 ] \

&& { flock -s 9 ; emergency_shell "No root device found"; } 9>/.console_lock

done

unset jobunset queuetriggered

# pre-mount happens before we try to mount the root filesystem,



21/22

Fedora 12 Dracut

# and happens once.

getarg 'rdbreak=pre-mount' && emergency_shell "Break pre-mount"

source_all pre-mount

getarg 'rdbreak=mount' && emergency_shell "Break mount"

# mount scripts actually try to mount the root filesystem, and may

# be sourced any number of times. As soon as one suceeds, no more are sourced.

i=0

while :; do[ -d "$NEWROOT/proc" ] && break;

for f in /mount/*.sh; do

[ -f "$f" ] && . "$f"

[ -d "$NEWROOT/proc" ] && break;

done

i=$(($i+1))

[ $i -gt 20 ] \

&& { flock -s 9 ; emergency_shell "Can't mount root filesystem"; } 9>/.console_loc

k

done

{

echo -n "Mounted root filesystem "while read dev mp rest; do [ "$mp" = "$NEWROOT" ] && echo $dev; done /dev/null 2>&1; d

o

for pid in $(pidof udevd); do

kill $HARD $pid >/dev/null 2>&1

done

HARD="-9"

done

# Clean up the environment

for i in $(export -p); do

i=${i#declare -x}

i=${i#export}

i=${i%%=*}

[ "$i" = "root" -o "$i" = "PATH" -o "$i" = "HOME" -o "$i" = "TERM" ] || unset $idone

initargs=""

if getarg init= >/dev/null ; then

ignoreargs="console BOOT_IMAGE"

# only pass arguments after init= to the init

read CLINE /dev/null 2>&1

mkdir -p /dev/.initramfs/state/etc/sysconfig/network-scripts/

cp /tmp/resolv.conf /dev/.initramfs/state/etc/ >/dev/null 2>&1

echo "files /etc/sysconfig/network-scripts" > /dev/.initramfs/rwtab

cp -a /tmp/ifcfg/* /dev/.initramfs/state/etc/sysconfig/network-scripts/ >/dev/null 2>&

1

fi

# Debug: Copy state

if getarg rdcopystate; then

cp /tmp/* /dev/.initramfs/ >/dev/null 2>&1

fi

info "Switching root"

exec switch_root "$NEWROOT" "$INIT" $initargs || {

echo "Something went very badly wrong in the initramfs. Please "

echo "file a bug against dracut."

emergency_shell

}

Note the use ofudev to discover devices, the use of/sysroot for mounting filesystems, and how

breakpoints are handled. The purpose of the /sbin/switch_root executable is similar to the



22/22

Fedora 12 Dracut

switchroot command in nash. Basically it changes the current directory to /, removes a lot of

temporary subdirectories, chroots . and execs the init process.

Well, hopefully I have covered Dracut in sufficient detail to enable you to understand what has

changed in Fedora 12 with respect to the boot process and building an initramfs file. The changes

are significant and I expect that it will be a while before all the corner cases are found and fixed. If

I have missed anything important regarding Dracut in this post, please add the information via a

comment so that others can share in the knowledge.

fedora 12 dracut

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