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DRACUT(8) | dracut | DRACUT(8) |
NAME¶
dracut - low-level tool for generating an initramfs/initrd imageSYNOPSIS¶
dracut [OPTION...] [<image> [<kernel version>]]DESCRIPTION¶
Create an initramfs <image> for the kernel with the version <kernel version>. If <kernel version> is omitted, then the version of the actual running kernel is used. If <image> is omitted or empty, then the default location /boot/initramfs-<kernel version>.img is used. dracut creates an initial image used by the kernel for preloading the block device modules (such as IDE, SCSI or RAID) which are needed to access the root filesystem, mounting the root filesystem and booting into the real system. At boot time, the kernel unpacks that archive into RAM disk, mounts and uses it as initial root file system. All finding of the root device happens in this early userspace. Initramfs images are also called "initrd". For a complete list of kernel command line options see dracut.cmdline(7). If you are dropped to an emergency shell, while booting your initramfs, the file /run/initramfs/rdsosreport.txt is created, which can be saved to a (to be mounted by hand) partition (usually /boot) or a USB stick. Additional debugging info can be produced by adding rd.debug to the kernel command line. /run/initramfs/rdsosreport.txt contains all logs and the output of some tools. It should be attached to any report about dracut problems.USAGE¶
To create a initramfs image, the most simple command is:# dracut
# dracut --force
# dracut foobar.img
# dracut foobar.img 2.6.40-1.rc5.f20
# dracut --kver 2.6.40-1.rc5.f20
Inspecting the Contents¶
To see the contents of the image created by dracut, you can use the lsinitrd tool.# lsinitrd | less
# lsinitrd -f /etc/ld.so.conf include ld.so.conf.d/*.conf
Adding dracut Modules¶
Some dracut modules are turned off by default and have to be activated manually. You can do this by adding the dracut modules to the configuration file /etc/dracut.conf or /etc/dracut.conf.d/myconf.conf. See dracut.conf(5). You can also add dracut modules on the command line by using the -a or --add option:# dracut --add bootchart initramfs-bootchart.img
# dracut --list-modules
Omitting dracut Modules¶
Sometimes you don’t want a dracut module to be included for reasons of speed, size or functionality. To do this, either specify the omit_dracutmodules variable in the dracut.conf or /etc/dracut.conf.d/myconf.conf configuration file (see dracut.conf(5)), or use the -o or --omit option on the command line:# dracut -o "multipath lvm" no-multipath-lvm.img
Adding Kernel Modules¶
If you need a special kernel module in the initramfs, which is not automatically picked up by dracut, you have the use the --add-drivers option on the command line or the drivers vaiable in the /etc/dracut.conf or /etc/dracut.conf.d/myconf.conf configuration file (see dracut.conf(5)):# dracut --add-drivers mymod initramfs-with-mymod.img
Boot parameters¶
An initramfs generated without the "hostonly" mode, does not contain any system configuration files (except for some special exceptions), so the configuration has to be done on the kernel command line. With this flexibility, you can easily boot from a changed root partition, without the need to recompile the initramfs image. So, you could completly change your root partition (move it inside a md raid with encryption and LVM on top), as long as you specify the correct filesystem LABEL or UUID on the kernel command line for your root device, dracut will find it and boot from it. The kernel command line can also be provided by the dhcp server with the root-path option. See the section called “Network Boot”. For a full reference of all kernel command line parameters, see dracut.cmdline(5). To get a quick start for the suitable kernel command line on your system, use the --print-cmdline option:# dracut --print-cmdline root=UUID=8b8b6f91-95c7-4da2-831b-171e12179081 rootflags=rw,relatime,discard,data=ordered rootfstype=ext4
This is the only option dracut really needs to boot from your root partition.
Because your root partition can live in various environments, there are a lot
of formats for the root= option. The most basic one is root= <path to
device node>:
Because device node names can change, dependent on the drive ordering, you are
encouraged to use the filesystem identifier (UUID) or filesystem label (LABEL)
to specify your root partition:
or
To see all UUIDs or LABELs on your system, do:
or
If your root partition is on the network see the section called “Network
Boot”.
root=/dev/sda2
root=UUID=19e9dda3-5a38-484d-a9b0-fa6b067d0331
root=LABEL=myrootpartitionlabel
# ls -l /dev/disk/by-uuid
# ls -l /dev/disk/by-label
If you have to input passwords for encrypted disk volumes, you might want to set
the keyboard layout and specify a display font.
A typical german kernel command would contain:
Setting these options can override the setting stored on your system, if you use
a modern init system, like systemd.
rd.vconsole.font=latarcyrheb-sun16 rd.vconsole.keymap=de-latin1-nodeadkeys rd.locale.LANG=de_DE.UTF-8
Sometimes it is required to prevent the automatic kernel module loading of a
specific kernel module. To do this, just add rd.blacklist= <kernel
module name>, with <kernel module name> not containing the
.ko suffix, to the kernel command line. For example:
The option can be specified multiple times on the kernel command line.
rd.driver.blacklist=mptsas rd.driver.blacklist=nouveau
If you want to speed up the boot process, you can specify as much information
for dracut on the kernel command as possible. For example, you can tell
dracut, that you root partition is not on a LVM volume or not on a raid
partition, or that it lives inside a specific crypto LUKS encrypted volume. By
default, dracut searches everywhere. A typical dracut kernel command line for
a plain primary or logical partition would contain:
This turns off every automatic assembly of LVM, MD raids, DM raids and crypto
LUKS.
Of course, you could also omit the dracut modules in the initramfs creation
process, but then you would lose the posibility to turn it on on demand.
rd.luks=0 rd.lvm=0 rd.md=0 rd.dm=0
Injecting custom Files¶
To add your own files to the initramfs image, you have several possibilities. The --include option let you specify a source path and a target path. For example# dracut --include cmdline-preset /etc/cmdline.d/mycmdline.conf initramfs-cmdline-pre.img
# mkdir -p rd.live.overlay/etc/cmdline.d # mkdir -p rd.live.overlay/etc/conf.d # echo "ip=dhcp" >> rd.live.overlay/etc/cmdline.d/mycmdline.conf # echo export FOO=testtest >> rd.live.overlay/etc/conf.d/testvar.conf # echo export BAR=testtest >> rd.live.overlay/etc/conf.d/testvar.conf # tree rd.live.overlay/ rd.live.overlay/ `-- etc |-- cmdline.d | `-- mycmdline.conf `-- conf.d `-- testvar.conf # dracut --include rd.live.overlay / initramfs-rd.live.overlay.img
# dracut --install 'strace fsck.ext3 ssh' initramfs-dbg.img
Network Boot¶
If your root partition is on a network drive, you have to have the network dracut modules installed to create a network aware initramfs image. If you specify ip=dhcp on the kernel command line, then dracut asks a dhcp server about the ip adress for the machine. The dhcp server can also serve an additional root-path, which will set the root device for dracut. With this mechanism, you have static configuration on your client machine and a centralized boot configuration on your TFTP/DHCP server. If you can’t pass a kernel command line, then you can inject /etc/cmdline.d/mycmdline.conf, with a method described in the section called “Injecting custom Files”.
To reduce the size of the initramfs, you should create it with by ommitting all
dracut modules, which you know, you don’t need to boot the machine.
You can also specify the exact dracut and kernel modules to produce a very tiny
initramfs image.
For example for a NFS image, you would do:
Then you would boot from this image with your target machine and reduce the size
once more by creating it on the target machine with the --host-only option:
This will reduce the size of the initramfs image significantly.
# dracut -m "nfs network base" initramfs-nfs-only.img
# dracut -m "nfs network base" --host-only initramfs-nfs-host-only.img
TROUBLESHOOTING¶
If the boot process does not succeed, you have several options to debug the situation. Some of the basic operations are covered here. For more information you should also visit: https://www.kernel.org/pub/linux/utils/boot/dracut/dracut.htmlIdentifying your problem area¶
1.Remove 'rhgb' and 'quiet' from the
kernel command line
2.Add 'rd.shell' to the kernel command line. This
will present a shell should dracut be unable to locate your root device
3.Add 'rd.shell rd.debug log_buf_len=1M' to the
kernel command line so that dracut shell commands are printed as they are
executed
4.The file /run/initramfs/rdsosreport.txt is generated,
which contains all the logs and the output of all significant tools, which are
mentioned later.
If you want to save that output, simply mount /boot by hand or insert an USB
stick and mount that. Then you can store the output for later inspection.
Information to include in your report¶
All bug reports
In all cases, the following should be mentioned and attached to your bug report:
•The exact kernel command-line used. Typically
from the bootloader configuration file (e.g. /boot/grub2/grub.cfg) or
from /proc/cmdline.
•A copy of your disk partition information from
/etc/fstab, which might be obtained booting an old working initramfs or
a rescue medium.
•Turn on dracut debugging (see the
debugging dracut section), and attach the file
/run/initramfs/rdsosreport.txt.
•If you use a dracut configuration file, please
include /etc/dracut.conf and all files in
/etc/dracut.conf.d/*.conf
This section details information to include when experiencing problems on a
system whose root device is located on a network attached volume (e.g. iSCSI,
NFS or NBD). As well as the information from the section called “All
bug reports”, include the following information:
•Please include the output of
# /sbin/ifup <interfacename> # ip addr show
Debugging dracut¶
Configure a serial console
Successfully debugging dracut will require some form of console logging during
the system boot. This section documents configuring a serial console
connection to record boot messages.
1.First, enable serial console output for both the
kernel and the bootloader.
2.Open the file /boot/grub2/grub.cfg for editing.
Below the line 'timeout=5', add the following:
serial --unit=0 --speed=9600 terminal --timeout=5 serial console
3.Also in /boot/grub2/grub.cfg, add the following
boot arguemnts to the 'kernel' line:
console=tty0 console=ttyS0,9600
4.When finished, the /boot/grub2/grub.cfg file
should look similar to the example below.
default=0 timeout=5 serial --unit=0 --speed=9600 terminal --timeout=5 serial console title Fedora (2.6.29.5-191.fc11.x86_64) root (hd0,0) kernel /vmlinuz-2.6.29.5-191.fc11.x86_64 ro root=/dev/mapper/vg_uc1-lv_root console=tty0 console=ttyS0,9600 initrd /dracut-2.6.29.5-191.fc11.x86_64.img
5.More detailed information on how to configure the
kernel for console output can be found at
http://www.faqs.org/docs/Linux-HOWTO/Remote-Serial-Console-HOWTO.html#CONFIGURE-KERNEL.
6.Redirecting non-interactive output
Note
You can redirect all non-interactive output to /dev/kmsg and the kernel
will put it out on the console when it reaches the kernel buffer by doing
# exec >/dev/kmsg 2>&1 </dev/console
dracut offers a shell for interactive debugging in the event dracut fails to
locate your root filesystem. To enable the shell:
1.Add the boot parameter 'rd.shell' to your
bootloader configuration file (e.g. /boot/grub2/grub.cfg)
2.Remove the boot arguments 'rhgb' and
'quiet'
A sample /boot/grub2/grub.cfg bootloader configuration file is listed
below.
default=0 timeout=5 serial --unit=0 --speed=9600 terminal --timeout=5 serial console title Fedora (2.6.29.5-191.fc11.x86_64) root (hd0,0) kernel /vmlinuz-2.6.29.5-191.fc11.x86_64 ro root=/dev/mapper/vg_uc1-lv_root console=tty0 rd.shell initrd /dracut-2.6.29.5-191.fc11.x86_64.img
3.If system boot fails, you will be dropped into a shell
as seen in the example below.
No root device found Dropping to debug shell. #
4.Use this shell prompt to gather the information
requested above (see the section called “All bug
reports”).
From the dracut debug shell, you can manually perform the task of locating and
preparing your root volume for boot. The required steps will depend on how
your root volume is configured. Common scenarios include:
•A block device (e.g. /dev/sda7)
•A LVM logical volume (e.g.
/dev/VolGroup00/LogVol00)
•An encrypted device (e.g.
/dev/mapper/luks-4d5972ea-901c-4584-bd75-1da802417d83)
•A network attached device (e.g.
netroot=iscsi:@192.168.0.4::3260::iqn.2009-02.org.example:for.all)
The exact method for locating and preparing will vary. However, to continue with
a successful boot, the objective is to locate your root volume and create a
symlink /dev/root which points to the file system. For example, the
following example demonstrates accessing and booting a root volume that is an
encrypted LVM Logical volume.
1.Inspect your partitions using parted
# parted /dev/sda -s p Model: ATA HTS541060G9AT00 (scsi) Disk /dev/sda: 60.0GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 32.3kB 10.8GB 107MB primary ext4 boot 2 10.8GB 55.6GB 44.7GB logical lvm
2.You recall that your root volume was a LVM logical
volume. Scan and activate any logical volumes.
# lvm vgscan # lvm vgchange -ay
3.You should see any logical volumes now using the
command blkid:
# blkid /dev/sda1: UUID="3de247f3-5de4-4a44-afc5-1fe179750cf7" TYPE="ext4" /dev/sda2: UUID="Ek4dQw-cOtq-5MJu-OGRF-xz5k-O2l8-wdDj0I" TYPE="LVM2_member" /dev/mapper/linux-root: UUID="def0269e-424b-4752-acf3-1077bf96ad2c" TYPE="crypto_LUKS" /dev/mapper/linux-home: UUID="c69127c1-f153-4ea2-b58e-4cbfa9257c5e" TYPE="ext3" /dev/mapper/linux-swap: UUID="47b4d329-975c-4c08-b218-f9c9bf3635f1" TYPE="swap"
4.From the output above, you recall that your root
volume exists on an encrypted block device. Following the guidance disk
encryption guidance from the Installation Guide, you unlock your encrypted
root volume.
# UUID=$(cryptsetup luksUUID /dev/mapper/linux-root) # cryptsetup luksOpen /dev/mapper/linux-root luks-$UUID Enter passphrase for /dev/mapper/linux-root: Key slot 0 unlocked.
5.Next, make a symbolic link to the unlocked root volume
# ln -s /dev/mapper/luks-$UUID /dev/root
6.With the root volume available, you may continue
booting the system by exiting the dracut shell
# exit
For more debugging options, see dracut.cmdline(7).
To debug the shutdown sequence on systemd systems, you can rd.break on
pre-shutdown or shutdown.
To do this from an already booted system:
This will give you a dracut shell after the system pivot’ed back in the
initramfs.
# mkdir -p /run/initramfs/etc/cmdline.d # echo "rd.debug rd.break=pre-shutdown rd.break=shutdown" > /run/initramfs/etc/cmdline.d/debug.conf # touch /run/initramfs/.need_shutdown
OPTIONS¶
--kver <kernel version>set the kernel version. This enables to specify the
kernel version, without specifying the location of the initramfs image. For
example:
# dracut --kver 3.5.0-0.rc7.git1.2.fc18.x86_64
overwrite existing initramfs file.
-a, --add <list of dracut modules>
add a space-separated list of dracut modules to the
default set of modules. This parameter can be specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--force-add <list of dracut modules>
# dracut --add "module1 module2" ...
force to add a space-separated list of dracut modules to
the default set of modules, when -H is specified. This parameter can be
specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
-o, --omit <list of dracut modules>
# dracut --force-add "module1 module2" ...
omit a space-separated list of dracut modules. This
parameter can be specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
-m, --modules <list of dracut modules>
# dracut --omit "module1 module2" ...
specify a space-separated list of dracut modules to call
when building the initramfs. Modules are located in
/usr/lib/dracut/modules.d. This parameter can be specified multiple
times. This option forces dracut to only include the specified dracut modules.
In most cases the "--add" option is what you want to use.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
-d, --drivers <list of kernel modules>
# dracut --modules "module1 module2" ...
specify a space-separated list of kernel modules to
exclusively include in the initramfs. The kernel modules have to be specified
without the ".ko" suffix. This parameter can be specified multiple
times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--add-drivers <list of kernel modules>
# dracut --drivers "kmodule1 kmodule2" ...
specify a space-separated list of kernel modules to add
to the initramfs. The kernel modules have to be specified without the
".ko" suffix. This parameter can be specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--force-drivers <list of kernel modules>
# dracut --add-drivers "kmodule1 kmodule2" ...
See add-drivers above. But in this case it is ensured
that the drivers are tried to be loaded early via modprobe.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--omit-drivers <list of kernel modules>
# dracut --force-drivers "kmodule1 kmodule2" ...
specify a space-separated list of kernel modules not to
add to the initramfs. The kernel modules have to be specified without the
".ko" suffix. This parameter can be specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--filesystems <list of filesystems>
# dracut --omit-drivers "kmodule1 kmodule2" ...
specify a space-separated list of kernel filesystem
modules to exclusively include in the generic initramfs. This parameter can be
specified multiple times.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
-k, --kmoddir <kernel directory>
# dracut --filesystems "filesystem1 filesystem2" ...
specify the directory, where to look for kernel
modules
--fwdir <dir>[:<dir>...]++
specify additional directories, where to look for
firmwares. This parameter can be specified multiple times.
--kernel-cmdline <parameters>
specify default kernel command line parameters
--kernel-only
only install kernel drivers and firmware files
--no-kernel
do not install kernel drivers and firmware files
--early-microcode
Combine early microcode with ramdisk
--no-early-microcode
Do not combine early microcode with ramdisk
--print-cmdline
print the kernel command line for the current disk
layout
--mdadmconf
include local /etc/mdadm.conf
--nomdadmconf
do not include local /etc/mdadm.conf
--lvmconf
include local /etc/lvm/lvm.conf
--nolvmconf
do not include local /etc/lvm/lvm.conf
--fscks [LIST]
add a space-separated list of fsck tools, in addition to
dracut.conf's specification; the installation is opportunistic
(non-existing tools are ignored)
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--nofscks
# dracut --fscks "fsck.foo barfsck" ...
inhibit installation of any fsck tools
--strip
strip binaries in the initramfs (default)
--nostrip
do not strip binaries in the initramfs
--prelink
prelink binaries in the initramfs (default)
--noprelink
do not prelink binaries in the initramfs
--hardlink
hardlink files in the initramfs (default)
--nohardlink
do not hardlink files in the initramfs
--prefix <dir>
prefix initramfs files with the specified directory
--noprefix
do not prefix initramfs files (default)
-h, --help
display help text and exit.
--debug
output debug information of the build process
-v, --verbose
increase verbosity level (default is info(4))
-q, --quiet
decrease verbosity level (default is info(4))
-c, --conf <dracut configuration file>
specify configuration file to use.
Default: /etc/dracut.conf
--confdir <configuration directory>
specify configuration directory to use.
Default: /etc/dracut.conf.d
--tmpdir <temporary directory>
specify temporary directory to use.
Default: /var/tmp
--sshkey <sshkey file>
ssh key file used with ssh-client module.
--logfile <logfile>
logfile to use; overrides any setting from the
configuration files.
Default: /var/log/dracut.log
-l, --local
activates the local mode. dracut will use modules from
the current working directory instead of the system-wide installed modules in
/usr/lib/dracut/modules.d. This is useful when running dracut from a
git checkout.
-H, --hostonly
Host-Only mode: Install only what is needed for booting
the local host instead of a generic host and generate host-specific
configuration.
Warning
If chrooted to another root other than the real root device, use
"--fstab" and provide a valid /etc/fstab.
-N, --no-hostonly
Disable Host-Only mode
--hostonly-cmdline: Store kernel command line arguments needed in the
initramfs
--no-hostonly-cmdline: Do not store kernel command line arguments needed
in the initramfs
--hostonly-i18n: Install only needed keyboard and font files according to
the host configuration (default).
--no-hostonly-i18n: Install all keyboard and font files available.
--persistent-policy <policy>
Use <policy> to address disks and
partitions. <policy> can be any directory name found in
/dev/disk. E.g. "by-uuid", "by-label"
--fstab
Use /etc/fstab instead of
/proc/self/mountinfo.
--add-fstab <filename>
Add entries of <filename> to the initramfs
/etc/fstab.
--mount "<device> <mountpoint>
<filesystem type> [ <filesystem options>
[<dump frequency> [ <fsck order>]]]"
Mount <device> on <mountpoint>
with <filesystem type> in the initramfs. <filesystem
options>, <dump options> and <fsck order> can
be specified, see fstab manpage for the details. The default <filesystem
options> is "defaults". The default <dump
frequency> is "0". the default <fsck order> is
"2".
--mount "<mountpoint>"
Like above, but <device>, <filesystem
type> and <filesystem options> are determined by looking
at the current mounts.
--add-device <device>
Bring up <device> in initramfs,
<device> should be the device name. This can be useful in
hostonly mode for resume support when your swap is on LVM or an encrypted
partition. [NB --device can be used for compatibility with earlier
releases]
-i, --include <SOURCE> <TARGET>
include the files in the SOURCE directory into the TARGET
directory in the final initramfs. If SOURCE is a file, it will be installed to
TARGET in the final initramfs. This parameter can be specified multiple
times.
-I, --install <file list>
install the space separated list of files into the
initramfs.
Note
If [LIST] has multiple arguments, then you have to put these in quotes. For
example:
--install-optional <file list>
# dracut --install "/bin/foo /sbin/bar" ...
install the space separated list of files into the
initramfs, if they exist.
--gzip
Compress the generated initramfs using gzip. This will be
done by default, unless another compression option or --no-compress is passed.
Equivalent to "--compress=gzip -9"
--bzip2
Compress the generated initramfs using bzip2.
Warning
Make sure your kernel has bzip2 decompression support compiled in, otherwise you
will not be able to boot. Equivalent to "--compress=bzip2"
--lzma
Compress the generated initramfs using lzma.
Warning
Make sure your kernel has lzma decompression support compiled in, otherwise you
will not be able to boot. Equivalent to "lzma --compress=lzma -9"
--xz
Compress the generated initramfs using xz.
Warning
Make sure your kernel has xz decompression support compiled in, otherwise you
will not be able to boot. Equivalent to "lzma --compress=xz --check=crc32
--lzma2=dict=1MiB"
--lzo
Compress the generated initramfs using lzop.
Compress the generated initramfs using lz4.
Compress the generated initramfs using the passed
compression program. If you pass it just the name of a compression program, it
will call that program with known-working arguments. If you pass a quoted
string with arguments, it will be called with exactly those arguments.
Depending on what you pass, this may result in an initramfs that the kernel
cannot decompress. The default value can also be set via the
INITRD_COMPRESS environment variable.
--no-compress
Do not compress the generated initramfs. This will
override any other compression options.
--reproducible
Create reproducible images.
--no-reproducible
Do not create reproducible images.
--list-modules
List all available dracut modules.
-M, --show-modules
Print included module’s name to standard output
during build.
--keep
Keep the initramfs temporary directory for debugging
purposes.
--printsize
Print out the module install size
--profile: Output profile information of the build process
--ro-mnt: Mount / and /usr read-only by default.
-L, --stdlog <level>
[0-6] Specify logging level (to standard error)
0 - suppress any messages 1 - only fatal errors 2 - all errors 3 - warnings 4 - info 5 - debug info (here starts lots of output) 6 - trace info (and even more)
Regenerate all initramfs images at the default location
with the kernel versions found on the system. Additional parameters are passed
through.
--loginstall <DIR>
Log all files installed from the host to
<DIR>.
--uefi
Instead of creating an initramfs image, dracut will
create an UEFI executable, which can be executed by an UEFI BIOS. The default
output filename is
<EFI>/EFI/Linux/linux-$kernel$-<MACHINE_ID>-<BUILD_ID>.efi.
<EFI> might be /efi, /boot or /boot/efi depending
on where the ESP partition is mounted. The <BUILD_ID> is taken from
BUILD_ID in /usr/lib/os-release or if it exists /etc/os-release
and is left out, if BUILD_ID is non-existant or empty.
--no-machineid
affects the default output filename of --uefi and
will discard the <MACHINE_ID> part.
--uefi-stub <FILE>
Specifies the UEFI stub loader, which will load the
attached kernel, initramfs and kernel command line and boots the kernel. The
default is
/lib/systemd/boot/efi/linux<EFI-MACHINE-TYPE-NAME>.efi.stub or
/usr/lib/gummiboot/linux<EFI-MACHINE-TYPE-NAME>.efi.stub
--kernel-image <FILE>
Specifies the kernel image, which to include in the UEFI
executable. The default is /lib/modules/<KERNEL-VERSION>/vmlinuz
or /boot/vmlinuz-<KERNEL-VERSION>
ENVIRONMENT¶
INITRD_COMPRESSsets the default compression program. See
--compress.
FILES¶
/var/log/dracut.loglogfile of initramfs image creation
/tmp/dracut.log
logfile of initramfs image creation, if
/var/log/dracut.log is not writable
/etc/dracut.conf
see dracut.conf5
/etc/dracut.conf.d/*.conf
see dracut.conf5
/usr/lib/dracut/dracut.conf.d/*.conf
see dracut.conf5
Configuration in the initramfs¶
/etc/conf.d/Any files found in /etc/conf.d/ will be sourced in
the initramfs to set initial values. Command line options will override these
values set in the configuration files.
/etc/cmdline
Can contain additional command line options. Deprecated,
better use /etc/cmdline.d/*.conf.
/etc/cmdline.d/*.conf
Can contain additional command line options.
AVAILABILITY¶
The dracut command is part of the dracut package and is available from https://dracut.wiki.kernel.orgAUTHORS¶
Harald Hoyer Victor Lowther Philippe Seewer Warren Togami Amadeusz Żołnowski Jeremy Katz David Dillow Will WoodsSEE ALSO¶
dracut.cmdline(7) dracut.conf(5) lsinitrd(1)01/24/2017 | dracut |