DESCRIPTION¶
dracut.conf is loaded during the initialisation phase of
dracut. Command line parameter will override any values set here.
*.conf files are read from /usr/lib/dracut/dracut.conf.d
and /etc/dracut.conf.d. Files with the same name in /etc/dracut.conf.d will
replace files in /usr/lib/dracut/dracut.conf.d. The files are then read in
alphanumerical order and will override parameters set in
/etc/dracut.conf. Each line specifies an attribute and a value. A
# indicates the beginning of a comment; following characters, up to
the end of the line are not interpreted.
dracut command line options will override any values set here.
Configuration files must have the extension .conf; other
extensions are ignored.
add_dracutmodules+=" <dracut
modules> "
Add a space-separated list of dracut modules to call when
building the initramfs. Modules are located in
/usr/lib/dracut/modules.d.
force_add_dracutmodules+=" <dracut
modules> "
Force to add a space-separated list of dracut modules to
the default set of modules, when host-only mode is specified. This parameter
can be specified multiple times.
omit_dracutmodules+=" <dracut
modules> "
Omit a space-separated list of dracut modules to call
when building the initramfs. Modules are located in
/usr/lib/dracut/modules.d.
dracutmodules+=" <dracut
modules> "
Specify a space-separated list of dracut modules to call
when building the initramfs. Modules are located in
/usr/lib/dracut/modules.d. This option forces dracut to only include
the specified dracut modules. In most cases the "add_dracutmodules"
option is what you want to use.
add_drivers+=" <kernel
modules> "
Specify a space-separated list of kernel modules to add
to the initramfs. The kernel modules have to be specified without the
".ko" suffix.
force_drivers+=" <list of kernel
modules> "
See add_drivers above. But in this case it is ensured
that the drivers are tried to be loaded early via modprobe.
omit_drivers+=" <kernel
modules> "
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.
drivers+=" <kernel
modules> "
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.
filesystems+=" <filesystem
names> "
Specify a space-separated list of kernel filesystem
modules to exclusively include in the generic initramfs.
drivers_dir="<kernel modules
directory>"
Specify the directory where to look for kernel
modules.
fw_dir+=" :<dir>[:<dir> ...] "
Specify additional colon-separated list of directories
where to look for firmware files.
libdirs+=" <dir>[
<dir> ...] "
Specify a space-separated list of directories where to
look for libraries.
install_items+=" <file>[
<file> ...] "
Specify additional files to include in the initramfs,
separated by spaces.
install_optional_items+=" <file>[
<file> ...] "
Specify additional files to include in the initramfs,
separated by spaces, if they exist.
compress="{cat|bzip2|lzma|xz|gzip|lzop|lz4|zstd|<compressor
[args ...]>}"
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 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. To disable
compression, use "cat".
squash_compress="{<compressor [args
...]>}"
Compress the squashfs image using the passed compressor
and compressor specific options for mksquashfs. You can refer to mksquashfs
manual for supported compressors and compressor specific options. If squash
module is not called when building the initramfs, this option will not take
effect.
do_strip="{yes|no}"
Strip binaries in the initramfs (default=yes).
aggressive_strip="{yes|no}"
Strip more than just debug symbol and sections, for a
smaller initramfs build. The "do_strip=yes" option must also be
specified (default=no).
do_hardlink="{yes|no}"
Hardlink files in the initramfs (default=yes).
prefix=" <directory> "
Prefix initramfs files with
<directory>.
hostonly="{yes|no}"
Host-only mode: Install only what is needed for booting
the local host instead of a generic host and generate host-specific
configuration (default=no).
hostonly_mode="{sloppy|strict}"
Specify the host-only mode to use (default=sloppy). In
"sloppy" host-only mode, extra drivers and modules will be
installed, so minor hardware change won’t make the image unbootable
(e.g. changed keyboard), and the image is still portable among similar hosts.
With "strict" mode enabled, anything not necessary for booting the
local host in its current state will not be included, and modules may do some
extra job to save more space. Minor change of hardware or environment could
make the image unbootable.
hostonly_cmdline="{yes|no}"
If set to "yes", store the kernel command line
arguments needed in the initramfs. If hostonly="yes" and this
option is not configured, it’s automatically set to
"yes".
hostonly_nics+=" [<nic>[
<nic> ...]] "
Only enable listed NICs in the initramfs. The list can be
empty, so other modules can install only the necessary network drivers.
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"), or "mapper" to use
/dev/mapper device names (default=mapper).
tmpdir="<temporary directory>"
Specify temporary directory to use.
Warning
If chrooted to another root other than the real root device, use
--fstab and provide a valid /etc/fstab.
use_fstab="{yes|no}"
Use /etc/fstab instead of
/proc/self/mountinfo (default=no).
add_fstab+=" <filename> "
Add entries of <filename> to the initramfs
/etc/fstab.
add_device+=" <device> "
Bring up <device> in initramfs,
<device> should be the device name. This can be useful in
host-only mode for resume support when your swap is on LVM an encrypted
partition.
mdadmconf="{yes|no}"
Include local /etc/mdadm.conf (default=no).
lvmconf="{yes|no}"
Include local /etc/lvm/lvm.conf
(default=no).
fscks=" <fsck
tools> "
Add a space-separated list of fsck tools. If nothing is
specified, the default is: "umount mount /sbin/fsck* xfs_db xfs_check
xfs_repair e2fsck jfs_fsck reiserfsck btrfsck". The installation is
opportunistic (non-existing tools are ignored).
nofscks="{yes|no}"
If specified, inhibit installation of any fsck tools
(default=no).
ro_mnt="{yes|no}"
Mount / and /usr read-only by default
(default=no).
kernel_cmdline="parameters"
Specify default kernel command line parameters.
kernel_only="{yes|no}"
Only install kernel drivers and firmware files
(default=no).
no_kernel="{yes|no}"
Do not install kernel drivers and firmware files
(default=no).
acpi_override="{yes|no}"
[WARNING] ONLY USE THIS IF YOU KNOW WHAT YOU ARE DOING!
Override BIOS provided ACPI tables. For further documentation read
Documentation/acpi/initrd_table_override.txt in the kernel sources. Search
for ACPI table files (must have .aml suffix) in acpi_table_dir= directory
(see below) and add them to a separate uncompressed cpio archive. This cpio
archive gets glued (concatenated, uncompressed one must be the first one) to
the compressed cpio archive. The first, uncompressed cpio archive is for
data which the kernel must be able to access very early (and cannot make use
of uncompress algorithms yet) like microcode or ACPI tables
(default=no).
acpi_table_dir="<dir>"
Directory to search for ACPI tables if acpi_override= is
set to yes.
early_microcode="{yes|no}"
Combine early microcode with ramdisk (default=yes).
stdloglvl="{0-6}"
Specify logging level for standard error
(default=4).
Note
Logging levels:
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)
sysloglvl="{0-6}"
Specify logging level for syslog (default=0).
fileloglvl="{0-6}"
Specify logging level for logfile (default=4).
logfile="<file>"
Path to logfile.
sshkey="<file>"
SSH key file used with ssh-client module.
show_modules="{yes|no}"
Print the name of the included modules to standard output
during build (default=no).
i18n_vars="<variable mapping>"
Distribution specific variable mapping. See
dracut/modules.d/10i18n/README for a detailed description.
i18n_default_font="<fontname>"
The font <fontname> to install, if not specified
otherwise. Default is "eurlatgr".
i18n_install_all="{yes|no}"
Install everything regardless of generic or host-only
mode (default=no).
reproducible="{yes|no}"
Create reproducible images (default=no).
noimageifnotneeded="{yes|no}"
Do not create an image in host-only mode, if no kernel
driver is needed and no /etc/cmdline/*.conf will be generated into the
initramfs (default=no).
loginstall="<directory>"
Log all files installed from the host to
<directory>.
uefi="{yes|no}"
Instead of creating an initramfs image, dracut will
create an UEFI executable, which can be executed by an UEFI BIOS (default=no).
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.
machine_id="{yes|no}"
Affects the default output filename of the UEFI
executable, including the <MACHINE_ID> part (default=yes).
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.
uefi_splash_image="<file>"
Specifies the UEFI stub loader’s splash image.
Requires bitmap (.bmp) image format.
uefi_secureboot_cert="<file>",
uefi_secureboot_key="<file>"
Specifies a certificate and corresponding key, which are
used to sign the created UEFI executable. Requires both certificate and key
need to be specified and sbsign to be installed.
uefi_secureboot_engine="parameter"
Specifies an engine to use when signing the created UEFI
executable. E.g. "pkcs11"
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>.
enhanced_cpio="{yes|no}"
Attempt to use the dracut-cpio binary, which optimizes
archive creation for copy-on-write filesystems (default=no). When specified,
initramfs archives are also padded to ensure optimal data alignment for extent
sharing. To retain reflink data deduplication benefits, this should be used
alongside the compress="cat" and
do_strip="no" parameters, with initramfs source files,
tmpdir staging area and destination all on the same copy-on-write
capable filesystem.
parallel="{yes|no}"
If set to yes, try to execute tasks in parallel
(currently only supported for --regenerate-all).
