NAME
----
-dracut - low-level tool for generating an initramfs image
+dracut - low-level tool for generating an initramfs/initrd image
SYNOPSIS
--------
-*dracut* ['OPTION...'] [<image> [_<kernel version>_]]
+*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.
as initial root file system. All finding of the root device happens in this
early userspace.
-For a complete list of kernel command line options see *dracut.cmdline*(7)
+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
+-----
+
+include::dracut.usage.asc[]
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
+----
+
**-f, --force**::
overwrite existing initramfs file.
-**-m, --modules** _<list of 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
- parameter can be specified multiple times.
+**-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:
----
-# dracut --modules "module1 module2" ...
+# dracut --add "module1 module2" ...
----
===============================
-**-o, --omit** _<list of dracut modules>_::
- omit a space-separated list of dracut modules. This parameter can be
- specified multiple times.
-
+**--force-add** _<list of dracut modules>_::
+ 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:
----
-# dracut --omit "module1 module2" ...
+# dracut --force-add "module1 module2" ...
----
===============================
-**-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.
+**-o, --omit** _<list of dracut modules>_::
+ 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:
----
-# dracut --add "module1 module2" ...
+# dracut --omit "module1 module2" ...
----
===============================
-**--force-add** _<list of dracut modules>_::
- 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.
+**-m, --modules** _<list of 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
+ 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:
----
-# dracut --force-add "module1 module2" ...
+# dracut --modules "module1 module2" ...
----
===============================
----
===============================
+**--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.
++
+[NOTE]
+===============================
+If [LIST] has multiple arguments, then you have to put these in quotes. For
+example:
+----
+# dracut --force-drivers "kmodule1 kmodule2" ...
+----
+===============================
+
**--omit-drivers** _<list of kernel modules>_::
specify a space-separated list of kernel modules not to add to the
initramfs.
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
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_
**--nostrip**::
do not strip 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
**--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
provide a valid _/etc/fstab_.
====
-**--no-hostonly**::
+**-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
+
+**--no-hostonly-default-device**:
+ Do not generate implicit host devices like root, swap, fstab, etc.
+ Use "--mount" or "--add-device" to explicitly add devices as needed.
+
+**--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-fstab** _<filename>_::
Add entries of _<filename>_ to the initramfs /etc/fstab.
-**--mount** "_<device>_ _<mountpoint>_ _<filesystem type>_ _<filesystem options>_"::
- Mount _<device>_ on _<mountpoint>_ with _<filesystem type>_ and _<filesystem
- options>_ in the initramfs
-
-**-i, --include** _<SOURCE>_ _<TARGET>_::
+**--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>_::
+**-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:
-+
----
# dracut --install "/bin/foo /sbin/bar" ...
----
===============================
+**--install-optional** _<file list>_::
+ 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
[WARNING]
====
Make sure your kernel has lzma decompression support compiled in, otherwise you
-will not be able to boot. Equivalent to "--compress=lzma -9"
+will not be able to boot. Equivalent to "lzma --compress=lzma -9"
====
**--xz**::
[WARNING]
====
Make sure your kernel has xz decompression support compiled in, otherwise you
-will not be able to boot. Equivalent to "--compress=xz --check=crc32
---lzma2=dict=1MiB"
+will not be able to boot. Equivalent to
+"lzma --compress=xz --check=crc32 --lzma2=dict=1MiB"
+====
+
+**--lzo**::
+ Compress the generated initramfs using lzop.
+[WARNING]
+====
+Make sure your kernel has lzo decompression support compiled in, otherwise you
+will not be able to boot.
+====
+
+**--lz4**::
+ Compress the generated initramfs using lz4.
+[WARNING]
+====
+Make sure your kernel has lz4 decompression support compiled in, otherwise you
+will not be able to boot.
+====
+
+**--zstd**::
+ Compress the generated initramfs using Zstandard.
+[WARNING]
+====
+Make sure your kernel has zstd decompression support compiled in, otherwise you
+will not be able to boot.
====
**--compress** _<compressor>_::
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.
**--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**::
+ 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
+ _$prefix/lib/systemd/boot/efi/linux<EFI-MACHINE-TYPE-NAME>.efi.stub_
+ or _$prefix/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_COMPRESS_::
+ sets the default compression program. See **--compress**.
+
FILES
-----
_/var/log/dracut.log_::
_/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/_::
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
AUTHORS
-------
-*Harald Hoyer*::
- Project Leader and Developer
+Harald Hoyer
-*Victor Lowther*::
- Developer
+Victor Lowther
-*Philippe Seewer*::
- Developer
+Philippe Seewer
-*Warren Togami*::
- Developer
+Warren Togami
-*Amadeusz Żołnowski*::
- Developer
+Amadeusz Żołnowski
-*Jeremy Katz*::
- Developer
+Jeremy Katz
-*David Dillow*::
- Developer
+David Dillow
-*Will Woods*::
- Developer
+Will Woods
SEE ALSO
--------
-*dracut.cmdline*(7) *dracut.conf*(5)
+*dracut.cmdline*(7) *dracut.conf*(5) *lsinitrd*(1)
projects / thirdparty / dracut.git / blobdiff