1DRACUT.CONF(5) dracut DRACUT.CONF(5)
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6 dracut.conf - configuration file(s) for dracut
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9 /etc/dracut.conf /etc/dracut.conf.d/*.conf
10 /usr/lib/dracut/dracut.conf.d/*.conf
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13 dracut.conf is loaded during the initialisation phase of dracut.
14 Command line parameter will override any values set here.
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16 *.conf files are read from /usr/lib/dracut/dracut.conf.d and
17 /etc/dracut.conf.d. Files with the same name in /etc/dracut.conf.d will
18 replace files in /usr/lib/dracut/dracut.conf.d. The files are then read
19 in alphanumerical order and will override parameters set in
20 /etc/dracut.conf. Each line specifies an attribute and a value. A #
21 indicates the beginning of a comment; following characters, up to the
22 end of the line are not interpreted.
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24 dracut command line options will override any values set here.
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26 Configuration files must have the extension .conf; other extensions are
27 ignored.
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29 add_dracutmodules+=" <dracut modules> "
30 Add a space-separated list of dracut modules to call when building
31 the initramfs. Modules are located in /usr/lib/dracut/modules.d.
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33 force_add_dracutmodules+=" <dracut modules> "
34 Force to add a space-separated list of dracut modules to the
35 default set of modules, when host-only mode is specified. This
36 parameter can be specified multiple times.
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38 omit_dracutmodules+=" <dracut modules> "
39 Omit a space-separated list of dracut modules to call when building
40 the initramfs. Modules are located in /usr/lib/dracut/modules.d.
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42 dracutmodules+=" <dracut modules> "
43 Specify a space-separated list of dracut modules to call when
44 building the initramfs. Modules are located in
45 /usr/lib/dracut/modules.d. This option forces dracut to only
46 include the specified dracut modules. In most cases the
47 "add_dracutmodules" option is what you want to use.
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49 add_drivers+=" <kernel modules> "
50 Specify a space-separated list of kernel modules to add to the
51 initramfs. The kernel modules have to be specified without the
52 ".ko" suffix.
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54 force_drivers+=" <list of kernel modules> "
55 See add_drivers above. But in this case it is ensured that the
56 drivers are tried to be loaded early via modprobe.
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58 omit_drivers+=" <kernel modules> "
59 Specify a space-separated list of kernel modules not to add to the
60 initramfs. The kernel modules have to be specified without the
61 ".ko" suffix.
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63 drivers+=" <kernel modules> "
64 Specify a space-separated list of kernel modules to exclusively
65 include in the initramfs. The kernel modules have to be specified
66 without the ".ko" suffix.
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68 filesystems+=" <filesystem names> "
69 Specify a space-separated list of kernel filesystem modules to
70 exclusively include in the generic initramfs.
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72 drivers_dir="<kernel modules directory>"
73 Specify the directory where to look for kernel modules.
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75 fw_dir+=" :<dir>[:<dir> ...] "
76 Specify additional colon-separated list of directories where to
77 look for firmware files.
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79 libdirs+=" <dir>[ <dir> ...] "
80 Specify a space-separated list of directories where to look for
81 libraries.
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83 install_items+=" <file>[ <file> ...] "
84 Specify additional files to include in the initramfs, separated by
85 spaces.
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87 install_optional_items+=" <file>[ <file> ...] "
88 Specify additional files to include in the initramfs, separated by
89 spaces, if they exist.
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91 compress="{cat|bzip2|lzma|xz|gzip|lzop|lz4|zstd|<compressor [args
92 ...]>}"
93 Compress the generated initramfs using the passed compression
94 program. If you pass it just the name of a compression program, it
95 will call that program with known-working arguments. If you pass
96 arguments, it will be called with exactly those arguments.
97 Depending on what you pass, this may result in an initramfs that
98 the kernel cannot decompress. To disable compression, use "cat".
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100 squash_compress="{<compressor [args ...]>}"
101 Compress the squashfs image using the passed compressor and
102 compressor specific options for mksquashfs. You can refer to
103 mksquashfs manual for supported compressors and compressor specific
104 options. If squash module is not called when building the
105 initramfs, this option will not take effect.
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107 do_strip="{yes|no}"
108 Strip binaries in the initramfs (default=yes).
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110 aggressive_strip="{yes|no}"
111 Strip more than just debug symbol and sections, for a smaller
112 initramfs build. The "do_strip=yes" option must also be specified
113 (default=no).
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115 do_hardlink="{yes|no}"
116 Hardlink files in the initramfs (default=yes).
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118 prefix=" <directory> "
119 Prefix initramfs files with <directory>.
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121 hostonly="{yes|no}"
122 Host-only mode: Install only what is needed for booting the local
123 host instead of a generic host and generate host-specific
124 configuration (default=no).
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126 hostonly_mode="{sloppy|strict}"
127 Specify the host-only mode to use (default=sloppy). In "sloppy"
128 host-only mode, extra drivers and modules will be installed, so
129 minor hardware change won’t make the image unbootable (e.g. changed
130 keyboard), and the image is still portable among similar hosts.
131 With "strict" mode enabled, anything not necessary for booting the
132 local host in its current state will not be included, and modules
133 may do some extra job to save more space. Minor change of hardware
134 or environment could make the image unbootable.
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136 hostonly_cmdline="{yes|no}"
137 If set to "yes", store the kernel command line arguments needed in
138 the initramfs. If hostonly="yes" and this option is not configured,
139 it’s automatically set to "yes".
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141 hostonly_nics+=" [<nic>[ <nic> ...]] "
142 Only enable listed NICs in the initramfs. The list can be empty, so
143 other modules can install only the necessary network drivers.
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145 persistent_policy="<policy>"
146 Use <policy> to address disks and partitions. <policy> can be any
147 directory name found in /dev/disk (e.g. "by-uuid", "by-label"), or
148 "mapper" to use /dev/mapper device names (default=mapper).
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150 tmpdir="<temporary directory>"
151 Specify temporary directory to use.
152
153 Warning
154 If chrooted to another root other than the real root device, use
155 --fstab and provide a valid /etc/fstab.
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157 use_fstab="{yes|no}"
158 Use /etc/fstab instead of /proc/self/mountinfo (default=no).
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160 add_fstab+=" <filename> "
161 Add entries of <filename> to the initramfs /etc/fstab.
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163 add_device+=" <device> "
164 Bring up <device> in initramfs, <device> should be the device name.
165 This can be useful in host-only mode for resume support when your
166 swap is on LVM an encrypted partition.
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168 mdadmconf="{yes|no}"
169 Include local /etc/mdadm.conf (default=no).
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171 lvmconf="{yes|no}"
172 Include local /etc/lvm/lvm.conf (default=no).
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174 fscks=" <fsck tools> "
175 Add a space-separated list of fsck tools. If nothing is specified,
176 the default is: "umount mount /sbin/fsck* xfs_db xfs_check
177 xfs_repair e2fsck jfs_fsck reiserfsck btrfsck". The installation is
178 opportunistic (non-existing tools are ignored).
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180 nofscks="{yes|no}"
181 If specified, inhibit installation of any fsck tools (default=no).
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183 ro_mnt="{yes|no}"
184 Mount / and /usr read-only by default (default=no).
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186 kernel_cmdline="parameters"
187 Specify default kernel command line parameters.
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189 kernel_only="{yes|no}"
190 Only install kernel drivers and firmware files (default=no).
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192 no_kernel="{yes|no}"
193 Do not install kernel drivers and firmware files (default=no).
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195 acpi_override="{yes|no}"
196 [WARNING] ONLY USE THIS IF YOU KNOW WHAT YOU ARE DOING!
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198 Override BIOS provided ACPI tables. For further documentation read
199 Documentation/acpi/initrd_table_override.txt in the kernel sources.
200 Search for ACPI table files (must have .aml suffix) in
201 acpi_table_dir= directory (see below) and add them to a separate
202 uncompressed cpio archive. This cpio archive gets glued
203 (concatenated, uncompressed one must be the first one) to the
204 compressed cpio archive. The first, uncompressed cpio archive is
205 for data which the kernel must be able to access very early (and
206 cannot make use of uncompress algorithms yet) like microcode or
207 ACPI tables (default=no).
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209 acpi_table_dir="<dir>"
210 Directory to search for ACPI tables if acpi_override= is set to
211 yes.
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213 early_microcode="{yes|no}"
214 Combine early microcode with ramdisk (default=yes).
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216 stdloglvl="{0-6}"
217 Specify logging level for standard error (default=4).
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219 Note
220 Logging levels:
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222 0 - suppress any messages
223 1 - only fatal errors
224 2 - all errors
225 3 - warnings
226 4 - info
227 5 - debug info (here starts lots of output)
228 6 - trace info (and even more)
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230 sysloglvl="{0-6}"
231 Specify logging level for syslog (default=0).
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233 fileloglvl="{0-6}"
234 Specify logging level for logfile (default=4).
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236 logfile="<file>"
237 Path to logfile.
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239 sshkey="<file>"
240 SSH key file used with ssh-client module.
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242 show_modules="{yes|no}"
243 Print the name of the included modules to standard output during
244 build (default=no).
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246 i18n_vars="<variable mapping>"
247 Distribution specific variable mapping. See
248 dracut/modules.d/10i18n/README for a detailed description.
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250 i18n_default_font="<fontname>"
251 The font <fontname> to install, if not specified otherwise. Default
252 is "eurlatgr".
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254 i18n_install_all="{yes|no}"
255 Install everything regardless of generic or host-only mode
256 (default=no).
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258 reproducible="{yes|no}"
259 Create reproducible images (default=no).
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261 noimageifnotneeded="{yes|no}"
262 Do not create an image in host-only mode, if no kernel driver is
263 needed and no /etc/cmdline/*.conf will be generated into the
264 initramfs (default=no).
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266 loginstall="<directory>"
267 Log all files installed from the host to <directory>.
268
269 uefi="{yes|no}"
270 Instead of creating an initramfs image, dracut will create an UEFI
271 executable, which can be executed by an UEFI BIOS (default=no). The
272 default output filename is
273 <EFI>/EFI/Linux/linux-$kernel$-<MACHINE_ID>-<BUILD_ID>.efi. <EFI>
274 might be /efi, /boot or /boot/efi depending on where the ESP
275 partition is mounted. The <BUILD_ID> is taken from BUILD_ID in
276 /usr/lib/os-release or if it exists /etc/os-release and is left
277 out, if BUILD_ID is non-existant or empty.
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279 machine_id="{yes|no}"
280 Affects the default output filename of the UEFI executable,
281 including the <MACHINE_ID> part (default=yes).
282
283 uefi_stub="<file>"
284 Specifies the UEFI stub loader, which will load the attached
285 kernel, initramfs and kernel command line and boots the kernel. The
286 default is
287 /lib/systemd/boot/efi/linux<EFI-MACHINE-TYPE-NAME>.efi.stub.
288
289 uefi_splash_image="<file>"
290 Specifies the UEFI stub loader’s splash image. Requires bitmap
291 (.bmp) image format.
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293 uefi_secureboot_cert="<file>", uefi_secureboot_key="<file>"
294 Specifies a certificate and corresponding key, which are used to
295 sign the created UEFI executable. Requires both certificate and key
296 need to be specified and sbsign to be installed.
297
298 uefi_secureboot_engine="parameter"
299 Specifies an engine to use when signing the created UEFI
300 executable. E.g. "pkcs11"
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302 kernel_image="<file>"
303 Specifies the kernel image, which to include in the UEFI
304 executable. The default is /lib/modules/<KERNEL-VERSION>/vmlinuz or
305 /boot/vmlinuz-<KERNEL-VERSION>.
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307 enhanced_cpio="{yes|no}"
308 Attempt to use the dracut-cpio binary, which optimizes archive
309 creation for copy-on-write filesystems (default=no). When
310 specified, initramfs archives are also padded to ensure optimal
311 data alignment for extent sharing. To retain reflink data
312 deduplication benefits, this should be used alongside the
313 compress="cat" and do_strip="no" parameters, with initramfs source
314 files, tmpdir staging area and destination all on the same
315 copy-on-write capable filesystem.
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317 parallel="{yes|no}"
318 If set to yes, try to execute tasks in parallel (currently only
319 supported for --regenerate-all).
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322 /etc/dracut.conf
323 Old configuration file. You better use your own file in
324 /etc/dracut.conf.d/.
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326 /etc/dracut.conf.d/
327 Any /etc/dracut.conf.d/*.conf file can override the values in
328 /etc/dracut.conf. The configuration files are read in
329 alphanumerical order.
330
332 Harald Hoyer
333
335 dracut(8) dracut.cmdline(7)
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339dracut b15d29d 11/16/2023 DRACUT.CONF(5)