dracut.8.asc

   1 DRACUT(8)
   2 =========
   3 :doctype: manpage
   4 :man source:   dracut
   5 :man manual:   dracut
   6
   7 NAME
   8 ----
   9 dracut - low-level tool for generating an initramfs image
  10
  11 SYNOPSIS
  12 --------
  13 *dracut* [__OPTION...__] [__<image>__ [__<kernel version>__]]
  14
  15 DESCRIPTION
  16 -----------
  17
  18 Create an initramfs <image> for the kernel with the version <kernel version>.
  19 If <kernel version> is omitted, then the version of the actual running
  20 kernel is used. If <image> is omitted or empty, then the default location
  21 /boot/initramfs-<kernel version>.img is used.
  22
  23 dracut creates an initial image used by the kernel for preloading the block
  24 device modules (such as IDE, SCSI or RAID) which are needed to access the root
  25 filesystem, mounting the root filesystem and booting into the real system.
  26
  27 At boot time, the kernel unpacks that archive into RAM disk, mounts and uses it
  28 as initial root file system. All finding of the root device happens in this
  29 early userspace.
  30
  31 For a complete list of kernel command line options see *dracut.cmdline*(7).
  32
  33 If you are dropped to an emergency shell, while booting your initramfs,
  34 the file _/run/initramfs/rdsosreport.txt_ is created, which can be saved to a
  35 (to be mounted by hand) partition (usually /boot) or a USB stick.
  36 Additional debugging info can be produced by adding **rd.debug** to the kernel
  37 command line. _/run/initramfs/rdsosreport.txt_ contains all logs and the output
  38 of some tools. It should be attached to any report about dracut problems.
  39
  40 USAGE
  41 -----
  42
  43 include::dracut.usage.asc[]
  44
  45 OPTIONS
  46 -------
  47 **--kver** _<kernel version>_::
  48     set the kernel version. This enables to specify the kernel version, without
  49     specifying the location of the initramfs image. For example:
  50 ----
  51 # dracut --kver 3.5.0-0.rc7.git1.2.fc18.x86_64
  52 ----
  53
  54 **-f, --force**::
  55     overwrite existing initramfs file.
  56
  57 **-m, --modules** _<list of dracut modules>_::
  58     specify a space-separated list of dracut modules to call when building the
  59     initramfs. Modules are located in _/usr/lib/dracut/modules.d_. This
  60     parameter can be specified multiple times.
  61 +
  62 [NOTE]
  63 ===============================
  64 If [LIST] has multiple arguments, then you have to put these in quotes. For
  65 example:
  66 ----
  67 # dracut --modules "module1 module2"  ...
  68 ----
  69 ===============================
  70
  71 **-o, --omit** _<list of dracut modules>_::
  72     omit a space-separated list of dracut modules. This parameter can be
  73     specified multiple times.
  74 +
  75 [NOTE]
  76 ===============================
  77 If [LIST] has multiple arguments, then you have to put these in quotes. For
  78 example:
  79 ----
  80 # dracut --omit "module1 module2"  ...
  81 ----
  82 ===============================
  83
  84 **-a, --add** _<list of dracut modules>_::
  85     add a space-separated list of dracut modules to the default set of modules.
  86     This parameter can be specified multiple times.
  87 +
  88 [NOTE]
  89 ===============================
  90 If [LIST] has multiple arguments, then you have to put these in quotes. For
  91 example:
  92 ----
  93 # dracut --add "module1 module2"  ...
  94 ----
  95 ===============================
  96
  97 **--force-add** _<list of dracut modules>_::
  98     force to add a space-separated list of dracut modules to the default set of
  99     modules, when -H is specified. This parameter can be specified multiple
 100     times.
 101 +
 102 [NOTE]
 103 ===============================
 104 If [LIST] has multiple arguments, then you have to put these in quotes. For
 105 example:
 106 ----
 107 # dracut --force-add "module1 module2"  ...
 108 ----
 109 ===============================
 110
 111 **-d, --drivers** _<list of kernel modules>_::
 112     specify a space-separated list of kernel modules to exclusively include
 113     in the initramfs. The kernel modules have to be specified without the ".ko"
 114     suffix. This parameter can be specified multiple times.
 115 +
 116 [NOTE]
 117 ===============================
 118 If [LIST] has multiple arguments, then you have to put these in quotes. For
 119 example:
 120 ----
 121 # dracut --drivers "kmodule1 kmodule2"  ...
 122 ----
 123 ===============================
 124
 125 **--add-drivers** _<list of kernel modules>_::
 126     specify a space-separated list of kernel modules to add to the initramfs.
 127     The kernel modules have to be specified without the ".ko" suffix. This
 128     parameter can be specified multiple times.
 129 +
 130 [NOTE]
 131 ===============================
 132 If [LIST] has multiple arguments, then you have to put these in quotes. For
 133 example:
 134 ----
 135 # dracut --add-drivers "kmodule1 kmodule2"  ...
 136 ----
 137 ===============================
 138
 139 **--force-drivers** _<list of kernel modules>_::
 140     See add-drivers above. But in this case it is ensured that the drivers
 141     are tried to be loaded early via modprobe.
 142 +
 143 [NOTE]
 144 ===============================
 145 If [LIST] has multiple arguments, then you have to put these in quotes. For
 146 example:
 147 ----
 148 # dracut --force-drivers "kmodule1 kmodule2"  ...
 149 ----
 150 ===============================
 151
 152 **--omit-drivers** _<list of kernel modules>_::
 153     specify a space-separated list of kernel modules not to add to the
 154     initramfs.
 155     The kernel modules have to be specified without the ".ko" suffix. This
 156     parameter can be specified multiple times.
 157 +
 158 [NOTE]
 159 ===============================
 160 If [LIST] has multiple arguments, then you have to put these in quotes. For
 161 example:
 162 ----
 163 # dracut --omit-drivers "kmodule1 kmodule2"  ...
 164 ----
 165 ===============================
 166
 167 **--filesystems** _<list of filesystems>_::
 168     specify a space-separated list of kernel filesystem modules to exclusively
 169     include in the generic initramfs. This parameter can be specified multiple
 170     times.
 171 +
 172 [NOTE]
 173 ===============================
 174 If [LIST] has multiple arguments, then you have to put these in quotes. For
 175 example:
 176 ----
 177 # dracut --filesystems "filesystem1 filesystem2"  ...
 178 ----
 179 ===============================
 180
 181 **-k, --kmoddir** _<kernel directory>_::
 182     specify the directory, where to look for kernel modules
 183
 184 **--fwdir** _<dir>[:<dir>...]++_::
 185     specify additional directories, where to look for firmwares. This parameter
 186     can be specified multiple times.
 187
 188 **--kernel-cmdline <parameters>**::
 189     specify default kernel command line parameters
 190
 191
 192 **--kernel-only**::
 193     only install kernel drivers and firmware files
 194
 195 **--no-kernel**::
 196     do not install kernel drivers and firmware files
 197
 198 **--early-microcode**::
 199     Combine early microcode with ramdisk
 200
 201 **--no-early-microcode**::
 202     Do not combine early microcode with ramdisk
 203
 204 **--print-cmdline**::
 205     print the kernel command line for the current disk layout
 206
 207 **--mdadmconf**::
 208     include local _/etc/mdadm.conf_
 209
 210 **--nomdadmconf**::
 211     do not include local _/etc/mdadm.conf_
 212
 213 **--lvmconf**::
 214     include local _/etc/lvm/lvm.conf_
 215
 216 **--nolvmconf**::
 217     do not include local _/etc/lvm/lvm.conf_
 218
 219 **--fscks** [LIST]::
 220     add a space-separated list of fsck tools, in addition to _dracut.conf_'s
 221     specification; the installation is opportunistic (non-existing tools are
 222     ignored)
 223 +
 224 [NOTE]
 225 ===============================
 226 If [LIST] has multiple arguments, then you have to put these in quotes. For
 227 example:
 228 ----
 229 # dracut --fscks "fsck.foo barfsck"  ...
 230 ----
 231 ===============================
 232
 233 **--nofscks**::
 234     inhibit installation of any fsck tools
 235
 236 **--strip**::
 237     strip binaries in the initramfs (default)
 238
 239 **--nostrip**::
 240     do not strip binaries in the initramfs
 241
 242 **--prelink**::
 243     prelink binaries in the initramfs (default)
 244
 245 **--noprelink**::
 246     do not prelink binaries in the initramfs
 247
 248 **--hardlink**::
 249     hardlink files in the initramfs (default)
 250
 251 **--nohardlink**::
 252     do not hardlink files in the initramfs
 253
 254 **--prefix** _<dir>_::
 255     prefix initramfs files with the specified directory
 256
 257 **--noprefix**::
 258     do not prefix initramfs files (default)
 259
 260 **-h, --help**::
 261     display help text and exit.
 262
 263 **--debug**::
 264     output debug information of the build process
 265
 266 **-v, --verbose**::
 267     increase verbosity level (default is info(4))
 268
 269 **-q, --quiet**:: decrease verbosity level (default is info(4))
 270
 271 **-c, --conf** _<dracut configuration file>_::
 272     specify configuration file to use.
 273 +
 274 Default:
 275    _/etc/dracut.conf_
 276
 277 **--confdir** _<configuration directory>_::
 278     specify configuration directory to use.
 279 +
 280 Default:
 281    _/etc/dracut.conf.d_
 282
 283 **--tmpdir** _<temporary directory>_::
 284     specify temporary directory to use.
 285 +
 286 Default:
 287    _/var/tmp_
 288
 289 **--sshkey** _<sshkey file>_:: ssh key file used with ssh-client module.
 290
 291 **--logfile** _<logfile>_:: logfile to use; overrides any setting from
 292     the configuration files.
 293 +
 294 Default:
 295     _/var/log/dracut.log_
 296
 297 **-l, --local**::
 298     activates the local mode. dracut will use modules from the current working
 299     directory instead of the system-wide installed modules in
 300     _/usr/lib/dracut/modules.d_.
 301     This is useful when running dracut from a git checkout.
 302
 303 **-H, --hostonly**::
 304     Host-Only mode: Install only what is needed for booting the local host
 305     instead of a generic host and generate host-specific configuration.
 306 +
 307 [WARNING]
 308 ====
 309 If chrooted to another root other than the real root device, use "--fstab" and
 310 provide a valid _/etc/fstab_.
 311 ====
 312
 313 **-N, --no-hostonly**::
 314     Disable Host-Only mode
 315
 316 **--hostonly-cmdline**:
 317     Store kernel command line arguments needed in the initramfs
 318
 319 **--no-hostonly-cmdline**:
 320     Do not store kernel command line arguments needed in the initramfs
 321
 322 **--persistent-policy** _<policy>_::
 323     Use _<policy>_ to address disks and partitions.
 324     _<policy>_ can be any directory name found in /dev/disk.
 325     E.g. "by-uuid", "by-label"
 326
 327 **--fstab**::
 328     Use _/etc/fstab_ instead of _/proc/self/mountinfo_.
 329
 330 **--add-fstab** _<filename>_::
 331     Add entries of _<filename>_ to the initramfs /etc/fstab.
 332
 333 **--mount** "_<device>_ _<mountpoint>_ _<filesystem type>_ [_<filesystem options>_ [_<dump frequency>_ [_<fsck order>_]]]"::
 334     Mount _<device>_ on _<mountpoint>_ with _<filesystem type>_ in the
 335     initramfs. _<filesystem options>_, _<dump options>_ and _<fsck order>_ can
 336     be specified, see fstab manpage for the details.
 337     The default _<filesystem options>_ is "defaults".
 338     The default _<dump frequency>_ is "0".
 339     the default _<fsck order>_ is "2".
 340
 341 **--mount** "_<mountpoint>_"::
 342     Like above, but _<device>_, _<filesystem type>_ and _<filesystem options>_
 343     are determined by looking at the current mounts.
 344
 345 **--add-device** _<device>_ ::
 346     Bring up _<device>_ in initramfs, _<device>_ should be the device name.
 347     This can be useful in hostonly mode for resume support when your swap is on
 348     LVM or an encrypted partition.
 349     [NB --device can be used for compatibility with earlier releases]
 350
 351 **-i, --include** _<SOURCE>_ _<TARGET>_::
 352     include the files in the SOURCE directory into the
 353     TARGET directory in the final initramfs. If SOURCE is a file, it will be
 354     installed to TARGET in the final initramfs. This parameter can be specified
 355     multiple times.
 356
 357 **-I, --install** _<file list>_::
 358     install the space separated list of files into the initramfs.
 359 +
 360 [NOTE]
 361 ===============================
 362 If [LIST] has multiple arguments, then you have to put these in quotes. For
 363 example:
 364 ----
 365 # dracut --install "/bin/foo /sbin/bar"  ...
 366 ----
 367 ===============================
 368
 369 **--install-optional** _<file list>_::
 370     install the space separated list of files into the initramfs, if they exist.
 371
 372 **--gzip**::
 373     Compress the generated initramfs using gzip. This will be done by default,
 374     unless another compression option or --no-compress is passed. Equivalent to
 375     "--compress=gzip -9"
 376
 377 **--bzip2**::
 378     Compress the generated initramfs using bzip2.
 379 +
 380 [WARNING]
 381 ====
 382 Make sure your kernel has bzip2 decompression support compiled in, otherwise you
 383 will not be able to boot. Equivalent to "--compress=bzip2"
 384 ====
 385
 386 **--lzma**::
 387     Compress the generated initramfs using lzma.
 388 +
 389 [WARNING]
 390 ====
 391 Make sure your kernel has lzma decompression support compiled in, otherwise you
 392 will not be able to boot. Equivalent to "lzma --compress=lzma -9"
 393 ====
 394
 395 **--xz**::
 396     Compress the generated initramfs using xz.
 397 +
 398 [WARNING]
 399 ====
 400 Make sure your kernel has xz decompression support compiled in, otherwise you
 401 will not be able to boot. Equivalent to
 402 "lzma --compress=xz --check=crc32 --lzma2=dict=1MiB"
 403 ====
 404
 405 **--lzo**::
 406     Compress the generated initramfs using lzop.
 407 [WARNING]
 408 ====
 409 Make sure your kernel has lzo decompression support compiled in, otherwise you
 410 will not be able to boot.
 411 ====
 412
 413 **--lz4**::
 414     Compress the generated initramfs using lz4.
 415 [WARNING]
 416 ====
 417 Make sure your kernel has lz4 decompression support compiled in, otherwise you
 418 will not be able to boot.
 419 ====
 420
 421 **--compress** _<compressor>_::
 422     Compress the generated initramfs using the passed compression program. If
 423     you pass it just the name of a compression program, it will call that
 424     program with known-working arguments. If you pass a quoted string with
 425     arguments, it will be called with exactly those arguments. Depending on what
 426     you pass, this may result in an initramfs that the kernel cannot decompress.
 427
 428 **--no-compress**::
 429     Do not compress the generated initramfs. This will override any other
 430     compression options.
 431
 432 **--reproducible**::
 433     Create reproducible images.
 434
 435 **--no-reproducible**::
 436     Do not create reproducible images.
 437
 438 **--list-modules**::
 439     List all available dracut modules.
 440
 441 **-M, --show-modules**::
 442     Print included module's name to standard output during build.
 443
 444 **--keep**::
 445     Keep the initramfs temporary directory for debugging purposes.
 446
 447 **--printsize**::
 448     Print out the module install size
 449
 450 **--profile**:
 451     Output profile information of the build process
 452
 453 **--ro-mnt**:
 454     Mount / and /usr read-only by default.
 455
 456 **-L, --stdlog** _<level>_::
 457     [0-6] Specify logging level (to standard error)
 458 ----
 459           0 - suppress any messages
 460           1 - only fatal errors
 461           2 - all errors
 462           3 - warnings
 463           4 - info
 464           5 - debug info (here starts lots of output)
 465           6 - trace info (and even more)
 466 ----
 467
 468 **--regenerate-all**::
 469     Regenerate all initramfs images at the default location with the kernel
 470     versions found on the system. Additional parameters are passed through.
 471
 472 **--loginstall _<DIR>_**::
 473     Log all files installed from the host to _<DIR>_.
 474
 475 **--uefi**::
 476     Instead of creating an initramfs image, dracut will create an UEFI executable,
 477     which can be executed by an UEFI BIOS.
 478
 479 **--uefi-stub _<FILE>_**::
 480     Specifies the UEFI stub loader, which will load the attached kernel, initramfs and
 481     kernel command line and boots the kernel. The default is
 482     _/lib/systemd/boot/efi/linux<EFI-MACHINE-TYPE-NAME>.efi.stub_
 483     or _/usr/lib/gummiboot/linux<EFI-MACHINE-TYPE-NAME>.efi.stub_
 484
 485 **--kernel-image _<FILE>_**::
 486     Specifies the kernel image, which to include in the UEFI executable. The default is
 487     _/lib/modules/<KERNEL-VERSION>/vmlinuz_ or _/boot/vmlinuz-<KERNEL-VERSION>_
 488
 489 FILES
 490 -----
 491 _/var/log/dracut.log_::
 492     logfile of initramfs image creation
 493
 494 _/tmp/dracut.log_::
 495     logfile of initramfs image creation, if _/var/log/dracut.log_ is not
 496     writable
 497
 498 _/etc/dracut.conf_::
 499     see dracut.conf5
 500
 501 _/etc/dracut.conf.d/*.conf_::
 502     see dracut.conf5
 503
 504 _/usr/lib/dracut/dracut.conf.d/*.conf_::
 505     see dracut.conf5
 506
 507 Configuration in the initramfs
 508 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 509 _/etc/conf.d/_::
 510     Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
 511     set initial values. Command line options will override these values
 512     set in the configuration files.
 513
 514 _/etc/cmdline_::
 515     Can contain additional command line options. Deprecated, better use
 516     /etc/cmdline.d/*.conf.
 517
 518 _/etc/cmdline.d/*.conf_::
 519     Can contain additional command line options.
 520
 521 AVAILABILITY
 522 ------------
 523 The dracut command is part of the dracut package and is available from
 524 link:$$https://dracut.wiki.kernel.org$$[https://dracut.wiki.kernel.org]
 525
 526 AUTHORS
 527 -------
 528 Harald Hoyer
 529
 530 Victor Lowther
 531
 532 Philippe Seewer
 533
 534 Warren Togami
 535
 536 Amadeusz Żołnowski
 537
 538 Jeremy Katz
 539
 540 David Dillow
 541
 542 Will Woods
 543
 544 SEE ALSO
 545 --------
 546 *dracut.cmdline*(7) *dracut.conf*(5) *lsinitrd*(1)