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 safed 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 **--omit-drivers** _<list of kernel modules>_::
 140     specify a space-separated list of kernel modules not to add to the
 141     initramfs.
 142     The kernel modules have to be specified without the ".ko" suffix. This
 143     parameter can be specified multiple times.
 144 +
 145 [NOTE]
 146 ===============================
 147 If [LIST] has multiple arguments, then you have to put these in quotes. For
 148 example:
 149 ----
 150 # dracut --omit-drivers "kmodule1 kmodule2"  ...
 151 ----
 152 ===============================
 153
 154 **--filesystems** _<list of filesystems>_::
 155     specify a space-separated list of kernel filesystem modules to exclusively
 156     include in the generic initramfs. This parameter can be specified multiple
 157     times.
 158 +
 159 [NOTE]
 160 ===============================
 161 If [LIST] has multiple arguments, then you have to put these in quotes. For
 162 example:
 163 ----
 164 # dracut --filesystems "filesystem1 filesystem2"  ...
 165 ----
 166 ===============================
 167
 168 **-k, --kmoddir** _<kernel directory>_::
 169     specify the directory, where to look for kernel modules
 170
 171 **--fwdir** _<dir>[:<dir>...]++_::
 172     specify additional directories, where to look for firmwares. This parameter
 173     can be specified multiple times.
 174
 175 **--kernel-cmdline <parameters>**::
 176     specify default kernel command line parameters
 177
 178
 179 **--kernel-only**::
 180     only install kernel drivers and firmware files
 181
 182 **--no-kernel**::
 183     do not install kernel drivers and firmware files
 184
 185 **--early-microcode**::
 186     Combine early microcode with ramdisk
 187
 188 **--no-early-microcode**::
 189     Do not combine early microcode with ramdisk
 190
 191 **--print-cmdline**::
 192     print the kernel command line for the current disk layout
 193
 194 **--mdadmconf**::
 195     include local _/etc/mdadm.conf_
 196
 197 **--nomdadmconf**::
 198     do not include local _/etc/mdadm.conf_
 199
 200 **--lvmconf**::
 201     include local _/etc/lvm/lvm.conf_
 202
 203 **--nolvmconf**::
 204     do not include local _/etc/lvm/lvm.conf_
 205
 206 **--fscks** [LIST]::
 207     add a space-separated list of fsck tools, in addition to _dracut.conf_'s
 208     specification; the installation is opportunistic (non-existing tools are
 209     ignored)
 210 +
 211 [NOTE]
 212 ===============================
 213 If [LIST] has multiple arguments, then you have to put these in quotes. For
 214 example:
 215 ----
 216 # dracut --fscks "fsck.foo barfsck"  ...
 217 ----
 218 ===============================
 219
 220 **--nofscks**::
 221     inhibit installation of any fsck tools
 222
 223 **--strip**::
 224     strip binaries in the initramfs (default)
 225
 226 **--nostrip**::
 227     do not strip binaries in the initramfs
 228
 229 **--prelink**::
 230     prelink binaries in the initramfs (default)
 231
 232 **--noprelink**::
 233     do not prelink binaries in the initramfs
 234
 235 **--hardlink**::
 236     hardlink files in the initramfs (default)
 237
 238 **--nohardlink**::
 239     do not hardlink files in the initramfs
 240
 241 **--prefix** _<dir>_::
 242     prefix initramfs files with the specified directory
 243
 244 **--noprefix**::
 245     do not prefix initramfs files (default)
 246
 247 **-h, --help**::
 248     display help text and exit.
 249
 250 **--debug**::
 251     output debug information of the build process
 252
 253 **-v, --verbose**::
 254     increase verbosity level (default is info(4))
 255
 256 **-q, --quiet**:: decrease verbosity level (default is info(4))
 257
 258 **-c, --conf** _<dracut configuration file>_::
 259     specify configuration file to use.
 260 +
 261 Default:
 262    _/etc/dracut.conf_
 263
 264 **--confdir** _<configuration directory>_::
 265     specify configuration directory to use.
 266 +
 267 Default:
 268    _/etc/dracut.conf.d_
 269
 270 **--tmpdir** _<temporary directory>_::
 271     specify temporary directory to use.
 272 +
 273 Default:
 274    _/var/tmp_
 275
 276 **--sshkey** _<sshkey file>_:: ssh key file used with ssh-client module.
 277
 278 **--logfile** _<logfile>_:: logfile to use; overrides any setting from
 279     the configuration files.
 280 +
 281 Default:
 282     _/var/log/dracut.log_
 283
 284 **-l, --local**::
 285     activates the local mode. dracut will use modules from the current working
 286     directory instead of the system-wide installed modules in
 287     _/usr/lib/dracut/modules.d_.
 288     This is useful when running dracut from a git checkout.
 289
 290 **-H, --hostonly**::
 291     Host-Only mode: Install only what is needed for booting the local host
 292     instead of a generic host and generate host-specific configuration.
 293 +
 294 [WARNING]
 295 ====
 296 If chrooted to another root other than the real root device, use "--fstab" and
 297 provide a valid _/etc/fstab_.
 298 ====
 299
 300 **-N, --no-hostonly**::
 301     Disable Host-Only mode
 302
 303 **--persistent-policy** _<policy>_::
 304     Use _<policy>_ to address disks and partitions.
 305     _<policy>_ can be any directory name found in /dev/disk.
 306     E.g. "by-uuid", "by-label"
 307
 308 **--fstab**::
 309     Use _/etc/fstab_ instead of _/proc/self/mountinfo_.
 310
 311 **--add-fstab** _<filename>_::
 312     Add entries of _<filename>_ to the initramfs /etc/fstab.
 313
 314 **--mount** "_<device>_ _<mountpoint>_ _<filesystem type>_ _<filesystem options>_"::
 315     Mount _<device>_ on _<mountpoint>_ with _<filesystem type>_ and _<filesystem
 316     options>_ in the initramfs
 317
 318 **--add-device** _<device>_ ::
 319     Bring up _<device>_ in initramfs, _<device>_ should be the device name.
 320     This can be useful in hostonly mode for resume support when your swap is on
 321     LVM or an encrypted partition.
 322     [NB --device can be used for compatibility with earlier releases]
 323
 324 **-i, --include** _<SOURCE>_ _<TARGET>_::
 325     include the files in the SOURCE directory into the
 326     TARGET directory in the final initramfs. If SOURCE is a file, it will be
 327     installed to TARGET in the final initramfs. This parameter can be specified
 328     multiple times.
 329
 330 **-I, --install** _<file list>_::
 331     install the space separated list of files into the initramfs.
 332 +
 333 [NOTE]
 334 ===============================
 335 If [LIST] has multiple arguments, then you have to put these in quotes. For
 336 example:
 337 ----
 338 # dracut --install "/bin/foo /sbin/bar"  ...
 339 ----
 340 ===============================
 341
 342 **--gzip**::
 343     Compress the generated initramfs using gzip. This will be done by default,
 344     unless another compression option or --no-compress is passed. Equivalent to
 345     "--compress=gzip -9"
 346
 347 **--bzip2**::
 348     Compress the generated initramfs using bzip2.
 349 +
 350 [WARNING]
 351 ====
 352 Make sure your kernel has bzip2 decompression support compiled in, otherwise you
 353 will not be able to boot. Equivalent to "--compress=bzip2"
 354 ====
 355
 356 **--lzma**::
 357     Compress the generated initramfs using lzma.
 358 +
 359 [WARNING]
 360 ====
 361 Make sure your kernel has lzma decompression support compiled in, otherwise you
 362 will not be able to boot. Equivalent to "lzma --compress=lzma -9"
 363 ====
 364
 365 **--xz**::
 366     Compress the generated initramfs using xz.
 367 +
 368 [WARNING]
 369 ====
 370 Make sure your kernel has xz decompression support compiled in, otherwise you
 371 will not be able to boot. Equivalent to
 372 "lzma --compress=xz --check=crc32 --lzma2=dict=1MiB"
 373 ====
 374
 375 **--lzo**::
 376     Compress the generated initramfs using lzop.
 377 [WARNING]
 378 ====
 379 Make sure your kernel has lzo decompression support compiled in, otherwise you
 380 will not be able to boot.
 381 ====
 382
 383 **--lz4**::
 384     Compress the generated initramfs using lz4.
 385 [WARNING]
 386 ====
 387 Make sure your kernel has lz4 decompression support compiled in, otherwise you
 388 will not be able to boot.
 389 ====
 390
 391 **--compress** _<compressor>_::
 392     Compress the generated initramfs using the passed compression program. If
 393     you pass it just the name of a compression program, it will call that
 394     program with known-working arguments. If you pass a quoted string with
 395     arguments, it will be called with exactly those arguments. Depending on what
 396     you pass, this may result in an initramfs that the kernel cannot decompress.
 397
 398 **--no-compress**::
 399     Do not compress the generated initramfs. This will override any other
 400     compression options.
 401
 402 **--list-modules**::
 403     List all available dracut modules.
 404
 405 **-M, --show-modules**::
 406     Print included module's name to standard output during build.
 407
 408 **--keep**::
 409     Keep the initramfs temporary directory for debugging purposes.
 410
 411 **--printsize**::
 412     Print out the module install size
 413
 414 **--profile**:
 415     Output profile information of the build process
 416
 417 **--ro-mnt**:
 418     Mount / and /usr read-only by default.
 419
 420 **-L, --stdlog** _<level>_::
 421     [0-6] Specify logging level (to standard error)
 422 ----
 423           0 - suppress any messages
 424           1 - only fatal errors
 425           2 - all errors
 426           3 - warnings
 427           4 - info
 428           5 - debug info (here starts lots of output)
 429           6 - trace info (and even more)
 430 ----
 431
 432 **--regenerate-all**::
 433     Regenerate all initramfs images at the default location with the kernel
 434     versions found on the system. Additional parameters are passed through.
 435
 436 FILES
 437 -----
 438 _/var/log/dracut.log_::
 439     logfile of initramfs image creation
 440
 441 _/tmp/dracut.log_::
 442     logfile of initramfs image creation, if _/var/log/dracut.log_ is not
 443     writable
 444
 445 _/etc/dracut.conf_::
 446     see dracut.conf5
 447
 448 _/etc/dracut.conf.d/*.conf_::
 449     see dracut.conf5
 450
 451 _/usr/lib/dracut/dracut.conf.d/*.conf_::
 452     see dracut.conf5
 453
 454 Configuration in the initramfs
 455 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 456 _/etc/conf.d/_::
 457     Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
 458     set initial values. Command line options will override these values
 459     set in the configuration files.
 460
 461 _/etc/cmdline_::
 462     Can contain additional command line options. Deprecated, better use
 463     /etc/cmdline.d/*.conf.
 464
 465 _/etc/cmdline.d/*.conf_::
 466     Can contain additional command line options.
 467
 468 AVAILABILITY
 469 ------------
 470 The dracut command is part of the dracut package and is available from
 471 link:$$https://dracut.wiki.kernel.org$$[https://dracut.wiki.kernel.org]
 472
 473 AUTHORS
 474 -------
 475 Harald Hoyer
 476
 477 Victor Lowther
 478
 479 Philippe Seewer
 480
 481 Warren Togami
 482
 483 Amadeusz Żołnowski
 484
 485 Jeremy Katz
 486
 487 David Dillow
 488
 489 Will Woods
 490
 491 SEE ALSO
 492 --------
 493 *dracut.cmdline*(7) *dracut.conf*(5)