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 **--add-device** _<device>_ ::
 342     Bring up _<device>_ in initramfs, _<device>_ should be the device name.
 343     This can be useful in hostonly mode for resume support when your swap is on
 344     LVM or an encrypted partition.
 345     [NB --device can be used for compatibility with earlier releases]
 346
 347 **-i, --include** _<SOURCE>_ _<TARGET>_::
 348     include the files in the SOURCE directory into the
 349     TARGET directory in the final initramfs. If SOURCE is a file, it will be
 350     installed to TARGET in the final initramfs. This parameter can be specified
 351     multiple times.
 352
 353 **-I, --install** _<file list>_::
 354     install the space separated list of files into the initramfs.
 355 +
 356 [NOTE]
 357 ===============================
 358 If [LIST] has multiple arguments, then you have to put these in quotes. For
 359 example:
 360 ----
 361 # dracut --install "/bin/foo /sbin/bar"  ...
 362 ----
 363 ===============================
 364
 365 **--install-optional** _<file list>_::
 366     install the space separated list of files into the initramfs, if they exist.
 367
 368 **--gzip**::
 369     Compress the generated initramfs using gzip. This will be done by default,
 370     unless another compression option or --no-compress is passed. Equivalent to
 371     "--compress=gzip -9"
 372
 373 **--bzip2**::
 374     Compress the generated initramfs using bzip2.
 375 +
 376 [WARNING]
 377 ====
 378 Make sure your kernel has bzip2 decompression support compiled in, otherwise you
 379 will not be able to boot. Equivalent to "--compress=bzip2"
 380 ====
 381
 382 **--lzma**::
 383     Compress the generated initramfs using lzma.
 384 +
 385 [WARNING]
 386 ====
 387 Make sure your kernel has lzma decompression support compiled in, otherwise you
 388 will not be able to boot. Equivalent to "lzma --compress=lzma -9"
 389 ====
 390
 391 **--xz**::
 392     Compress the generated initramfs using xz.
 393 +
 394 [WARNING]
 395 ====
 396 Make sure your kernel has xz decompression support compiled in, otherwise you
 397 will not be able to boot. Equivalent to
 398 "lzma --compress=xz --check=crc32 --lzma2=dict=1MiB"
 399 ====
 400
 401 **--lzo**::
 402     Compress the generated initramfs using lzop.
 403 [WARNING]
 404 ====
 405 Make sure your kernel has lzo decompression support compiled in, otherwise you
 406 will not be able to boot.
 407 ====
 408
 409 **--lz4**::
 410     Compress the generated initramfs using lz4.
 411 [WARNING]
 412 ====
 413 Make sure your kernel has lz4 decompression support compiled in, otherwise you
 414 will not be able to boot.
 415 ====
 416
 417 **--compress** _<compressor>_::
 418     Compress the generated initramfs using the passed compression program. If
 419     you pass it just the name of a compression program, it will call that
 420     program with known-working arguments. If you pass a quoted string with
 421     arguments, it will be called with exactly those arguments. Depending on what
 422     you pass, this may result in an initramfs that the kernel cannot decompress.
 423
 424 **--no-compress**::
 425     Do not compress the generated initramfs. This will override any other
 426     compression options.
 427
 428 **--reproducible**::
 429     Create reproducible images.
 430
 431 **--list-modules**::
 432     List all available dracut modules.
 433
 434 **-M, --show-modules**::
 435     Print included module's name to standard output during build.
 436
 437 **--keep**::
 438     Keep the initramfs temporary directory for debugging purposes.
 439
 440 **--printsize**::
 441     Print out the module install size
 442
 443 **--profile**:
 444     Output profile information of the build process
 445
 446 **--ro-mnt**:
 447     Mount / and /usr read-only by default.
 448
 449 **-L, --stdlog** _<level>_::
 450     [0-6] Specify logging level (to standard error)
 451 ----
 452           0 - suppress any messages
 453           1 - only fatal errors
 454           2 - all errors
 455           3 - warnings
 456           4 - info
 457           5 - debug info (here starts lots of output)
 458           6 - trace info (and even more)
 459 ----
 460
 461 **--regenerate-all**::
 462     Regenerate all initramfs images at the default location with the kernel
 463     versions found on the system. Additional parameters are passed through.
 464
 465 **--loginstall _<DIR>_**::
 466     Log all files installed from the host to _<DIR>_.
 467
 468 **--uefi**::
 469     Instead of creating an initramfs image, dracut will create an UEFI executable,
 470     which can be executed by an UEFI BIOS.
 471
 472 **--uefi-stub _<FILE>_**::
 473     Specifies the UEFI stub loader, which will load the attached kernel, initramfs and
 474     kernel command line and boots the kernel. The default is
 475     _/lib/systemd/boot/efi/linux<EFI-MACHINE-TYPE-NAME>.efi.stub_
 476     or _/usr/lib/gummiboot/linux<EFI-MACHINE-TYPE-NAME>.efi.stub_
 477
 478 **--kernel-image _<FILE>_**::
 479     Specifies the kernel image, which to include in the UEFI executable. The default is
 480     _/lib/modules/<KERNEL-VERSION>/vmlinuz_ or _/boot/vmlinuz-<KERNEL-VERSION>_
 481
 482 FILES
 483 -----
 484 _/var/log/dracut.log_::
 485     logfile of initramfs image creation
 486
 487 _/tmp/dracut.log_::
 488     logfile of initramfs image creation, if _/var/log/dracut.log_ is not
 489     writable
 490
 491 _/etc/dracut.conf_::
 492     see dracut.conf5
 493
 494 _/etc/dracut.conf.d/*.conf_::
 495     see dracut.conf5
 496
 497 _/usr/lib/dracut/dracut.conf.d/*.conf_::
 498     see dracut.conf5
 499
 500 Configuration in the initramfs
 501 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 502 _/etc/conf.d/_::
 503     Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
 504     set initial values. Command line options will override these values
 505     set in the configuration files.
 506
 507 _/etc/cmdline_::
 508     Can contain additional command line options. Deprecated, better use
 509     /etc/cmdline.d/*.conf.
 510
 511 _/etc/cmdline.d/*.conf_::
 512     Can contain additional command line options.
 513
 514 AVAILABILITY
 515 ------------
 516 The dracut command is part of the dracut package and is available from
 517 link:$$https://dracut.wiki.kernel.org$$[https://dracut.wiki.kernel.org]
 518
 519 AUTHORS
 520 -------
 521 Harald Hoyer
 522
 523 Victor Lowther
 524
 525 Philippe Seewer
 526
 527 Warren Togami
 528
 529 Amadeusz Żołnowski
 530
 531 Jeremy Katz
 532
 533 David Dillow
 534
 535 Will Woods
 536
 537 SEE ALSO
 538 --------
 539 *dracut.cmdline*(7) *dracut.conf*(5) *lsinitrd*(1)