dracut.cmdline.7.asc

   1 DRACUT.CMDLINE(7)
   2 =================
   3 :doctype: manpage
   4 :man source:   dracut
   5 :man manual:   dracut
   6
   7 NAME
   8 ----
   9 dracut.cmdline - dracut kernel command line options
  10
  11 DESCRIPTION
  12 -----------
  13 The root device used by the kernel is specified in the boot configuration
  14 file on the kernel command line, as always.
  15
  16 The traditional _root=/dev/sda1_ style device specification is allowed, but not
  17 encouraged. The root device should better be identified by LABEL or UUID. If a
  18 label is used, as in _root=LABEL=<label_of_root>_ the initramfs will search all
  19 available devices for a filesystem with the appropriate label, and mount that
  20 device as the root filesystem. _root=UUID=<uuidnumber>_ will mount the partition
  21 with that UUID as the root filesystem.
  22
  23 In the following all kernel command line parameters, which are processed by
  24 dracut, are described.
  25
  26 "rd.*" parameters mentioned without "=" are boolean parameters. They can be
  27 turned on/off by setting them to {0|1}. If the assignment with "=" is missing
  28 "=1" is implied. For example _rd.info_ can be turned off with _rd.info=0_ or
  29 turned on with _rd.info=1_ or _rd.info_. The last value in the kernel command
  30 line is the value, which is honored.
  31
  32 Standard
  33 ~~~~~~~~
  34 **init=**__<path to real init>__::
  35     specify the path to the init program to be started after the initramfs has
  36     finished
  37
  38 **root=**__<path to blockdevice>__::
  39     specify the block device to use as the root filesystem.
  40 +
  41 [listing]
  42 .Example
  43 --
  44 root=/dev/sda1
  45 root=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
  46 root=/dev/disk/by-label/Root
  47 root=LABEL=Root
  48 root=/dev/disk/by-uuid/3f5ad593-4546-4a94-a374-bcfb68aa11f7
  49 root=UUID=3f5ad593-4546-4a94-a374-bcfb68aa11f7
  50 root=PARTUUID=3f5ad593-4546-4a94-a374-bcfb68aa11f7
  51 --
  52
  53 **rootfstype=**__<filesystem type>__:: "auto" if not specified.
  54 +
  55 [listing]
  56 .Example
  57 --
  58 rootfstype=ext3
  59 --
  60
  61 **rootflags=**__<mount options>__::
  62     specify additional mount options for the root filesystem. If not set,
  63     _/etc/fstab_ of the real root will be parsed for special mount options and
  64     mounted accordingly.
  65
  66 **ro**::
  67     force mounting _/_ and _/usr_ (if it is a separate device) read-only.  If
  68     none of ro and rw is present, both are mounted according to _/etc/fstab_.
  69
  70 **rw**::
  71     force mounting _/_ and _/usr_ (if it is a separate device) read-write.
  72     See also ro option.
  73
  74 **rootfallback=**__<path to blockdevice>__::
  75     specify the block device to use as the root filesystem, if the normal root
  76     cannot be found. This can only be a simple block device with a simple file
  77     system, for which the filesystem driver is either compiled in, or added
  78     manually to the initramfs. This parameter can be specified multiple times.
  79
  80 **rd.auto** **rd.auto=1**::
  81     enable autoassembly of special devices like cryptoLUKS, dmraid, mdraid or
  82     lvm. Default is off as of dracut version >= 024.
  83
  84 **rd.hostonly=0**::
  85     removes all compiled in configuration of the host system the initramfs image
  86     was built on. This helps booting, if any disk layout changed, especially in
  87     combination with rd.auto or other parameters specifying the layout.
  88
  89 **rd.cmdline=ask**::
  90     prompts the user for additional kernel command line parameters
  91
  92 **rd.fstab=0**::
  93     do not honor special mount options for the root filesystem found in
  94     _/etc/fstab_ of the real root.
  95
  96 **resume=**__<path to resume partition>__::
  97     resume from a swap partition
  98 +
  99 [listing]
 100 .Example
 101 --
 102 resume=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
 103 resume=/dev/disk/by-uuid/3f5ad593-4546-4a94-a374-bcfb68aa11f7
 104 resume=UUID=3f5ad593-4546-4a94-a374-bcfb68aa11f7
 105 --
 106
 107 **rd.skipfsck**::
 108     skip fsck for rootfs and _/usr_.  If you're mounting _/usr_ read-only and
 109     the init system performs fsck before remount, you might want to use this
 110     option to avoid duplication.
 111
 112 iso-scan/filename
 113 ~~~~~~~~~~~~~~~~~
 114
 115 Using iso-scan/filename with a Fedora/Red Hat/CentOS Live iso should just work
 116 by copying the original kernel cmdline parameters.
 117
 118 [listing]
 119 .Example
 120 --
 121 menuentry 'Live Fedora 20' --class fedora --class gnu-linux --class gnu --class os {
 122     set isolabel=Fedora-Live-LXDE-x86_64-20-1
 123     set isofile="/boot/iso/Fedora-Live-LXDE-x86_64-20-1.iso"
 124     loopback loop $isofile
 125     linux (loop)/isolinux/vmlinuz0 boot=isolinux iso-scan/filename=$isofile root=live:LABEL=$isolabel ro rd.live.image quiet rhgb
 126     initrd (loop)/isolinux/initrd0.img
 127 }
 128 --
 129
 130 Misc
 131 ~~~~
 132 **rd.emergency=**__[reboot|poweroff|halt]__::
 133     specify, what action to execute in case of a critical failure. rd.shell=0 also
 134     be specified.
 135
 136 **rd.driver.blacklist=**__<drivername>__[,__<drivername>__,...]::
 137     do not load kernel module <drivername>. This parameter can be specified
 138     multiple times.
 139
 140 **rd.driver.pre=**__<drivername>__[,__<drivername>__,...]::
 141     force loading kernel module <drivername>. This parameter can be specified
 142     multiple times.
 143
 144 **rd.driver.post=**__<drivername>__[,__<drivername>__,...]::
 145     force loading kernel module <drivername> after all automatic loading modules
 146     have been loaded. This parameter can be specified multiple times.
 147
 148 **rd.retry=**__<seconds>__::
 149     specify how long dracut should retry the initqueue to configure devices.
 150     The default is 30 seconds. After 2/3 of the time, degraded raids are force
 151     started. If you have hardware, which takes a very long time to announce its
 152     drives, you might want to extend this value.
 153
 154 **rd.timeout=**__<seconds>__::
 155     specify how long dracut should wait for devices to appear. The
 156     default is '0', which means 'forever'. Note that this timeout
 157     should be longer than rd.retry to allow for proper configuration.
 158
 159 **rd.noverifyssl**::
 160     accept self-signed certificates for ssl downloads.
 161
 162 **rd.ctty=**__<terminal device>__::
 163    specify the controlling terminal for the console.
 164    This is useful, if you have multiple "console=" arguments.
 165
 166 [[dracutkerneldebug]]
 167 Debug
 168 ~~~~~
 169 If you are dropped to an emergency shell, the file
 170 _/run/initramfs/rdsosreport.txt_ is created, which can be saved to a (to be
 171 mounted by hand) partition (usually /boot) or a USB stick. Additional debugging
 172 info can be produced by adding **rd.debug** to the kernel command line.
 173 _/run/initramfs/rdsosreport.txt_ contains all logs and the output of some tools.
 174 It should be attached to any report about dracut problems.
 175
 176 **rd.info**::
 177     print informational output though "quiet" is set
 178
 179 **rd.shell**::
 180     allow dropping to a shell, if root mounting fails
 181
 182 **rd.debug**::
 183     set -x for the dracut shell.
 184     If systemd is active in the initramfs, all output is logged to the systemd
 185     journal, which you can inspect with "journalctl -ab".
 186     If systemd is not active, the logs are written to dmesg and
 187     _/run/initramfs/init.log_.
 188     If "quiet" is set, it also logs to the console.
 189
 190 **rd.memdebug=[0-4]**::
 191     Print memory usage info at various points, set the verbose level from 0 to 4.
 192 +
 193     Higher level means more debugging output:
 194 +
 195 ----
 196     0 - no output
 197     1 - partial /proc/meminfo
 198     2 - /proc/meminfo
 199     3 - /proc/meminfo + /proc/slabinfo
 200     4 - /proc/meminfo + /proc/slabinfo + tracekomem
 201         NOTE: tracekomem is a shell script utilizing kernel trace to track
 202               the rough total memory consumption of kernel modules during
 203               loading. It may override other trace configurations.
 204 ----
 205
 206 **rd.break**::
 207     drop to a shell at the end
 208
 209 **rd.break=**__{cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount|pre-pivot|cleanup}__::
 210     drop to a shell on defined breakpoint
 211
 212 **rd.udev.info**::
 213     set udev to loglevel info
 214
 215 **rd.udev.debug**::
 216     set udev to loglevel debug
 217
 218 I18N
 219 ~~~~
 220 **rd.vconsole.keymap=**__<keymap base file name>__::
 221     keyboard translation table loaded by loadkeys; taken from keymaps directory;
 222     will be written as KEYMAP to _/etc/vconsole.conf_ in the initramfs.
 223 +
 224 [listing]
 225 .Example
 226 --
 227 rd.vconsole.keymap=de-latin1-nodeadkeys
 228 --
 229
 230 **rd.vconsole.keymap.ext=**__<list of keymap base file names>__::
 231     list of extra keymaps to bo loaded (sep. by space); will be written as
 232     EXT_KEYMAP to _/etc/vconsole.conf_ in the initramfs
 233
 234 **rd.vconsole.unicode**::
 235     boolean, indicating UTF-8 mode; will be written as UNICODE to
 236     _/etc/vconsole.conf_ in the initramfs
 237
 238 **rd.vconsole.font=**__<font base file name>__::
 239     console font; taken from consolefonts directory; will be written as FONT to
 240     _/etc/vconsole.conf_ in the initramfs.
 241 +
 242 [listing]
 243 .Example
 244 --
 245 rd.vconsole.font=LatArCyrHeb-16
 246 --
 247
 248 **rd.vconsole.font.map=**__<console map base file name>__::
 249     see description of '-m' parameter in setfont manual; taken from consoletrans
 250     directory; will be written as FONT_MAP to _/etc/vconsole.conf_ in the
 251     initramfs
 252
 253 **rd.vconsole.font.unimap=**__<unicode table base file name>__::
 254     see description of '-u' parameter in setfont manual; taken from unimaps
 255     directory; will be written as FONT_UNIMAP to _/etc/vconsole.conf_ in the
 256     initramfs
 257
 258 **rd.locale.LANG=**__<locale>__::
 259     taken from the environment; if no UNICODE is defined we set its value in
 260     basis of LANG value (whether it ends with ".utf8" (or similar) or not); will
 261     be written as LANG to _/etc/locale.conf_ in the initramfs.
 262 +
 263 [listing]
 264 .Example
 265 --
 266 rd.locale.LANG=pl_PL.utf8
 267 --
 268
 269 **rd.locale.LC_ALL=**__<locale>__::
 270     taken from the environment; will be written as LC_ALL to _/etc/locale.conf_
 271     in the initramfs
 272
 273 LVM
 274 ~~~
 275 **rd.lvm=0**::
 276     disable LVM detection
 277
 278 **rd.lvm.vg=**__<volume group name>__::
 279     only activate the volume groups with the given name. rd.lvm.vg can be
 280     specified multiple times on the kernel command line.
 281
 282 **rd.lvm.lv=**__<logical volume name>__::
 283     only activate the logical volumes with the given name. rd.lvm.lv can be
 284     specified multiple times on the kernel command line.
 285
 286 **rd.lvm.conf=0**::
 287     remove any _/etc/lvm/lvm.conf_, which may exist in the initramfs
 288
 289 crypto LUKS
 290 ~~~~~~~~~~~
 291 **rd.luks=0**::
 292     disable crypto LUKS detection
 293
 294 **rd.luks.uuid=**__<luks uuid>__::
 295     only activate the LUKS partitions with the given UUID. Any "luks-" of the
 296     LUKS UUID is removed before comparing to _<luks uuid>_.
 297     The comparisons also matches, if _<luks uuid>_ is only the beginning of the
 298     LUKS UUID, so you don't have to specify the full UUID.
 299     This parameter can be specified multiple times.
 300
 301 **rd.luks.allow-discards=**__<luks uuid>__::
 302     Allow  using  of discards (TRIM) requests for LUKS partitions with the given
 303     UUID. Any "luks-" of the LUKS UUID is removed before comparing to
 304     _<luks uuid>_. The comparisons also matches, if _<luks uuid>_ is only the
 305     beginning of the LUKS UUID, so you don't have to specify the full UUID.
 306     This parameter can be specified multiple times.
 307
 308 **rd.luks.allow-discards**::
 309     Allow  using  of discards (TRIM) requests on all LUKS partitions.
 310
 311 **rd.luks.crypttab=0**::
 312     do not check, if LUKS partition is in _/etc/crypttab_
 313
 314 crypto LUKS - key on removable device support
 315 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 316 **rd.luks.key=**__<keypath>__:__<keydev>__:__<luksdev>__::
 317     _keypath_ is a path to key file to look for. It's REQUIRED. When _keypath_
 318     ends with '.gpg' it's considered to be key encrypted symmetrically with GPG.
 319     You will be prompted for password on boot. GPG support comes with
 320     'crypt-gpg' module which needs to be added explicitly.
 321 +
 322 _keydev_ is a device on which key file resides. It might be kernel name of
 323 devices (should start with "/dev/"), UUID (prefixed with "UUID=") or label
 324 (prefix with "LABEL="). You don't have to specify full UUID. Just its beginning
 325 will suffice, even if its ambiguous. All matching devices will be probed.
 326 This parameter is recommended, but not required. If not present, all block
 327 devices will be probed, which may significantly increase boot time.
 328 +
 329 If _luksdev_ is given, the specified key will only be applied for that LUKS
 330 device. Possible values are the same as for _keydev_. Unless you have several
 331 LUKS devices, you don't have to specify this parameter. The simplest usage is:
 332 +
 333 [listing]
 334 .Example
 335 --
 336 rd.luks.key=/foo/bar.key
 337 --
 338 +
 339 As you see, you can skip colons in such a case.
 340 +
 341 [NOTE]
 342 ===============================
 343 dracut pipes key to cryptsetup with _-d -_ argument, therefore you need to pipe
 344 to crypsetup luksFormat with _-d -_, too!
 345
 346 Here follows example for key encrypted with GPG:
 347
 348 [listing]
 349 --
 350 gpg --quiet --decrypt rootkey.gpg | \
 351 cryptsetup -d - -v --cipher serpent-cbc-essiv:sha256 \
 352 --key-size 256 luksFormat /dev/sda3
 353 --
 354
 355 If you use plain keys, just add path to _-d_ option:
 356
 357 [listing]
 358 --
 359 cryptsetup -d rootkey.key -v --cipher serpent-cbc-essiv:sha256 \
 360  --key-size 256 luksFormat /dev/sda3
 361 --
 362 ===============================
 363
 364 MD RAID
 365 ~~~~~~~
 366 **rd.md=0**::
 367     disable MD RAID detection
 368
 369 **rd.md.imsm=0**::
 370     disable MD RAID for imsm/isw raids, use DM RAID instead
 371
 372 **rd.md.ddf=0**::
 373     disable MD RAID for SNIA ddf raids, use DM RAID instead
 374
 375 **rd.md.conf=0**::
 376     ignore mdadm.conf included in initramfs
 377
 378 **rd.md.waitclean=1**::
 379     wait for any resync, recovery, or reshape activity to finish before
 380     continuing
 381
 382 **rd.md.uuid=**__<md raid uuid>__::
 383     only activate the raid sets with the given UUID. This parameter can be
 384     specified multiple times.
 385
 386 DM RAID
 387 ~~~~~~~
 388 **rd.dm=0**::
 389     disable DM RAID detection
 390
 391 **rd.dm.uuid=**__<dm raid uuid>__::
 392    only activate the raid sets with the given UUID. This parameter can be
 393    specified multiple times.
 394
 395 MULTIPATH
 396 ~~~~~~~~~
 397 **rd.multipath=0**::
 398    disable multipath detection
 399
 400 FIPS
 401 ~~~~
 402 **rd.fips**::
 403     enable FIPS
 404
 405 **boot=**__<boot device>__::
 406     specify the device, where /boot is located.
 407 +
 408 [listing]
 409 .Example
 410 --
 411 boot=/dev/sda1
 412 boot=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
 413 boot=UUID=<uuid>
 414 boot=LABEL=<label>
 415 --
 416
 417 **rd.fips.skipkernel**::
 418     skip checksum check of the kernel image. Useful, if the kernel image is not
 419     in a separate boot partition.
 420
 421 Network
 422 ~~~~~~~
 423
 424 [IMPORTANT]
 425 =====================
 426 It is recommended to either bind an interface to a MAC with the **ifname**
 427 argument, or to use the systemd-udevd predictable network interface names.
 428
 429 Predictable network interface device names based on:
 430
 431 - firmware/bios-provided index numbers for on-board devices
 432 - firmware-provided pci-express hotplug slot index number
 433 - physical/geographical location of the hardware
 434 - the interface's MAC address
 435
 436 See:
 437 http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames
 438
 439 Two character prefixes based on the type of interface:
 440
 441 en:: ethernet
 442 wl:: wlan
 443 ww:: wwan
 444
 445 Type of names:
 446
 447 o<index>:: on-board device index number
 448 s<slot>[f<function>][d<dev_id>]:: hotplug slot index number
 449 x<MAC>:: MAC address
 450 [P<domain>]p<bus>s<slot>[f<function>][d<dev_id>]:: PCI geographical location
 451 [P<domain>]p<bus>s<slot>[f<function>][u<port>][..][c<config>][i<interface>]:: USB port number chain
 452
 453 All multi-function PCI devices will carry the [f<function>] number in the
 454 device name, including the function 0 device.
 455
 456 When using PCI geography, The PCI domain is only prepended when it is not 0.
 457
 458 For USB devices the full chain of port numbers of hubs is composed. If the
 459 name gets longer than the maximum number of 15 characters, the name is not
 460 exported.
 461 The usual USB configuration == 1 and interface == 0 values are suppressed.
 462
 463 PCI ethernet card with firmware index "1"::
 464 * eno1
 465
 466 PCI ethernet card in hotplug slot with firmware index number::
 467 * ens1
 468
 469 PCI ethernet multi-function card with 2 ports::
 470 * enp2s0f0
 471 * enp2s0f1
 472
 473 PCI wlan card::
 474 * wlp3s0
 475
 476 USB built-in 3G modem::
 477 * wwp0s29u1u4i6
 478
 479 USB Android phone::
 480 * enp0s29u1u2
 481 =====================
 482
 483 **ip=**__{dhcp|on|any|dhcp6|auto6}__::
 484     dhcp|on|any::: get ip from dhcp server from all interfaces. If root=dhcp,
 485     loop sequentially through all interfaces (eth0, eth1, ...) and use the first
 486     with a valid DHCP root-path.
 487
 488     auto6::: IPv6 autoconfiguration
 489
 490     dhcp6::: IPv6 DHCP
 491
 492 **ip=**__<interface>__:__{dhcp|on|any|dhcp6|auto6}__[:[__<mtu>__][:__<macaddr>__]]::
 493     This parameter can be specified multiple times.
 494 +
 495 =====================
 496 dhcp|on|any|dhcp6::: get ip from dhcp server on a specific interface
 497 auto6::: do IPv6 autoconfiguration
 498 <macaddr>::: optionally **set** <macaddr> on the <interface>. This
 499 cannot be used in conjunction with the **ifname** argument for the
 500 same <interface>.
 501 =====================
 502
 503 **ip=**__<client-IP>__:[__<peer>__]:__<gateway-IP>__:__<netmask>__:__<client_hostname>__:__<interface>__:__{none|off|dhcp|on|any|dhcp6|auto6|ibft}__[:[__<mtu>__][:__<macaddr>__]]::
 504     explicit network configuration. If you want do define a IPv6 address, put it
 505     in brackets (e.g. [2001:DB8::1]). This parameter can be specified multiple
 506     times. __<peer>__ is optional and is the address of the remote endpoint
 507     for pointopoint interfaces and it may be followed by a slash and a decimal
 508     number, encoding the network prefix length.
 509 +
 510 =====================
 511 <macaddr>::: optionally **set** <macaddr> on the <interface>. This
 512 cannot be used in conjunction with the **ifname** argument for the
 513 same <interface>.
 514 =====================
 515
 516 **ip=**__<client-IP>__:[__<peer>__]:__<gateway-IP>__:__<netmask>__:__<client_hostname>__:__<interface>__:__{none|off|dhcp|on|any|dhcp6|auto6|ibft}__[:[__<dns1>__][:__<dns2>__]]::
 517     explicit network configuration. If you want do define a IPv6 address, put it
 518     in brackets (e.g. [2001:DB8::1]). This parameter can be specified multiple
 519     times. __<peer>__ is optional and is the address of the remote endpoint
 520     for pointopoint interfaces and it may be followed by a slash and a decimal
 521     number, encoding the network prefix length.
 522
 523 **ifname=**__<interface>__:__<MAC>__::
 524     Assign network device name <interface> (ie "bootnet") to the NIC with
 525     MAC <MAC>.
 526 +
 527 WARNING: Do **not** use the default kernel naming scheme for the interface name,
 528 as it can conflict with the kernel names. So, don't use "eth[0-9]+" for the
 529 interface name. Better name it "bootnet" or "bluesocket".
 530
 531 **rd.route=**__<net>__/__<netmask>__:__<gateway>__[:__<interface>__]::
 532     Add a static route with route options, which are separated by a colon.
 533     IPv6 addresses have to be put in brackets.
 534 +
 535 [listing]
 536 .Example
 537 --
 538     rd.route=192.168.200.0/24:192.168.100.222:ens10
 539     rd.route=192.168.200.0/24:192.168.100.222
 540     rd.route=192.168.200.0/24::ens10
 541     rd.route=[2001:DB8:3::/8]:[2001:DB8:2::1]:ens10
 542 --
 543
 544 **bootdev=**__<interface>__::
 545     specify network interface to use routing and netroot information from.
 546     Required if multiple ip= lines are used.
 547
 548 **BOOTIF=**__<MAC>__::
 549     specify network interface to use routing and netroot information from.
 550
 551 **rd.bootif=0**::
 552     Disable BOOTIF parsing, which is provided by PXE
 553
 554 **nameserver=**__<IP>__ [**nameserver=**__<IP>__ ...]::
 555     specify nameserver(s) to use
 556
 557 **rd.peerdns=0**::
 558     Disable DNS setting of DHCP parameters.
 559
 560 **biosdevname=0**::
 561     boolean, turn off biosdevname network interface renaming
 562
 563 **rd.neednet=1**::
 564     boolean, bring up network even without netroot set
 565
 566 **vlan=**__<vlanname>__:__<phydevice>__::
 567     Setup vlan device named <vlanname> on <phydeivce>.
 568     We support the four styles of vlan names: VLAN_PLUS_VID (vlan0005),
 569     VLAN_PLUS_VID_NO_PAD (vlan5), DEV_PLUS_VID (eth0.0005),
 570     DEV_PLUS_VID_NO_PAD (eth0.5)
 571
 572 **bond=**__<bondname>__[:__<bondslaves>__:[:__<options>__]]::
 573     Setup bonding device <bondname> on top of <bondslaves>.
 574     <bondslaves> is a comma-separated list of physical (ethernet) interfaces.
 575     <options> is a comma-separated list on bonding options (modinfo bonding for
 576     details) in format compatible with initscripts. If <options> includes
 577     multi-valued arp_ip_target option, then its values should be separated by
 578     semicolon. Bond without parameters assumes
 579     bond=bond0:eth0,eth1:mode=balance-rr
 580
 581 **team=**__<teammaster>__:__<teamslaves>__::
 582     Setup team device <teammaster> on top of <teamslaves>.
 583     <teamslaves> is a comma-separated list of physical (ethernet) interfaces.
 584
 585 **bridge=**__<bridgename>__:__<ethnames>__::
 586     Setup bridge <bridgename> with <ethnames>. <ethnames> is a comma-separated
 587     list of physical (ethernet) interfaces. Bridge without parameters assumes
 588     bridge=br0:eth0
 589
 590 NFS
 591 ~~~
 592 **root=**\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__]::
 593     mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given, use
 594     dhcp next_server. If server-ip is an IPv6 address it has to be put in
 595     brackets, e.g. [2001:DB8::1]. NFS options can be appended with the prefix
 596     ":" or "," and are seperated by ",".
 597
 598 **root=**nfs:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**nfs4:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**__{dhcp|dhcp6}__::
 599     root=dhcp alone directs initrd to look at the DHCP root-path where NFS
 600     options can be specified.
 601 +
 602 [listing]
 603 .Example
 604 --
 605     root-path=<server-ip>:<root-dir>[,<nfs-options>]
 606     root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
 607     root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
 608 --
 609
 610 **root=**_/dev/nfs_ nfsroot=\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__]::
 611     _Deprecated!_ kernel Documentation_/filesystems/nfsroot.txt_ defines this
 612     method. This is supported by dracut, but not recommended.
 613
 614 **rd.nfs.domain=**__<NFSv4 domain name>__::
 615     Set the NFSv4 domain name. Will override the settings in _/etc/idmap.conf_.
 616
 617 **rd.net.dhcp.retry=**__<cnt>__::
 618     If this option is set, dracut will try to connect via dhcp <cnt> times before failing.
 619     Default is 1.
 620
 621 **rd.net.timeout.dhcp=**__<arg>__::
 622     If this option is set, dhclient is called with "-timeout <arg>".
 623
 624 **rd.net.timeout.iflink=**__<seconds>__::
 625     Wait <seconds> until link shows up. Default is 60 seconds.
 626
 627 **rd.net.timeout.ifup=**__<seconds>__::
 628     Wait <seconds> until link has state "UP". Default is 20 seconds.
 629
 630 **rd.net.timeout.route=**__<seconds>__::
 631     Wait <seconds> until route shows up. Default is 20 seconds.
 632
 633 **rd.net.timeout.ipv6dad=**__<seconds>__::
 634     Wait <seconds> until IPv6 DAD is finished. Default is 50 seconds.
 635
 636 **rd.net.timeout.ipv6auto=**__<seconds>__::
 637     Wait <seconds> until IPv6 automatic addresses are assigned. Default is 40 seconds.
 638
 639 **rd.net.timeout.carrier=**__<seconds>__::
 640     Wait <seconds> until carrier is recognized. Default is 5 seconds.
 641
 642 CIFS
 643 ~~~
 644 **root=**cifs://[__<username>__[:__<password>__]@]__<server-ip>__:__<root-dir>__::
 645     mount cifs share from <server-ip>:/<root-dir>, if no server-ip is given, use
 646     dhcp next_server. if server-ip is an IPv6 address it has to be put in
 647     brackets, e.g. [2001:DB8::1]. If a username or password are not specified
 648 as part of the root, then they must be passed on the command line through
 649 cifsuser/cifspass.
 650 +
 651 WARNING: Passwords specified on the kernel command line are visible for all
 652 users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the
 653 network, when using DHCP with DHCP root-path.
 654
 655 **cifsuser**=__<username>__::
 656     Set the cifs username, if not specified as part of the root.
 657
 658 **cifspass**=__<password>__::
 659     Set the cifs password, if not specified as part of the root.
 660 +
 661 WARNING: Passwords specified on the kernel command line are visible for all
 662 users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the
 663 network, when using DHCP with DHCP root-path.
 664
 665 iSCSI
 666 ~~~~~
 667 **root=**iscsi:[__<username>__:__<password>__[:__<reverse>__:__<password>__]@][__<servername>__]:[__<protocol>__]:[__<port>__][:[__<iscsi_iface_name>__]:[__<netdev_name>__]]:[__<LUN>__]:__<targetname>__::
 668     protocol defaults to "6", LUN defaults to "0". If the "servername" field is
 669     provided by BOOTP or DHCP, then that field is used in conjunction with other
 670     associated fields to contact the boot server in the Boot stage. However, if
 671     the "servername" field is not provided, then the "targetname" field is then
 672     used in the Discovery Service stage in conjunction with other associated
 673     fields. See
 674     link:$$http://tools.ietf.org/html/rfc4173#section-5$$[rfc4173].
 675 +
 676 WARNING: Passwords specified on the kernel command line are visible for all
 677 users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the
 678 network, when using DHCP with DHCP root-path.
 679 +
 680 [listing]
 681 .Example
 682 --
 683 root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
 684 --
 685 +
 686 If servername is an IPv6 address, it has to be put in brackets:
 687 +
 688 [listing]
 689 .Example
 690 --
 691 root=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
 692 --
 693
 694 **root=**__???__ **netroot=**iscsi:[__<username>__:__<password>__[:__<reverse>__:__<password>__]@][__<servername>__]:[__<protocol>__]:[__<port>__][:[__<iscsi_iface_name>__]:[__<netdev_name>__]]:[__<LUN>__]:__<targetname>__ ...::
 695     multiple netroot options allow setting up multiple iscsi disks:
 696 +
 697 [listing]
 698 .Example
 699 --
 700 root=UUID=12424547
 701 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
 702 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target1
 703 --
 704 +
 705 If servername is an IPv6 address, it has to be put in brackets:
 706 +
 707 [listing]
 708 .Example
 709 --
 710 netroot=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
 711 --
 712 +
 713 WARNING: Passwords specified on the kernel command line are visible for all
 714 users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the
 715 network, when using DHCP with DHCP root-path.
 716 You may want to use rd.iscsi.firmware.
 717
 718 **root=**__???__ **rd.iscsi.initiator=**__<initiator>__ **rd.iscsi.target.name=**__<target name>__  **rd.iscsi.target.ip=**__<target ip>__ **rd.iscsi.target.port=**__<target port>__ **rd.iscsi.target.group=**__<target group>__ **rd.iscsi.username=**__<username>__ **rd.iscsi.password=**__<password>__ **rd.iscsi.in.username=**__<in username>__ **rd.iscsi.in.password=**__<in password>__::
 719     manually specify all iscsistart parameter (see **+iscsistart --help+**)
 720 +
 721 WARNING: Passwords specified on the kernel command line are visible for all
 722 users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the
 723 network, when using DHCP with DHCP root-path.
 724 You may want to use rd.iscsi.firmware.
 725
 726 **root=**_???_ **netroot=**iscsi **rd.iscsi.firmware=1**::
 727  will read the iscsi parameter from the BIOS firmware
 728
 729 **rd.iscsi.param=**__<param>__::
 730     <param> will be passed as "--param <param>" to iscsistart.
 731     This parameter can be specified multiple times.
 732 +
 733 [listing]
 734 .Example
 735 --
 736 "netroot=iscsi rd.iscsi.firmware=1 rd.iscsi.param=node.session.timeo.replacement_timeout=30"
 737 --
 738 +
 739 will result in
 740 +
 741 [listing]
 742 --
 743 iscsistart -b --param node.session.timeo.replacement_timeout=30
 744 --
 745
 746 **rd.iscsi.ibft** **rd.iscsi.ibft=1**:
 747     Turn on iBFT autoconfiguration for the interfaces
 748
 749 **rd.iscsi.waitnet=0**:
 750     Turn off waiting for all interfaces to be up before trying to login to the iSCSI targets.
 751
 752 **rd.iscsi.testroute=0**:
 753     Turn off checking, if the route to the iSCSI target IP is possible before trying to login.
 754
 755 FCoE
 756 ~~~~
 757 **fcoe=**__<edd|interface|MAC>__:__{dcb|nodcb}__::
 758     Try to connect to a FCoE SAN through the NIC specified by _<interface>_ or
 759     _<MAC>_ or EDD settings. For the second argument, currently only nodcb is
 760     supported. This parameter can be specified multiple times.
 761 +
 762 NOTE: letters in the MAC-address must be lowercase!
 763
 764 NBD
 765 ~~~
 766 **root=**??? **netroot=**nbd:__<server>__:__<port/exportname>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
 767     mount nbd share from <server>.
 768 +
 769 NOTE:
 770     If "exportname" instead of "port" is given the standard port is used.
 771     Newer versions of nbd are only supported with "exportname".
 772
 773 **root=dhcp** with **dhcp** **root-path=**nbd:__<server>__:__<port/exportname>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
 774     root=dhcp alone directs initrd to look at the DHCP root-path where NBD
 775     options can be specified. This syntax is only usable in cases where you are
 776     directly mounting the volume as the rootfs.
 777 +
 778 NOTE:
 779     If "exportname" instead of "port" is given the standard port is used.
 780     Newer versions of nbd are only supported with "exportname".
 781
 782 DASD
 783 ~~~~
 784 **rd.dasd=**....::
 785     same syntax as the kernel module parameter (s390 only)
 786
 787 ZFCP
 788 ~~~~
 789 **rd.zfcp=**__<zfcp adaptor device bus ID>__,__<WWPN>__,__<FCPLUN>__::
 790     rd.zfcp can be specified multiple times on the kernel command line.
 791 +
 792 [listing]
 793 .Example
 794 --
 795 rd.zfcp=0.0.4000,0x5005076300C213e9,0x5022000000000000
 796 --
 797
 798 **rd.zfcp.conf=0**::
 799     ignore zfcp.conf included in the initramfs
 800
 801 ZNET
 802 ~~~~
 803 **rd.znet=**__<nettype>__,__<subchannels>__,__<options>__::
 804     rd.znet can be specified multiple times on the kernel command line.
 805 +
 806 [listing]
 807 .Example
 808 --
 809 rd.znet=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,portname=foo
 810 rd.znet=ctc,0.0.0600,0.0.0601,protocol=bar
 811 --
 812
 813 Booting live images
 814 ~~~~~~~~~~~~~~~~~~~
 815 Dracut offers multiple options for live booted images:
 816
 817 =====================
 818 SquashFS with read-only filesystem image::: The system will boot with a read
 819 only filesystem from the SquashFS and apply a writable device-mapper snapshot
 820 over the read only filesystem.  Using this method ensures a relatively fast
 821 boot and lower RAM usage. Users **must be careful** to avoid writing too many
 822 blocks to the snapshot volume.  Once the blocks of the snapshot overlay are
 823 exhausted, the root filesystem becomes unusable and requires a reboot.  A
 824 persistent overlay is marked Invalid, and requires a difficult recovery.
 825 Non-persistent overlays default to 512 MiB in RAM, but the size can be adjusted
 826 with the **rd.live.overlay.size=** kernel command line option.
 827 +
 828 The filesystem structure is expected to be:
 829 +
 830 [listing]
 831 --
 832 squashfs.img          |  Squashfs from LiveCD .iso downloaded via network
 833    !(mount)
 834    /LiveOS
 835        |- ext3fs.img  |  Filesystem image to mount read-only
 836             !(mount)
 837             /bin      |  Live filesystem
 838             /boot     |
 839             /dev      |
 840             ...       |
 841 --
 842 +
 843 Dracut uses this method of live booting by default.  No additional command line
 844 options are required other than **root=live:<URL>** to specify the location
 845 of your squashed filesystem.
 846 +
 847 - The compressed SquashFS image can be copied during boot to RAM at
 848 `/run/initramfs/squashed.img` by using the **rd.live.ram=1** option.
 849 - A device with a persistent overlay can be booted read only by using the
 850 **rd.live.overlay.readonly** option on the kernel command line.  This will
 851 cause a temporary, writable overlay to be stacked over a read-only snapshot
 852 of the root filesystem.
 853 +
 854 Uncompressed live filesystem image:::
 855 When the live system was installed with the '--skipcompress' option of the
 856 __livecd-iso-to-disk__ installation script for Live USB devices, the root
 857 filesystem image, `ext3fs.img`, is expanded on installation and no SquashFS
 858 is involved during boot.
 859 +
 860 - If **rd.live.ram=1** is used in this situation, the full, uncompressed
 861 root filesystem is copied during boot to `/run/initramfs/rootfs.img` in the
 862 `/run` tmpfs.
 863 +
 864 - If **rd.live.overlay=none** is provided as a kernel command line option,
 865 a writable, linear device-mapper target is created on boot with no overlay.
 866
 867 writable filesystem image:::
 868 The system will retrieve a compressed filesystem image, extract it to
 869 `/run/initramfs/fsimg/rootfs.img`, connect it to a loop device, create a
 870 writable, linear device-mapper target at `/dev/mapper/live-rw`, and mount that
 871 as a writable volume at `/`.  More RAM is required during boot but the live
 872 filesystem is easier to manage if it becomes full.  Users can make a filesystem
 873 image of any size and that size will be maintained when the system boots. There
 874 is no persistence of root filesystem changes between boots with this option.
 875 +
 876 The filesystem structure is expected to be:
 877 +
 878 [listing]
 879 --
 880 rootfs.tgz            |  Compressed tarball containing fileystem image
 881    !(unpack)
 882    /rootfs.img        |  Filesystem image at /run/initramfs/fsimg/
 883       !(mount)
 884       /bin            |  Live filesystem
 885       /boot           |
 886       /dev            |
 887       ...             |
 888 --
 889 +
 890 To use this boot option, ensure that **rd.writable.fsimg=1** is in your kernel
 891 command line and add the **root=live:<URL>** to specify the location
 892 of your compressed filesystem image tarball or SquashFS image.
 893 =====================
 894
 895 **rd.writable.fsimg=**1::
 896 Enables writable filesystem support.  The system will boot with a fully
 897 writable (but non-persistent) filesystem without snapshots __(see notes above
 898 about available live boot options)__.  You can use the **rootflags** option to
 899 set mount options for the live filesystem as well __(see documentation about
 900 rootflags in the **Standard** section above)__.
 901 This implies that the whole image is copied to RAM before the boot continues.
 902 +
 903 NOTE: There must be enough free RAM available to hold the complete image.
 904 +
 905 This method is very suitable for diskless boots.
 906
 907 **root=**live:__<url>__::
 908 Boots a live image retrieved from __<url>__.  Valid handlers: __http, https, ftp, torrent, tftp__.
 909 +
 910 [listing]
 911 .Example
 912 --
 913 root=live:http://example.com/liveboot.img
 914 root=live:ftp://ftp.example.com/liveboot.img
 915 root=live:torrent://example.com/liveboot.img.torrent
 916 --
 917
 918 **rd.live.debug=**1::
 919 Enables debug output from the live boot process.
 920
 921 **rd.live.dir=**__<path>__::
 922 Specifies the directory within the squashfs where the ext3fs.img or rootfs.img
 923 can be found.  By default, this is __LiveOS__.
 924
 925 **rd.live.squashimg=**__<filename of SquashFS image>__::
 926 Specifies the filename for a SquashFS image of the root filesystem.
 927 By default, this is __squashfs.img__.
 928
 929 **rd.live.ram=**1::
 930 Copy the complete image to RAM and use this for booting. This is useful
 931 when the image resides on, i.e., a DVD which needs to be ejected later on.
 932
 933 **rd.live.overlay=**__<devspec>__:__(<pathspec>|auto)__|__none__::
 934 Allow the usage of a permanent overlay.
 935 - _<devspec>_ specifies the path to a device with a mountable filesystem.
 936 - _<pathspec>_ is the path to a file within that filesystem, which shall be
 937 used to persist the changes made to the device specified by the
 938 **root=live:__<url>__** option.
 939 - _none_ specifies no overlay when an uncompressed live root filesystem is
 940 available.
 941 +
 942 [listing]
 943 .Example
 944 --
 945 rd.live.overlay=/dev/sdb1:persistent-overlay.img
 946 --
 947
 948 **rd.live.overlay.size=**__<size_MiB>__::
 949 Specifies a non-persistent overlay size in MiB.  The default is _512_.
 950
 951 **rd.live.overlay.readonly=**1::
 952 Specifies a non-persistent, writable snapshot overlay to be stacked over a
 953 read-only snapshot of the root filesystem, `/dev/mapper/live-ro`.
 954
 955 **rd.live.overlay.reset=**1::
 956 Specifies that a persistent overlay should be reset on boot.  All root
 957 filesystem changes are vacated by this action.
 958
 959 **rd.live.overlay.thin=**1::
 960 Enables the usage of thin snapshots instead of classic dm snapshots.
 961 The advantage of thin snapshots is that they support discards, and will free
 962 blocks that are not claimed by the filesystem. In this use case, this means
 963 that memory is given back to the kernel when the filesystem does not claim it
 964 anymore.
 965
 966
 967 Plymouth Boot Splash
 968 ~~~~~~~~~~~~~~~~~~~~
 969 **plymouth.enable=0**::
 970     disable the plymouth bootsplash completely.
 971
 972 **rd.plymouth=0**::
 973     disable the plymouth bootsplash only for the initramfs.
 974
 975 Kernel keys
 976 ~~~~~~~~~~~
 977 **masterkey=**__<kernel master key path name>__::
 978     Set the path name of the kernel master key.
 979 +
 980 [listing]
 981 .Example
 982 --
 983 masterkey=/etc/keys/kmk-trusted.blob
 984 --
 985
 986 **masterkeytype=**__<kernel master key type>__::
 987     Set the type of the kernel master key.
 988 +
 989 [listing]
 990 .Example
 991 --
 992 masterkeytype=trusted
 993 --
 994
 995 **evmkey=**__<EVM key path name>__::
 996     Set the path name of the EVM key.
 997 +
 998 [listing]
 999 .Example
1000 --
1001 evmkey=/etc/keys/evm-trusted.blob
1002 --
1003
1004 **ecryptfskey=**__<eCryptfs key path name>__::
1005     Set the path name of the eCryptfs key.
1006 +
1007 [listing]
1008 .Example
1009 --
1010 ecryptfskey=/etc/keys/ecryptfs-trusted.blob
1011 --
1012
1013 Deprecated, renamed Options
1014 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
1015 Here is a list of options, which were used in dracut prior to version 008, and
1016 their new replacement.
1017
1018 rdbreak:: rd.break
1019
1020 rd_CCW:: rd.ccw
1021
1022 rd_DASD_MOD:: rd.dasd
1023
1024 rd_DASD:: rd.dasd
1025
1026 rdinitdebug rdnetdebug:: rd.debug
1027
1028 rd_NO_DM:: rd.dm=0
1029
1030 rd_DM_UUID:: rd.dm.uuid
1031
1032 rdblacklist:: rd.driver.blacklist
1033
1034 rdinsmodpost:: rd.driver.post
1035
1036 rdloaddriver:: rd.driver.pre
1037
1038 rd_NO_FSTAB:: rd.fstab=0
1039
1040 rdinfo:: rd.info
1041
1042 check:: rd.live.check
1043
1044 rdlivedebug:: rd.live.debug
1045
1046 live_dir:: rd.live.dir
1047
1048 liveimg:: rd.live.image
1049
1050 overlay:: rd.live.overlay
1051
1052 readonly_overlay:: rd.live.overlay.readonly
1053
1054 reset_overlay:: rd.live.overlay.reset
1055
1056 live_ram:: rd.live.ram
1057
1058 rd_NO_CRYPTTAB:: rd.luks.crypttab=0
1059
1060 rd_LUKS_KEYDEV_UUID:: rd.luks.keydev.uuid
1061
1062 rd_LUKS_KEYPATH:: rd.luks.keypath
1063
1064 rd_NO_LUKS:: rd.luks=0
1065
1066 rd_LUKS_UUID:: rd.luks.uuid
1067
1068 rd_NO_LVMCONF:: rd.lvm.conf
1069
1070 rd_LVM_LV:: rd.lvm.lv
1071
1072 rd_NO_LVM:: rd.lvm=0
1073
1074 rd_LVM_SNAPSHOT:: rd.lvm.snapshot
1075
1076 rd_LVM_SNAPSIZE:: rd.lvm.snapsize
1077
1078 rd_LVM_VG:: rd.lvm.vg
1079
1080 rd_NO_MDADMCONF:: rd.md.conf=0
1081
1082 rd_NO_MDIMSM:: rd.md.imsm=0
1083
1084 rd_NO_MD:: rd.md=0
1085
1086 rd_MD_UUID:: rd.md.uuid
1087
1088 rd_NO_MULTIPATH: rd.multipath=0
1089
1090 rd_NFS_DOMAIN:: rd.nfs.domain
1091
1092 iscsi_initiator:: rd.iscsi.initiator
1093
1094 iscsi_target_name:: rd.iscsi.target.name
1095
1096 iscsi_target_ip:: rd.iscsi.target.ip
1097
1098 iscsi_target_port:: rd.iscsi.target.port
1099
1100 iscsi_target_group:: rd.iscsi.target.group
1101
1102 iscsi_username:: rd.iscsi.username
1103
1104 iscsi_password:: rd.iscsi.password
1105
1106 iscsi_in_username:: rd.iscsi.in.username
1107
1108 iscsi_in_password:: rd.iscsi.in.password
1109
1110 iscsi_firmware:: rd.iscsi.firmware=0
1111
1112 rd_NO_PLYMOUTH:: rd.plymouth=0
1113
1114 rd_retry:: rd.retry
1115
1116 rdshell:: rd.shell
1117
1118 rd_NO_SPLASH:: rd.splash
1119
1120 rdudevdebug:: rd.udev.debug
1121
1122 rdudevinfo:: rd.udev.info
1123
1124 rd_NO_ZFCPCONF:: rd.zfcp.conf=0
1125
1126 rd_ZFCP:: rd.zfcp
1127
1128 rd_ZNET:: rd.znet
1129
1130 KEYMAP:: vconsole.keymap
1131
1132 KEYTABLE:: vconsole.keymap
1133
1134 SYSFONT:: vconsole.font
1135
1136 CONTRANS:: vconsole.font.map
1137
1138 UNIMAP:: vconsole.font.unimap
1139
1140 UNICODE:: vconsole.unicode
1141
1142 EXT_KEYMAP:: vconsole.keymap.ext
1143
1144 Configuration in the Initramfs
1145 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1146 _/etc/conf.d/_::
1147     Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
1148     set initial values. Command line options will override these values
1149     set in the configuration files.
1150
1151 _/etc/cmdline_::
1152     Can contain additional command line options. Deprecated, better use
1153     /etc/cmdline.d/*.conf.
1154
1155 _/etc/cmdline.d/*.conf_::
1156     Can contain additional command line options.
1157
1158 AUTHOR
1159 ------
1160 Harald Hoyer
1161
1162 SEE ALSO
1163 --------
1164 *dracut*(8) *dracut.conf*(5)