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 programm 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 cannot be found.
  76     This can only be a simple block device with a simple file system, for which the filesystem
  77     driver is either compiled in, or added manually to the initramfs.
  78     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 lvm.
  82     Default is off as of dracut version >= 024.
  83
  84 **rd.fstab=0**::
  85     do not honor special mount options for the root filesystem found in
  86     _/etc/fstab_ of the real root.
  87
  88 **resume=**__<path to resume partition>__::
  89     resume from a swap partition
  90 +
  91 [listing]
  92 .Example
  93 --
  94 resume=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
  95 resume=/dev/disk/by-uuid/3f5ad593-4546-4a94-a374-bcfb68aa11f7
  96 resume=UUID=3f5ad593-4546-4a94-a374-bcfb68aa11f7
  97 --
  98
  99 **rd.skipfsck**::
 100     skip fsck for rootfs and _/usr_.  If you're mounting _/usr_ read-only and
 101     the init system performs fsck before remount, you might want to use this
 102     option to avoid duplication.
 103
 104
 105 Misc
 106 ~~~~
 107 **rd.driver.blacklist=**__<drivername>__[,__<drivername>__,...]::
 108     do not load kernel module <drivername>. This parameter can be specified
 109     multiple times.
 110
 111 **rd.driver.pre=**__<drivername>__[,__<drivername>__,...]::
 112     force loading kernel module <drivername>. This parameter can be specified
 113     multiple times.
 114
 115 **rd.driver.post=**__<drivername>__[,__<drivername>__,...]::
 116     force loading kernel module <drivername> after all automatic loading modules
 117     have been loaded. This parameter can be specified multiple times.
 118
 119 **rd.retry=**__<seconds>__::
 120     specify how long dracut should wait for devices to appear.
 121     The default is 30 seconds. After 2/3 of the time, degraded raids are force
 122     started. If you have hardware, which takes a very long time to announce its
 123     drives, you might want to extend this value.
 124
 125 **rd.noverifyssl**::
 126     accept self-signed certificates for ssl downloads.
 127
 128 **rd.ctty=**__<terminal device>__::
 129    specify the controlling terminal for the console.
 130    This is useful, if you have multiple "console=" arguments.
 131
 132 [[dracutkerneldebug]]
 133 Debug
 134 ~~~~~
 135 If you are dropped to an emergency shell, the file _/run/initramfs/rdsosreport.txt_ is created,
 136 which can be safed to a (to be mounted by hand) partition (usually /boot) or a USB stick.
 137 Additional debugging info can be produced by adding **rd.debug** to the kernel command line.
 138 _/run/initramfs/rdsosreport.txt_ contains all logs and the output of some tools.
 139 It should be attached to any report about dracut problems.
 140
 141 **rd.info**::
 142     print informational output though "quiet" is set
 143
 144 **rd.shell**::
 145     allow dropping to a shell, if root mounting fails
 146
 147 **rd.debug**::
 148     set -x for the dracut shell.
 149     If systemd is active in the initramfs, all output is logged to the systemd journal,
 150     which you can inspect with "journalctl -ab".
 151     If systemd is not active, the logs are written to dmesg and _/run/initramfs/init.log_.
 152     If "quiet" is set, it also logs to the console.
 153
 154 **rd.memdebug=[0-3]**::
 155     Print memory usage info at various points, set the verbose level from 0 to 3. +
 156     Higher level means more debugging output:
 157 +
 158 ----
 159     0 - no output
 160     1 - partial /proc/meminfo
 161     2 - /proc/meminfo
 162     3 - /proc/meminfo + /proc/slabinfo
 163 ----
 164
 165 **rd.break**::
 166     drop to a shell at the end
 167
 168 **rd.break=**__{cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount|pre-pivot|cleanup}__::
 169     drop to a shell on defined breakpoint
 170
 171 **rd.udev.info**::
 172     set udev to loglevel info
 173
 174 **rd.udev.debug**::
 175     set udev to loglevel debug
 176
 177 I18N
 178 ~~~~
 179 **rd.vconsole.keymap=**__<keymap base file name>__::
 180     keyboard translation table loaded by loadkeys; taken from keymaps directory;
 181     will be written as KEYMAP to _/etc/vconsole.conf_ in the initramfs.
 182 +
 183 [listing]
 184 .Example
 185 --
 186 rd.vconsole.keymap=de-latin1-nodeadkeys
 187 --
 188
 189 **rd.vconsole.keymap.ext=**__<list of keymap base file names>__::
 190     list of extra keymaps to bo loaded (sep. by space); will be written as
 191     EXT_KEYMAP to _/etc/vconsole.conf_ in the initramfs
 192
 193 **rd.vconsole.unicode**::
 194     boolean, indicating UTF-8 mode; will be written as UNICODE to
 195     _/etc/vconsole.conf_ in the initramfs
 196
 197 **rd.vconsole.font=**__<font base file name>__::
 198     console font; taken from consolefonts directory; will be written as FONT to
 199     _/etc/vconsole.conf_ in the initramfs.
 200 +
 201 [listing]
 202 .Example
 203 --
 204 rd.vconsole.font=LatArCyrHeb-16
 205 --
 206
 207 **rd.vconsole.font.map=**__<console map base file name>__::
 208     see description of '-m' parameter in setfont manual; taken from consoletrans
 209     directory; will be written as FONT_MAP to _/etc/vconsole.conf_ in the
 210     initramfs
 211
 212 **rd.vconsole.font.unimap=**__<unicode table base file name>__::
 213     see description of '-u' parameter in setfont manual; taken from unimaps
 214     directory; will be written as FONT_UNIMAP to _/etc/vconsole.conf_ in the
 215     initramfs
 216
 217 **rd.locale.LANG=**__<locale>__::
 218     taken from the environment; if no UNICODE is defined we set its value in
 219     basis of LANG value (whether it ends with ".utf8" (or similar) or not); will
 220     be written as LANG to _/etc/locale.conf_ in the initramfs.
 221 +
 222 [listing]
 223 .Example
 224 --
 225 rd.locale.LANG=pl_PL.utf8
 226 --
 227
 228 **rd.locale.LC_ALL=**__<locale>__::
 229     taken from the environment; will be written as LC_ALL to _/etc/locale.conf_
 230     in the initramfs
 231
 232 LVM
 233 ~~~
 234 **rd.lvm=0**::
 235     disable LVM detection
 236
 237 **rd.lvm.vg=**__<volume group name>__::
 238     only activate the volume groups with the given name. rd.lvm.vg can be
 239     specified multiple times on the kernel command line.
 240
 241 **rd.lvm.lv=**__<logical volume name>__::
 242     only activate the logical volumes with the given name. rd.lvm.lv can be
 243     specified multiple times on the kernel command line.
 244
 245 **rd.lvm.conf=0**::
 246     remove any _/etc/lvm/lvm.conf_, which may exist in the initramfs
 247
 248 crypto LUKS
 249 ~~~~~~~~~~~
 250 **rd.luks=0**::
 251     disable crypto LUKS detection
 252
 253 **rd.luks.uuid=**__<luks uuid>__::
 254     only activate the LUKS partitions with the given UUID. Any "luks-" of the
 255     LUKS UUID is removed before comparing to _<luks uuid>_.
 256     The comparisons also matches, if _<luks uuid>_ is only the beginning of the
 257     LUKS UUID, so you don't have to specify the full UUID.
 258     This parameter can be specified multiple times.
 259
 260 **rd.luks.allow-discards=**__<luks uuid>__::
 261     Allow  using  of discards (TRIM) requests for LUKS partitions with the given UUID.
 262     Any "luks-" of the LUKS UUID is removed before comparing to _<luks uuid>_.
 263     The comparisons also matches, if _<luks uuid>_ is only the beginning of the
 264     LUKS UUID, so you don't have to specify the full UUID.
 265     This parameter can be specified multiple times.
 266
 267 **rd.luks.allow-discards**::
 268     Allow  using  of discards (TRIM) requests on all LUKS partitions.
 269
 270 **rd.luks.crypttab=0**::
 271     do not check, if LUKS partition is in _/etc/crypttab_
 272
 273 crypto LUKS - key on removable device support
 274 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 275 **rd.luks.key=**__<keypath>__:__<keydev>__:__<luksdev>__::
 276     _keypath_ is a path to key file to look for. It's REQUIRED. When _keypath_ ends with '.gpg' it's considered to be key encrypted symmetrically with GPG. You will be prompted for password on boot. GPG support comes with 'crypt-gpg' module which needs to be added explicitly.
 277 +
 278 _keydev_ is a device on which key file resides. It might be kernel name of devices (should start with "/dev/"), UUID (prefixed with "UUID=") or label (prefix with "LABEL="). You don't have to specify full UUID. Just its beginning will suffice, even if its ambiguous. All matching devices will be probed. This parameter is recommended, but not required. If not present, all block devices will be probed, which may significantly increase boot time.
 279 +
 280 If _luksdev_ is given, the specified key will only be applied for that LUKS device. Possible values are the same as for _keydev_. Unless you have several LUKS devices, you don't have to specify this parameter. The simplest usage is:
 281 +
 282 [listing]
 283 .Example
 284 --
 285 rd.luks.key=/foo/bar.key
 286 --
 287 +
 288 As you see, you can skip colons in such a case.
 289 +
 290 [NOTE]
 291 ===============================
 292 dracut pipes key to cryptsetup with _-d -_ argument, therefore you need to pipe
 293 to crypsetup luksFormat with _-d -_, too!
 294
 295 Here follows example for key encrypted with GPG:
 296
 297 [listing]
 298 --
 299 gpg --quiet --decrypt rootkey.gpg | \
 300 cryptsetup -d - -v --cipher serpent-cbc-essiv:sha256 \
 301 --key-size 256 luksFormat /dev/sda3
 302 --
 303
 304 If you use plain keys, just add path to _-d_ option:
 305
 306 [listing]
 307 --
 308 cryptsetup -d rootkey.key -v --cipher serpent-cbc-essiv:sha256 \
 309  --key-size 256 luksFormat /dev/sda3
 310 --
 311 ===============================
 312
 313 MD RAID
 314 ~~~~~~~
 315 **rd.md=0**::
 316     disable MD RAID detection
 317
 318 **rd.md.imsm=0**::
 319     disable MD RAID for imsm/isw raids, use DM RAID instead
 320
 321 **rd.md.ddf=0**::
 322     disable MD RAID for SNIA ddf raids, use DM RAID instead
 323
 324 **rd.md.conf=0**::
 325     ignore mdadm.conf included in initramfs
 326
 327 **rd.md.waitclean=1**::
 328     wait for any resync, recovery, or reshape activity to finish before continuing
 329
 330 **rd.md.uuid=**__<md raid uuid>__::
 331     only activate the raid sets with the given UUID. This parameter can be
 332     specified multiple times.
 333
 334 DM RAID
 335 ~~~~~~~
 336 **rd.dm=0**::
 337     disable DM RAID detection
 338
 339 **rd.dm.uuid=**__<dm raid uuid>__::
 340    only activate the raid sets with the given UUID. This parameter can be
 341    specified multiple times.
 342
 343 FIPS
 344 ~~~~
 345 **rd.fips**::
 346     enable FIPS
 347
 348 **boot=**__<boot device>__::
 349     specify the device, where /boot is located.
 350 +
 351 [listing]
 352 .Example
 353 --
 354 boot=/dev/sda1
 355 boot=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
 356 boot=UUID=<uuid>
 357 boot=LABEL=<label>
 358 --
 359
 360 **rd.fips.skipkernel**::
 361     skip checksum check of the kernel image. Useful, if the kernel image is not
 362     in a separate boot partition.
 363
 364 Network
 365 ~~~~~~~
 366
 367 [IMPORTANT]
 368 =====================
 369 It is recommended to either bind an interface to a MAC with the **ifname** argument,
 370 or to use the systemd-udevd predictable network interface names.
 371
 372 Predictable network interface device names based on:
 373
 374 - firmware/bios-provided index numbers for on-board devices
 375 - firmware-provided pci-express hotplug slot index number
 376 - physical/geographical location of the hardware
 377 - the interface's MAC address
 378
 379 See: http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames
 380
 381 Two character prefixes based on the type of interface:
 382
 383 en:: ethernet
 384 wl:: wlan
 385 ww:: wwan
 386
 387 Type of names:
 388
 389 o<index>:: on-board device index number
 390 s<slot>[f<function>][d<dev_id>]:: hotplug slot index number
 391 x<MAC>:: MAC address
 392 [P<domain>]p<bus>s<slot>[f<function>][d<dev_id>]:: PCI geographical location
 393 [P<domain>]p<bus>s<slot>[f<function>][u<port>][..][c<config>][i<interface>]:: USB port number chain
 394
 395 All multi-function PCI devices will carry the [f<function>] number in the
 396 device name, including the function 0 device.
 397
 398 When using PCI geography, The PCI domain is only prepended when it is not 0.
 399
 400 For USB devices the full chain of port numbers of hubs is composed. If the
 401 name gets longer than the maximum number of 15 characters, the name is not
 402 exported.
 403 The usual USB configuration == 1 and interface == 0 values are suppressed.
 404
 405 PCI ethernet card with firmware index "1"::
 406 * eno1
 407
 408 PCI ethernet card in hotplug slot with firmware index number::
 409 * ens1
 410
 411 PCI ethernet multi-function card with 2 ports::
 412 * enp2s0f0
 413 * enp2s0f1
 414
 415 PCI wlan card::
 416 * wlp3s0
 417
 418 USB built-in 3G modem::
 419 * wwp0s29u1u4i6
 420
 421 USB Android phone::
 422 * enp0s29u1u2
 423 =====================
 424
 425 **ip=**__{dhcp|on|any|dhcp6|auto6|ibft}__::
 426     dhcp|on|any::: get ip from dhcp server from all interfaces. If root=dhcp, loop
 427     sequentially through all interfaces (eth0, eth1, ...) and use the first with
 428     a valid DHCP root-path.
 429
 430     auto6::: IPv6 autoconfiguration
 431
 432     dhcp6::: IPv6 DHCP
 433
 434     ibft::: iBFT autoconfiguration
 435
 436 **ip=**__<interface>__:__{dhcp|on|any|dhcp6|auto6}__[:[__<mtu>__][:__<macaddr>__]]::
 437     This parameter can be specified multiple times.
 438 +
 439 =====================
 440 dhcp|on|any|dhcp6::: get ip from dhcp server on a specific interface
 441 auto6::: do IPv6 autoconfiguration
 442 <macaddr>::: optionally **set** <macaddr> on the <interface>. This
 443 cannot be used in conjunction with the **ifname** argument for the
 444 same <interface>.
 445 =====================
 446
 447 **ip=**__<client-IP>__:__<server-IP>__:__<gateway-IP>__:__<netmask>__:__<client_hostname>__:__<interface>__:__{none|off|dhcp|on|any|dhcp6|auto6|ibft}__:[:[__<mtu>__][:__<macaddr>__]]::
 448     explicit network configuration. If you want do define a IPv6 address, put it
 449     in brackets (e.g. [2001:DB8::1]). This parameter can be specified multiple
 450     times.
 451 +
 452 =====================
 453 <macaddr>::: optionally **set** <macaddr> on the <interface>. This
 454 cannot be used in conjunction with the **ifname** argument for the
 455 same <interface>.
 456 =====================
 457
 458 **ifname=**__<interface>__:__<MAC>__::
 459     Assign network device name <interface> (ie "bootnet") to the NIC with MAC <MAC>.
 460 +
 461 WARNING: Do **not** use the default kernel naming scheme for the interface name,
 462 as it can conflict with the kernel names. So, don't use "eth[0-9]+" for the
 463 interface name. Better name it "bootnet" or "bluesocket".
 464
 465 **bootdev=**__<interface>__::
 466     specify network interface to use routing and netroot information from.
 467     Required if multiple ip= lines are used.
 468
 469 **nameserver=**__<IP>__ [**nameserver=**__<IP>__ ...]::
 470     specify nameserver(s) to use
 471
 472 **biosdevname=0**::
 473     boolean, turn off biosdevname network interface renaming
 474
 475 **rd.neednet=1**::
 476     boolean, bring up network even without netroot set
 477
 478 **vlan=**__<vlanname>__:__<phydevice>__::
 479     Setup vlan device named <vlanname> on <phydeivce>.
 480     We support the four styles of vlan names: VLAN_PLUS_VID (vlan0005), VLAN_PLUS_VID_NO_PAD (vlan5),
 481     DEV_PLUS_VID (eth0.0005), DEV_PLUS_VID_NO_PAD (eth0.5)
 482
 483 **bond=**__<bondname>__[:__<bondslaves>__:[:__<options>__]]::
 484     Setup bonding device <bondname> on top of <bondslaves>.
 485     <bondslaves> is a comma-separated list of physical (ethernet) interfaces.
 486     <options> is a comma-separated list on bonding options (modinfo bonding for details)
 487     in format compatible with initscripts. If <options> includes multi-valued arp_ip_target option,
 488     then its values should be separated by semicolon.
 489     Bond without parameters assumes bond=bond0:eth0,eth1:mode=balance-rr
 490
 491 **team=**__<teammaster>__:__<teamslaves>__::
 492     Setup team device <teammaster> on top of <teamslaves>.
 493     <teamslaves> is a comma-separated list of physical (ethernet) interfaces.
 494
 495 **bridge=**__<bridgename>__:__<ethnames>__::
 496     Setup bridge <bridgename> with <ethnames>. <ethnames> is a comma-separated
 497     list of physical (ethernet) interfaces. Bridge without parameters assumes bridge=br0:eth0
 498
 499 NFS
 500 ~~~
 501 **root=**\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__]::
 502     mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given, use
 503     dhcp next_server. if server-ip is an IPv6 address it has to be put in
 504     brackets, e.g. [2001:DB8::1]. NFS options can be appended with the prefix
 505     ":" or "," and are seperated by ",".
 506
 507 **root=**nfs:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**nfs4:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**__{dhcp|dhcp6}__::
 508     root=dhcp alone directs initrd to look at the DHCP root-path where NFS
 509     options can be specified.
 510 +
 511 [listing]
 512 .Example
 513 --
 514     root-path=<server-ip>:<root-dir>[,<nfs-options>]
 515     root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
 516     root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
 517 --
 518
 519 **root=**_/dev/nfs_ nfsroot=\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__]::
 520     _Deprecated!_ kernel Documentation_/filesystems/nfsroot.txt_ defines this
 521     method. This is supported by dracut, but not recommended.
 522
 523 **rd.nfs.domain=**__<NFSv4 domain name>__::
 524     Set the NFSv4 domain name. Will overwrite the settings in _/etc/idmap.conf_.
 525
 526 CIFS
 527 ~~~
 528 **root=**cifs://[__<username>__[:__<password>__]@]__<server-ip>__:__<root-dir>__::
 529     mount cifs share from <server-ip>:/<root-dir>, if no server-ip is given, use
 530     dhcp next_server. if server-ip is an IPv6 address it has to be put in
 531     brackets, e.g. [2001:DB8::1]. If a username or password are not specified
 532 as part of the root, then they must be passed on the command line through
 533 cifsuser/cifspass.
 534 +
 535 WARNING: Passwords specified on the kernel command line are visible for all users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the network, when using DHCP with DHCP root-path.
 536
 537 **cifsuser**=__<username>__::
 538     Set the cifs username, if not specified as part of the root.
 539
 540 **cifspass**=__<password>__::
 541     Set the cifs password, if not specified as part of the root.
 542 +
 543 WARNING: Passwords specified on the kernel command line are visible for all users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the network, when using DHCP with DHCP root-path.
 544
 545 iSCSI
 546 ~~~~~
 547 **root=**iscsi:[__<username>__:__<password>__[:__<reverse>__:__<password>__]@][__<servername>__]:[__<protocol>__]:[__<port>__][:[__<iscsi_iface_name>__]:[__<netdev_name>__]]:[__<LUN>__]:__<targetname>__::
 548     protocol defaults to "6", LUN defaults to "0". If the "servername" field is
 549     provided by BOOTP or DHCP, then that field is used in conjunction with other
 550     associated fields to contact the boot server in the Boot stage. However, if
 551     the "servername" field is not provided, then the "targetname" field is then
 552     used in the Discovery Service stage in conjunction with other associated
 553     fields. See
 554     link:$$http://tools.ietf.org/html/rfc4173#section-5$$[rfc4173].
 555 +
 556 WARNING: Passwords specified on the kernel command line are visible for all users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the network, when using DHCP with DHCP root-path.
 557 +
 558 [listing]
 559 .Example
 560 --
 561 root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
 562 --
 563 +
 564 If servername is an IPv6 address, it has to be put in brackets:
 565 +
 566 [listing]
 567 .Example
 568 --
 569 root=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
 570 --
 571
 572 **root=**__???__ **netroot=**iscsi:[__<username>__:__<password>__[:__<reverse>__:__<password>__]@][__<servername>__]:[__<protocol>__]:[__<port>__][:[__<iscsi_iface_name>__]:[__<netdev_name>__]]:[__<LUN>__]:__<targetname>__ ...::
 573     multiple netroot options allow setting up multiple iscsi disks:
 574 +
 575 [listing]
 576 .Example
 577 --
 578 root=UUID=12424547
 579 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
 580 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target1
 581 --
 582 +
 583 If servername is an IPv6 address, it has to be put in brackets:
 584 +
 585 [listing]
 586 .Example
 587 --
 588 netroot=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
 589 --
 590 +
 591 WARNING: Passwords specified on the kernel command line are visible for all users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the network, when using DHCP with DHCP root-path. You may want to use rd.iscsi.firmware.
 592
 593 **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>__::
 594     manually specify all iscsistart parameter (see **+iscsistart --help+**)
 595 +
 596 WARNING: Passwords specified on the kernel command line are visible for all users via the file _/proc/cmdline_ and via dmesg or can be sniffed on the network, when using DHCP with DHCP root-path. You may want to use rd.iscsi.firmware.
 597
 598 **root=**_???_ **netroot=**iscsi **rd.iscsi.firmware=1**::
 599  will read the iscsi parameter from the BIOS firmware
 600
 601 **rd.iscsi.param=**__<param>__::
 602     <param> will be passed as "--param <param>" to iscsistart.
 603     This parameter can be specified multiple times.
 604 +
 605 [listing]
 606 .Example
 607 --
 608 "netroot=iscsi rd.iscsi.firmware=1 rd.iscsi.param=node.session.timeo.replacement_timeout=30"
 609 --
 610 +
 611 will result in
 612 +
 613 [listing]
 614 --
 615 iscsistart -b --param node.session.timeo.replacement_timeout=30
 616 --
 617
 618 FCoE
 619 ~~~~
 620 **fcoe=**__<edd|interface|MAC>__:__{dcb|nodcb}__::
 621     Try to connect to a FCoE SAN through the NIC specified by _<interface>_ or
 622     _<MAC>_ or EDD settings. For the second argument, currently only nodcb is
 623     supported. This parameter can be specified multiple times.
 624 +
 625 NOTE: letters in the MAC-address must be lowercase!
 626
 627 NBD
 628 ~~~
 629 **root=**??? **netroot=**nbd:__<server>__:__<port>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
 630     mount nbd share from <server>
 631
 632 **root=dhcp** with **dhcp** **root-path=**nbd:__<server>__:__<port>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
 633     root=dhcp alone directs initrd to look at the DHCP root-path where NBD
 634     options can be specified. This syntax is only usable in cases where you are
 635     directly mounting the volume as the rootfs.
 636
 637 DASD
 638 ~~~~
 639 **rd.dasd=**....::
 640     same syntax as the kernel module parameter (s390 only)
 641
 642 ZFCP
 643 ~~~~
 644 **rd.zfcp=**__<zfcp adaptor device bus ID>__,__<WWPN>__,__<FCPLUN>__::
 645     rd.zfcp can be specified multiple times on the kernel command line.
 646 +
 647 [listing]
 648 .Example
 649 --
 650 rd.zfcp=0.0.4000,0x5005076300C213e9,0x5022000000000000
 651 --
 652
 653 **rd.zfcp.conf=0**::
 654     ignore zfcp.conf included in the initramfs
 655
 656 ZNET
 657 ~~~~
 658 **rd.znet=**__<nettype>__,__<subchannels>__,__<options>__::
 659     rd.znet can be specified multiple times on the kernel command line.
 660 +
 661 [listing]
 662 .Example
 663 --
 664 rd.znet=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,portname=foo
 665 rd.znet=ctc,0.0.0600,0.0.0601,protocol=bar
 666 --
 667
 668 Plymouth Boot Splash
 669 ~~~~~~~~~~~~~~~~~~~~
 670 **plymouth.enable=0**::
 671     disable the plymouth bootsplash completly.
 672
 673 **rd.plymouth=0**::
 674     disable the plymouth bootsplash only for the initramfs.
 675
 676 Kernel keys
 677 ~~~~~~~~~~~
 678 **masterkey=**__<kernel master key path name>__::
 679     Set the path name of the kernel master key.
 680 +
 681 [listing]
 682 .Example
 683 --
 684 masterkey=/etc/keys/kmk-trusted.blob
 685 --
 686
 687 **masterkeytype=**__<kernel master key type>__::
 688     Set the type of the kernel master key.
 689 +
 690 [listing]
 691 .Example
 692 --
 693 masterkeytype=trusted
 694 --
 695
 696 **evmkey=**__<EVM key path name>__::
 697     Set the path name of the EVM key.
 698 +
 699 [listing]
 700 .Example
 701 --
 702 evmkey=/etc/keys/evm-trusted.blob
 703 --
 704
 705 **ecryptfskey=**__<eCryptfs key path name>__::
 706     Set the path name of the eCryptfs key.
 707 +
 708 [listing]
 709 .Example
 710 --
 711 ecryptfskey=/etc/keys/ecryptfs-trusted.blob
 712 --
 713
 714 Deprecated, renamed Options
 715 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 716 Here is a list of options, which were used in dracut prior to version 008, and their new replacement.
 717
 718 rdbreak:: rd.break
 719
 720 rd_CCW:: rd.ccw
 721
 722 rd_DASD_MOD:: rd.dasd
 723
 724 rd_DASD:: rd.dasd
 725
 726 rdinitdebug rdnetdebug:: rd.debug
 727
 728 rd_NO_DM:: rd.dm=0
 729
 730 rd_DM_UUID:: rd.dm.uuid
 731
 732 rdblacklist:: rd.driver.blacklist
 733
 734 rdinsmodpost:: rd.driver.post
 735
 736 rdloaddriver:: rd.driver.pre
 737
 738 rd_NO_FSTAB:: rd.fstab=0
 739
 740 rdinfo:: rd.info
 741
 742 check:: rd.live.check
 743
 744 rdlivedebug:: rd.live.debug
 745
 746 live_dir:: rd.live.dir
 747
 748 liveimg:: rd.live.image
 749
 750 overlay:: rd.live.overlay
 751
 752 readonly_overlay:: rd.live.overlay.readonly
 753
 754 reset_overlay:: rd.live.overlay.reset
 755
 756 live_ram:: rd.live.ram
 757
 758 rd_NO_CRYPTTAB:: rd.luks.crypttab=0
 759
 760 rd_LUKS_KEYDEV_UUID:: rd.luks.keydev.uuid
 761
 762 rd_LUKS_KEYPATH:: rd.luks.keypath
 763
 764 rd_NO_LUKS:: rd.luks=0
 765
 766 rd_LUKS_UUID:: rd.luks.uuid
 767
 768 rd_NO_LVMCONF:: rd.lvm.conf
 769
 770 rd_LVM_LV:: rd.lvm.lv
 771
 772 rd_NO_LVM:: rd.lvm=0
 773
 774 rd_LVM_SNAPSHOT:: rd.lvm.snapshot
 775
 776 rd_LVM_SNAPSIZE:: rd.lvm.snapsize
 777
 778 rd_LVM_VG:: rd.lvm.vg
 779
 780 rd_NO_MDADMCONF:: rd.md.conf=0
 781
 782 rd_NO_MDIMSM:: rd.md.imsm=0
 783
 784 rd_NO_MD:: rd.md=0
 785
 786 rd_MD_UUID:: rd.md.uuid
 787
 788 rd_NFS_DOMAIN:: rd.nfs.domain
 789
 790 iscsi_initiator:: rd.iscsi.initiator
 791
 792 iscsi_target_name:: rd.iscsi.target.name
 793
 794 iscsi_target_ip:: rd.iscsi.target.ip
 795
 796 iscsi_target_port:: rd.iscsi.target.port
 797
 798 iscsi_target_group:: rd.iscsi.target.group
 799
 800 iscsi_username:: rd.iscsi.username
 801
 802 iscsi_password:: rd.iscsi.password
 803
 804 iscsi_in_username:: rd.iscsi.in.username
 805
 806 iscsi_in_password:: rd.iscsi.in.password
 807
 808 iscsi_firmware:: rd.iscsi.firmware=0
 809
 810 rd_NO_PLYMOUTH:: rd.plymouth=0
 811
 812 rd_retry:: rd.retry
 813
 814 rdshell:: rd.shell
 815
 816 rd_NO_SPLASH:: rd.splash
 817
 818 rdudevdebug:: rd.udev.debug
 819
 820 rdudevinfo:: rd.udev.info
 821
 822 rd_NO_ZFCPCONF:: rd.zfcp.conf=0
 823
 824 rd_ZFCP:: rd.zfcp
 825
 826 rd_ZNET:: rd.znet
 827
 828 KEYMAP:: vconsole.keymap
 829
 830 KEYTABLE:: vconsole.keymap
 831
 832 SYSFONT:: vconsole.font
 833
 834 CONTRANS:: vconsole.font.map
 835
 836 UNIMAP:: vconsole.font.unimap
 837
 838 UNICODE:: vconsole.unicode
 839
 840 EXT_KEYMAP:: vconsole.keymap.ext
 841
 842 Configuration in the Initramfs
 843 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 844 _/etc/conf.d/_::
 845     Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
 846     set initial values. Command line options will override these values
 847     set in the configuration files.
 848
 849 _/etc/cmdline_::
 850     Can contain additional command line options. Deprecated, better use /etc/cmdline.d/*.conf.
 851
 852 _/etc/cmdline.d/*.conf_::
 853     Can contain additional command line options.
 854
 855 AUTHOR
 856 ------
 857 Harald Hoyer
 858
 859 SEE ALSO
 860 --------
 861 *dracut*(8) *dracut.conf*(5)