dracut/dracut.cmdline.7.asc

DRACUT.CMDLINE(7)
=================
:doctype: manpage
:man source:   dracut
:man manual:   dracut

NAME
----
dracut.cmdline - dracut kernel command line options

DESCRIPTION
-----------
The root device used by the kernel is specified in the boot configuration
file on the kernel command line, as always.

The traditional _root=/dev/sda1_ style device specification is allowed, but not
encouraged. The root device should better be identified by LABEL or UUID. If a
label is used, as in _root=LABEL=<label_of_root>_ the initramfs will search all
available devices for a filesystem with the appropriate label, and mount that
device as the root filesystem. _root=UUID=<uuidnumber>_ will mount the partition
with that UUID as the root filesystem.

In the following all kernel command line parameters, which are processed by
dracut, are described.

"rd.*" parameters mentioned without "=" are boolean parameters. They can be
turned on/off by setting them to {0|1}. If the assignment with "=" is missing
"=1" is implied. For example _rd.info_ can be turned off with _rd.info=0_ or
turned on with _rd.info=1_ or _rd.info_. The last value in the kernel command
line is the value, which is honored.

Standard
~~~~~~~~
**init=**_<path to real init>_::
    specify the path to the init programm to be started after the initramfs has
    finished

**root=**_<path to blockdevice>_::
    specify the block device to use as the root filesystem.
+
E.g.:
+
----
root=/dev/sda1
root=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
root=/dev/disk/by-label/Root
root=LABEL=Root
root=/dev/disk/by-uuid/3f5ad593-4546-4a94-a374-bcfb68aa11f7
root=UUID=3f5ad593-4546-4a94-a374-bcfb68aa11f7
----

**rootfstype=**_<filesystem type>_:: "auto" if not specified, e.g.:
+
----
rootfstype=ext3
----

**rootflags=**_<mount options>_::
    specify additional mount options for the root filesystem. If not set,
    _/etc/fstab_ of the real root will be parsed for special mount options and
    mounted accordingly.

**rd.fstab=0**::
    do not honor special mount options for the root filesystem found in
    _/etc/fstab_ of the real root.

Misc
~~~~
**rd.driver.blacklist=**_<drivername>[,<drivername>,...]_::
    do not load kernel module <drivername>. This parameter can be specified
    multiple times.

**rd.driver.pre=**_<drivername>[,<drivername>,...]_::
    force loading kernel module <drivername>. This parameter can be specified
    multiple times.

**rd.driver.post=**_<drivername>[,<drivername>,...]_::
    force loading kernel module <drivername> after all automatic loading modules
    have been loaded. This parameter can be specified multiple times.

[[dracutkerneldebug]]
Debug
~~~~~
**rd.info**::
    print informational output though "quiet" is set

**rd.shell**::
    allow dropping to a shell, if root mounting fails

**rd.debug**::
    set -x for the dracut shell and logs to dmesg, console and
    _/run/initramfs/init.log_

**rd.break**::
    drop to a shell at the end

**rd.break=**_{cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount|pre-pivot}_::
    drop to a shell on defined breakpoint

**rd.udev.info**::
    set udev to loglevel info

**rd.udev.debug**::
    set udev to loglevel debug

I18N
~~~~
**vconsole.keymap=**_<keymap base file name>_::
    keyboard translation table loaded by loadkeys; taken from keymaps directory;
    will be written as KEYMAP to _/etc/vconsole.conf_ in the initramfs, e.g.:
+
----
vconsole.keymap=de-latin1-nodeadkeys
----

**vconsole.keymap.ext=**_<list of keymap base file names>_::
    list of extra keymaps to bo loaded (sep. by space); will be written as
    EXT_KEYMAP to _/etc/vconsole.conf_ in the initramfs

**vconsole.unicode**[=_{0|1}_]::
    boolean, indicating UTF-8 mode; will be written as UNICODE to
    _/etc/vconsole.conf_ in the initramfs

**vconsole.font=**_<font base file name>_::
    console font; taken from consolefonts directory; will be written as FONT to
    _/etc/vconsole.conf_ in the initramfs; e.g.:
+
----
vconsole.font=LatArCyrHeb-16
----

**vconsole.font.map=**_<console map base file name>_::
    see description of '-m' parameter in setfont manual; taken from consoletrans
    directory; will be written as FONT_MAP to _/etc/vconsole.conf_ in the
    initramfs

**vconsole.font.unimap=**_<unicode table base file name>_::
    see description of '-u' parameter in setfont manual; taken from unimaps
    directory; will be written as FONT_UNIMAP to _/etc/vconsole.conf_ in the
    initramfs

**locale.LANG=**_<locale>_::
    taken from the environment; if no UNICODE is defined we set its value in
    basis of LANG value (whether it ends with ".utf8" (or similar) or not); will
    be written as LANG to _/etc/locale.conf_ in the initramfs; e.g.:
+
----
locale.LANG=pl_PL.utf8
----

**locale.LC_ALL=**_<locale>_::
    taken from the environment; will be written as LC_ALL to _/etc/locale.conf_
    in the initramfs

LVM
~~~
**rd.lvm=0**::
    disable LVM detection

**rd.lvm.vg=**_<volume group name>_::
    only activate the volume groups with the given name. rd.lvm.vg can be
    specified multiple times on the kernel command line.

**rd.lvm.lv=**_<logical volume name>_::
    only activate the logical volumes with the given name. rd.lvm.lv can be
    specified multiple times on the kernel command line.

**rd.lvm.conf=0**::
    remove any _/etc/lvm/lvm.conf_, which may exist in the initramfs

crypto LUKS
~~~~~~~~~~~
**rd.luks=0**::
    disable crypto LUKS detection

**rd.luks.uuid=**_<luks uuid>_::
    only activate the LUKS partitions with the given UUID. Any "luks-" of the
    LUKS UUID is removed before comparing to _<luks uuid>_.
    The comparisons also matches, if _<luks uuid>_ is only the beginning of the
    LUKS UUID, so you don't have to specify the full UUID.
    This parameter can be specified multiple times.

**rd.luks.crypttab=0**::
    do not check, if LUKS partition is in _/etc/crypttab_

crypto LUKS - key on removable device support
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
**rd.luks.key=**_<keypath>:<keydev>:<luksdev>_::
    _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.
+
_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.
+
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:
+
----
rd.luks.key=/foo/bar.key
----
+
As you see, you can skip colons in such a case.

MD RAID
~~~~~~~
**rd.md=0**::
    disable MD RAID detection

**rd.md.imsm=0**::
    disable MD RAID for imsm/isw raids, use DM RAID instead

**rd.md.ddf=0**::
    disable MD RAID for SNIA ddf raids, use DM RAID instead

**rd.md.conf=0**::
    ignore mdadm.conf included in initramfs

**rd.md.waitclean=1**::
    wait for any resync, recovery, or reshape activity to finish before continuing

**rd.md.uuid=**_<md raid uuid>_::
    only activate the raid sets with the given UUID. This parameter can be
    specified multiple times.

DM RAID
~~~~~~~
**rd.dm=0**::
    disable DM RAID detection

**rd.dm.uuid=**_<dm raid uuid>_::
   only activate the raid sets with the given UUID. This parameter can be
   specified multiple times.

FIPS
~~~~
**rd.fips**::
    enable FIPS

**boot=**_<boot device>_::
    specify the device, where /boot is located. e.g.
+
----
boot=/dev/sda1
boot=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
boot=UUID=<uuid>
boot=LABEL=<label>
----

**rd.fips.skipkernel**::
    skip checksum check of the kernel image. Useful, if the kernel image is not
    in a separate boot partition.

Network
~~~~~~~
**ip=**_{dhcp|on|any|dhcp6|auto6|ibft}_::
    dhcp|on|any::: get ip from dhcp server from all interfaces. If root=dhcp, loop
    sequentially through all interfaces (eth0, eth1, ...) and use the first with
    a valid DHCP root-path.

    auto6::: IPv6 autoconfiguration

    dhcp6::: IPv6 DHCP

    ibft::: iBFT autoconfiguration

**ip=**_<interface>_:_{dhcp|on|any|dhcp6|auto6}_::
    This parameter can be specified multiple times.
+
dhcp|on|any|dhcp6::: get ip from dhcp server on a specific interface
auto6::: do IPv6 autoconfiguration

**ip=**_<client-IP>_:_<server-IP>_:_<gateway-IP>_:_<netmask>_:_<client_hostname>_:_<interface>_:_{none|off}_::
    explicit network configuration. If you want do define a IPv6 address, put it
    in brackets (e.g. [2001:DB8::1]). This parameter can be specified multiple
    times.

**ifname=**_<interface>_:_<MAC>_::
    Assign network device name <interface> (ie eth0) to the NIC with MAC <MAC>.
    Note: If you use this option you _must_ specify an ifname= argument for all
    interfaces used in ip= or fcoe= arguments. This parameter can be specified
    multiple times.

**bootdev=**_<interface>_::
    specify network interface to use routing and netroot information from.
    Required if multiple ip= lines are used.

**nameserver=**__<IP>__ [**nameserver=**__<IP>__ ...]::
    specify nameserver(s) to use

**biosdevname=0**::
    boolean, turn off biosdevname network interface renaming

**rd.neednet=1**::
    boolean, bring up network even without netroot set

NFS
~~~
**root=**[_<server-ip>_:]_<root-dir>_[:_<nfs-options>_]::
    mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given, use
    dhcp next_server. if server-ip is an IPv6 address it has to be put in
    brackets, e.g. [2001:DB8::1]. NFS options can be appended with the prefix
    ":" or "," and are seperated by ",".

**root=**nfs:[_<server-ip>_:]_<root-dir>_[:_<nfs-options>_], **root=**nfs4:[_<server-ip>_:]_<root-dir>_[:_<nfs-options>_], **root=**_{dhcp|dhcp6}_::
    root=dhcp alone directs initrd to look at the DHCP root-path where NFS
    options can be specified.
+
----
    root-path=<server-ip>:<root-dir>[,<nfs-options>]
    root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
    root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
----

**root=**_/dev/nfs_ nfsroot=[_<server-ip>_:]_<root-dir>_[:_<nfs-options>_]::
    _Deprecated!_ kernel Documentation_/filesystems/nfsroot.txt_ defines this
    method. This is supported by dracut, but not recommended.

**rd.nfs.domain=**_<NFSv4 domain name>_::
    Set the NFSv4 domain name. Will overwrite the settings in _/etc/idmap.conf_.

iSCSI
~~~~~
**root=**iscsi:[_<username>_:_<password>_[:_<reverse>_:_<password>_]@][_<servername>_]:[_<protocol>_]:[_<port>_][:[_<iscsi_iface_name>_]:[_<netdev_name>_]]:[_<LUN>_]:_<targetname>_::
    protocol defaults to "6", LUN defaults to "0". If the "servername" field is
    provided by BOOTP or DHCP, then that field is used in conjunction with other
    associated fields to contact the boot server in the Boot stage. However, if
    the "servername" field is not provided, then the "targetname" field is then
    used in the Discovery Service stage in conjunction with other associated
    fields. See
    link:$$http://tools.ietf.org/html/rfc4173#section-5$$[rfc4173].
    e.g.:
+
----
root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
----
+
If servername is an IPv6 address, it has to be put in brackets. e.g.:
+
----
root=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
----

**root=**_???_ **netroot=**iscsi:[_<username>_:_<password>_[:_<reverse>_:_<password>_]@][_<servername>_]:[_<protocol>_]:[_<port>_][:[_<iscsi_iface_name>_]:[_<netdev_name>_]]:[_<LUN>_]:_<targetname>_ ...::
    multiple netroot options allow setting up multiple iscsi disks. e.g.:
+
----
root=UUID=12424547
netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target1
----
+
If servername is an IPv6 address, it has to be put in brackets. e.g.:
+
----
netroot=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
----

**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>_::
    manually specify all iscsistart parameter (see **+iscsistart --help+**)

**root=**_???_ **netroot=**iscsi **rd.iscsi.firmware=1**::
 will read the iscsi parameter from the BIOS firmware

**rd.iscsi_param=**_<param>_::
    <param> will be passed as "--param <param>" to iscsistart.
    This parameter can be specified multiple times.
    e.g.:
+
----
"netroot=iscsi iscsi_firmware rd.iscsi_param=node.session.timeo.replacement_timeout=30"
----
+
will result in
+
----
iscsistart -b --param node.session.timeo.replacement_timeout=30
----

FCoE
~~~~
**fcoe=**_<edd|interface|MAC>_:_{dcb|nodcb}_::
    Try to connect to a FCoE SAN through the NIC specified by _<interface>_ or
    _<MAC>_ or EDD settings. For the second argument, currently only nodcb is
    supported. This parameter can be specified multiple times. Note: letters in
    the MAC-address must be lowercase!

NBD
~~~
**root=**??? **netroot=**nbd:_<server>_:_<port>_[:_<fstype>_[:_<mountopts>_[:_<nbdopts>_]]]::
    mount nbd share from <server>

**root=dhcp** with **dhcp** **root-path=**nbd:_<server>_:_<port>_[:_<fstype>_[:_<mountopts>_[:_<nbdopts>_]]]::
    root=dhcp alone directs initrd to look at the DHCP root-path where NBD
    options can be specified. This syntax is only usable in cases where you are
    directly mounting the volume as the rootfs.

DASD
~~~~
**rd.dasd_mod.dasd=**....::
    same syntax as the kernel module parameter (s390 only)

**rd.dasd=**_<dasd_adaptor device bus ID>_[,readonly=_X_][,use_diag=_X_][,erplog=_X_]::
    activate DASD device with the given adaptor device bus ID and setting the
    sysfs attributes to the specified values. This parameter can be specified
    multiple times.

ZFCP
~~~~
**rd.zfcp=**_<zfcp adaptor device bus ID>_,_<WWPN>_,_<FCPLUN>_::
    rd.zfcp can be specified multiple times on the kernel command line. e.g.: 
+
----
rd.zfcp=0.0.4000,0x5005076300C213e9,0x5022000000000000
----

**rd.zfcp.conf=0**::
    ignore zfcp.conf included in the initramfs

ZNET
~~~~
**rd.znet=**_<nettype>_,_<subchannels>_,_<options>_::
    rd.znet can be specified multiple times on the kernel command line. e.g.: 
+
----
rd.znet=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,portname=foo
rd.znet=ctc,0.0.0600,0.0.0601,0.0.0602,protocol=bar
----

Plymouth Boot Splash
~~~~~~~~~~~~~~~~~~~~
**plymouth.enable=0**::
    disable the plymouth bootsplash completly.

**rd.plymouth=0**::
    disable the plymouth bootsplash only for the initramfs.

Kernel keys
~~~~~~~~~~~
**masterkey=**_<kernel master key path name>_::
    Set the path name of the kernel master key. e.g.: 
+
----
masterkey=/etc/keys/kmk-trusted.blob
----

**masterkeytype=**_<kernel master key type>_::
    Set the type of the kernel master key. e.g.: 
+
----
masterkeytype=trusted
----

**evmkey=**_<EVM key path name>_::
    Set the path name of the EVM key. e.g.: 
+
----
evmkey=/etc/keys/evm-trusted.blob
----

**ecryptfskey=**_<eCryptfs key path name>_::
    Set the path name of the eCryptfs key. e.g.: 
+
----
ecryptfskey=/etc/keys/ecryptfs-trusted.blob
----

Deprecated, renamed Options
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Here is a list of options, which were used in dracut prior to version 008, and their new replacement.

rdbreak:: rd.break

rd_CCW:: rd.ccw

rd_DASD_MOD:: rd.dasd_mod.dasd

rd_DASD:: rd.dasd

rdinitdebug rdnetdebug:: rd.debug

rd_NO_DM:: rd.dm=0

rd_DM_UUID:: rd.dm.uuid

rdblacklist:: rd.driver.blacklist

rdinsmodpost:: rd.driver.post

rdloaddriver:: rd.driver.pre

rd_NO_FSTAB:: rd.fstab=0

rdinfo:: rd.info

check:: rd.live.check

rdlivedebug:: rd.live.debug

live_dir:: rd.live.dir

liveimg:: rd.live.image

overlay:: rd.live.overlay

readonly_overlay:: rd.live.overlay.readonly

reset_overlay:: rd.live.overlay.reset

live_ram:: rd.live.ram

rd_NO_CRYPTTAB:: rd.luks.crypttab=0

rd_LUKS_KEYDEV_UUID:: rd.luks.keydev.uuid

rd_LUKS_KEYPATH:: rd.luks.keypath

rd_NO_LUKS:: rd.luks=0

rd_LUKS_UUID:: rd.luks.uuid

rd_NO_LVMCONF:: rd.lvm.conf

rd_LVM_LV:: rd.lvm.lv

rd_NO_LVM:: rd.lvm=0

rd_LVM_SNAPSHOT:: rd.lvm.snapshot

rd_LVM_SNAPSIZE:: rd.lvm.snapsize

rd_LVM_VG:: rd.lvm.vg

rd_NO_MDADMCONF:: rd.md.conf=0

rd_NO_MDIMSM:: rd.md.imsm=0

rd_NO_MD:: rd.md=0

rd_MD_UUID:: rd.md.uuid

rd_NFS_DOMAIN:: rd.nfs.domain

iscsi_initiator:: rd.iscsi.initiator

iscsi_target_name:: rd.iscsi.target.name

iscsi_target_ip:: rd.iscsi.target.ip

iscsi_target_port:: rd.iscsi.target.port

iscsi_target_group:: rd.iscsi.target.group

iscsi_username:: rd.iscsi.username

iscsi_password:: rd.iscsi.password

iscsi_in_username:: rd.iscsi.in.username

iscsi_in_password:: rd.iscsi.in.password

iscsi_firmware:: rd.iscsi.firmware=0

rd_NO_PLYMOUTH:: rd.plymouth=0

rd_retry:: rd.retry

rdshell:: rd.shell

rd_NO_SPLASH:: rd.splash

rdudevdebug:: rd.udev.debug

rdudevinfo:: rd.udev.info

rd_NO_ZFCPCONF:: rd.zfcp.conf=0

rd_ZFCP:: rd.zfcp

rd_ZNET:: rd.znet

KEYMAP:: vconsole.keymap

KEYTABLE:: vconsole.keymap

SYSFONT:: vconsole.font

CONTRANS:: vconsole.font.map

UNIMAP:: vconsole.font.unimap

UNICODE:: vconsole.unicode

EXT_KEYMAP:: vconsole.keymap.ext

Configuration in the Initramfs
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
_/etc/conf.d/_::
    Any files found in _/etc/conf.d/_ will be sourced in the initramfs to
    set initial values. Command line options will override these values
    set in the configuration files.

_/etc/cmdline_::
    Can contain additional command line options.

_/etc/cmdline.d/*.conf_::
    Can contain additional command line options.

AUTHOR
------
*Harald Hoyer*::
    Project Leader and Developer

SEE ALSO
--------
*dracut*(8) *dracut.conf*(5)