NAME
dracut - create initial ramdisk images for preloading modules
SYNOPSIS
dracut [OPTION]... <image> <kernel-version>
DESCRIPTION
dracut creates an initial image used by the kernel for preloading the
block device modules (such as IDE, SCSI or RAID) which are needed to
access the root filesystem.
Options
-f, --force
overwrite existing initramfs file.
-m, --modules LIST
specify a space-separated list of dracut modules to call when
building the initramfs. Modules are located in
/usr/share/dracut/modules.d.
-o, --omit LIST
omit a space-separated list of dracut modules.
-a, --add LIST
add a space-separated list of dracut modules.
-d, --drivers LIST
specify a space-separated list of kernel modules to exclusively
include# in the initramfs. --add-drivers LIST specify a space-
separated list of kernel modules to add to the initramfs.
--filesystems LIST
specify a space-separated list of kernel filesystem modules to
exclusively include in the generic initramfs.
-k, --kmoddir {DIR}
specify the directory, where to look for kernel modules
--fwdir {DIR}
specify additional directory, where to look for firmwares
--kernel-only
only install kernel drivers and firmware files
--no-kernel
do not install kernel drivers and firmware files
--mdadmconf
include local /etc/mdadm.conf
--nomdadmconf
do not include local /etc/mdadm.conf
--strip
strip binaries in the initramfs (default)
--nostrip
do not strip binaries in the initramfs
-h, --help
display help text and exit.
--debug
output debug information of the build process
-v, --verbose
verbose output during the build process
-c, --conf FILE
specify configuration file to use. Default: /etc/dracut.conf
--confdir DIR
specify configuration directory to use. Default:
/etc/dracut.conf.d
-l, --local
local mode. Use modules from the current working directory
instead of the system-wide installed in
/usr/share/dracut/modules.d. Useful when running dracut from a
git checkout.
-H, --hostonly
Host-Only mode: Install only what is needed for booting the
local host instead of a generic host.
-i, --include SOURCE TARGET
include the files in the SOURCE directory into the target
directory in the final initramfs.
-I, --install LIST
install the space separated list of files into the initramfs.
KERNEL COMMAND LINE
The root filesystem used by the kernel is specified in the boot
configuration file, as always. The traditional root=/dev/hda1 style
device specification is allowed. If a label is used, as in
root=LABEL=rootPart the initrd will search all available devices for an
ext2 or ext3 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.
Standard
init=<path to real init>
root=<path to blockdevice>
specify blockdevice to use as root filesystem.
e.g.
root=/dev/sda1
root=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
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_NO_FSTAB
do not honor special mount options for the root filesystem found
in /etc/fstab of the real root.
Misc
rdblacklist=<drivername>
do not load kernel module <drivername>
rdloaddriver=<drivername>
force loading kernel module <drivername>
Debug
rdinfo print informational output though "quiet" is set
rdshell
allow dropping to a shell, if root mounting fails
rdinitdebug
set -x for the dracut shell and logs to dmesg, console and
/init.log
rdbreak
drop to a shell at the end
rdbreak={cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount |pre-
pivot}
drop to a shell on defined breakpoint
rdudevinfo
set udev to loglevel info
rdudevdebug
set udev to loglevel debug
rdnetdebug
debug network scripts in dracut. Output is written to /tmp/
I18N
e.g.
LANG=en_US.UTF-8
SYSFONT=latarcyrheb-sun16
KEYTABLE=de-latin1-nodeadkeys
KEYBOARDTYPE=sun|pc
will be written to /etc/sysconfig/keyboard in the initramfs
KEYTABLE=<keytable filename>
will be written to /etc/sysconfig/keyboard in the initramfs
SYSFONT=Console font
will be written to /etc/sysconfig/i18n in the initramfs
SYSFONTACM=Unicode font map
will be written to /etc/sysconfig/i18n in the initramfs
UNIMAP=Unicode font map
will be written to /etc/sysconfig/i18n in the initramfs
LANG=<locale>
will be written to /etc/sysconfig/i18n in the initramfs
LVM
rd_NO_LVM
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 volume groups with the given name rd_LVM_LV
can be specified multiple times on the kernel command line.
rd_NO_LVMCONF
remove any /etc/lvm/lvm.conf, which may exist in the initramfs
crypto LUKS
rd_NO_LUKS
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. rd_NO_CRYPTTAB do not check if LUKS partition is in
/etc/crypttab
MD
rd_NO_MD
disable MD RAID detection
rd_NO_MDIMSM
no MD RAID for imsm/isw raids, use dmraid instead
rd_NO_MDADMCONF
ignore mdadm.conf included in initramfs
rd_MD_UUID=<md uuid>
only activate the raid sets with the given UUID
DMRAID
rd_NO_DM
disable DM RAID detection
rd_DM_UUID=<dmraid uuid>
only activate the raid sets with the given UUID
Network
ip={dhcp|on|any|dhcp6|auto6}
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: do IPv6 autoconfiguration
ip=<interface>:{dhcp|on|any|dhcp6|auto6}
dhcp|on|any|dhcp6: get ip from dhcp server on a specific
interface
auto6: do IPv6 autoconfiguration
ip=<client-IP>:[<server-id>]:<gateway-IP>:<netmask>:<clienthostname>
:<interface>:{none|off}
explicit network configuration. If you want do define a IPv6
address, put it in brackets (e.g. [2001:DB8::1]).
ifname=<interface>:<MAC>
Assign network device name <interface> (ie eth0) to the NIC with
MAC <MAC>. Note letters in the MAC-address must be lowercase!
Note that if you use this option you must specify an ifname=
argument for all interfaces used in ip= or fcoe= arguments
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
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. 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>]:[<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 (Section 7).
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.
http://tools.ietf.org/html/rfc4173
root=iscsi:[username:password[:reverse:password]@][<servername>]
:[<protocol>]:[<port>]:[<LUN>]:<targetname>
e.g. root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
root=??? netroot=iscsi:[username:password[:reverse:password]@]
[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname> ...
multiple netroot options allow setting up multiple iscsi disks
Not yet implemented!
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
root=??? iscsi_initiator=<initiator> iscsi_target_name=<target name>
iscsi_target_ip=<target ip> iscsi_target_port=<target port>
iscsi_target_group=<target group> iscsi_username=<username>
iscsi_password=<password> iscsi_in_username=<in username>
iscsi_in_password=<in password>
manually specify all iscsistart parameter (see
iscsistart --help)
root=??? iscsi_firmware
will read the iscsi parameter from the BIOS firmware
FCoE
netroot=fcoe:<interface|MAC>:<dcb|nodcb>
Try to connect to a FCoE SAN through the NIC specified by
<interface> or <MAC>, for the second argument, currently only
nodcb is supported. Note letters in the MAC-address must be
lowercase!
NBD
root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
mount nbd share from <server>
root=dhcp
with dhcp root-path=nbd:<server>:<port>[:<fstype>][:<mountopts>]
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=....
same syntax as the kernel module parameter (s390 only)
rd_DASD=<dasd adaptor device bus ID>[,readonly=X][,use_diag=X]
[,erplog=X][,failfast=X]
activate DASD device with the given adaptor device bus ID and
setting the sysfs attributes to the specified values
ZFCP
rd_ZFCP=<zfcp adaptor device bus ID>,<WWPN>,<FCPLUN>
rd_ZFCP can be specified multiple times on the kernel command
line.
example: rd_ZFCP=0.0.4000,0x5005076300C213e9,0x5022000000000000
rd_NO_ZFCPCONF
ignore zfcp.conf included in the initramfs
CCW
rd_CCW=<nettype>,<subchannels>,<options>
rd_CCW can be specified multiple times on the kernel command
line. Examples:
rd_CCW=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,portname=foo
rd_CCW=ctc,0.0.0600,0.0.0601,0.0.0602,protocol=bar
Plymouth Boot Splash
rd_NO_PLYMOUTH
do not start plymouth. This will not work with encrypted
partitions.
FILES
/var/log/dracut.log
/tmp/dracut.log
see dracut.conf(5)
/etc/dracut.conf
Configuration in the Initramfs
/conf/conf.d/
Any files found in /conf/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.
AUTHORS
Harald Hoyer <harald@redhat.com>
Victor Lowther <victor.lowther@gmail.com>
Warren Togami <wtogami@redhat.com>
Jeremy Katz <katzj@redhat.com>
Philippe Seewer <philippe.seewer@bfh.ch>
David Dillow <dave@thedillows.org>
AVAILABILITY
The dracut command is part of the dracut package and is available from
http://sourceforge.net/apps/trac/dracut/wiki
SEE ALSO
dracut.conf(5)