DRACUT(8) DRACUT(8)

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/dra- cut/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. The kernel modules have to be speci- fied without the ".ko" suffix.

--add-drivers LIST specify a space-separated list of kernel modules to add to the initramfs. The kernel modules have to be specified without the ".ko" suffix.

--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/dra- cut.conf.d

-l, --local local mode. Use modules from the current working directory instead of the system-wide installed in /usr/share/dracut/mod- ules.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 direc- tory 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 config- uration 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> This parameter can be specified multiple times.

rdloaddriver=<drivername> force loading kernel module <drivername> This parameter can be specified multiple times.

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

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 logical volumes 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 dont have to specify the full UUID. This parameter can be specified multiple times.

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. This parameter can be specified multiple times.

DMRAID rd_NO_DM disable DM RAID detection

rd_DM_UUID=<dmraid uuid> only activate the raid sets with the given UUID. This parameter can be specified multiple times.

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 inter- face auto6: do IPv6 autoconfiguration This parameter can be specified multiple times.

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]). This parame- ter can be specified multiple times.

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 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

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>]:[<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). How- ever, if the "servername" field is not provided, then the "tar- getname" 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

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>]:[<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=??? 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 iscsis- tart --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 low- ercase!

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 This param- eter 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.

example: rd_ZFCP=0.0.4000,0x5005076300C213e9,0x5022000000000000

rd_NO_ZFCPCONF 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. Examples: rd_ZNET=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,port- name=foo rd_ZNET=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 parti- tions.

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 over- ride 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)

Linux June 2009 DRACUT(8)