1DRACUT(8) System Manager's Manual DRACUT(8)
2
6 dracut - create initial ramdisk images for preloading modules
7
9 dracut [OPTION]... <image> <kernel-version>
10
13 dracut creates an initial image used by the kernel for preloading the
14 block device modules (such as IDE, SCSI or RAID) which are needed to
15 access the root filesystem.
16 Options
19 -f, --force
20 overwrite existing initramfs file.
21 -m, --modules LIST
23 specify a space-separated list of dracut modules to call when
24 building the initramfs. Modules are located in /usr/share/dra‐
25 cut/modules.d.
26 -o, --omit LIST
28 omit a space-separated list of dracut modules.
29 -a, --add LIST
31 add a space-separated list of dracut modules.
32 -d, --drivers LIST
34 specify a space-separated list of kernel modules to exclusively
35 include in the initramfs. The kernel modules have to be speci‐
36 fied without the ".ko" suffix.
37 --add-drivers LIST
39 specify a space-separated list of kernel modules to add to the
40 initramfs. The kernel modules have to be specified without the
41 ".ko" suffix.
42 --omit-drivers LIST
44 specify a space-separated list of kernel modules to omit from
45 the initramfs. The kernel modules have to be specified without
46 the ".ko" suffix. Regular expressions are also allowed like
47 ".*/fs/ocfs/.*".
48 If [LIST] has multiple arguments, then you have to put these in
50 quotes.
51 example: # dracut --omit "module1 module2" ...
53 --filesystems LIST
55 specify a space-separated list of kernel filesystem modules to
56 exclusively include in the generic initramfs.
57 -k, --kmoddir {DIR}
59 specify the directory, where to look for kernel modules
60 --fwdir {DIR}
62 specify additional directory, where to look for firmwares
63 --kernel-only
65 only install kernel drivers and firmware files
66 --no-kernel
68 do not install kernel drivers and firmware files
69 --mdadmconf
71 include local /etc/mdadm.conf
72 --nomdadmconf
74 do not include local /etc/mdadm.conf
75 --strip
77 strip binaries in the initramfs (default)
78 --nostrip
80 do not strip binaries in the initramfs
81 -h, --help
83 display help text and exit.
84 --debug
86 output debug information of the build process
87 -v, --verbose
89 verbose output during the build process
90 -c, --conf FILE
92 specify configuration file to use. Default: /etc/dracut.conf
93 --confdir DIR
95 specify configuration directory to use. Default: /etc/dra‐
96 cut.conf.d
97 -l, --local
99 local mode. Use modules from the current working directory
100 instead of the system-wide installed in /usr/share/dracut/mod‐
101 ules.d. Useful when running dracut from a git checkout.
102 -H, --hostonly
104 Host-Only mode: Install only what is needed for booting the
105 local host instead of a generic host.
106 -i, --include SOURCE TARGET
108 include the files in the SOURCE directory into the target direc‐
109 tory in the final initramfs.
110 -I, --install LIST
112 install the space separated list of files into the initramfs.
113
116 The root filesystem used by the kernel is specified in the boot config‐
117 uration file, as always. The traditional root=/dev/hda1 style device
118 specification is allowed. If a label is used, as in root=LABEL=rootPart
119 the initrd will search all available devices for an ext2 or ext3
120 filesystem with the appropriate label, and mount that device as the
121 root filesystem. root=UUID=uuidnumber will mount the partition with
122 that UUID as the root filesystem.
123 Standard
126 init=<path to real init>
127 root=<path to blockdevice>
129 specify blockdevice to use as root filesystem.
130 e.g.
131 root=/dev/sda1
132 root=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
133 rootfstype=<filesystem type>
135 "auto" if not specified, e.g. rootfstype=ext3
136 rootflags=<mount options>
138 specify additional mount options for the root filesystem. If not
139 set, /etc/fstab of the real root will be parsed for special
140 mount options and mounted accordingly.
141 rootfallback=<path to blockdevice>
143 specify the block device to use as the root filesystem, if the
144 normal root cannot be found. This can only be a simple block
145 device with a simple file system, for which the filesystem
146 driver is either compiled in, or added manually to the
147 initramfs. This parameter can be specified multiple times.
148 rd_NO_FSTAB
150 do not honor special mount options for the root filesystem found
151 in /etc/fstab of the real root.
152 Misc
155 hostname=<hostname>
156 set the initial hostname
157 rdblacklist=<drivername>
159 do not load kernel module <drivername> This parameter can be
160 specified multiple times.
161 rdloaddriver=<drivername>
163 force loading kernel module <drivername> This parameter can be
164 specified multiple times.
165 rd_retry=<seconds>
167 wait <seconds> until dracut tries to force assemble LVM or RAID
168 volumes. If the root device is not found within <seconds>*2 then
169 dracut fails and either drops to a shell, if rdshell is on the
170 kernel command line, or exits with 1, which normally causes a
171 kernel panic.
172 Default: rd_retry=40
174 Debug
177 rdinfo print informational output though "quiet" is set
178 rdshell
180 allow dropping to a shell, if root mounting fails
181 rdinitdebug
183 set -x for the dracut shell and logs to dmesg, console and
184 /init.log
185 rdbreak
187 drop to a shell at the end
188 rdbreak={cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount
190 |pre-pivot}
191 drop to a shell on defined breakpoint
192 rdudevinfo
194 set udev to loglevel info
195 rdudevdebug
197 set udev to loglevel debug
198 I18N
201 e.g.
202 LANG=en_US.UTF-8
203 SYSFONT=latarcyrheb-sun16
204 KEYTABLE=de-latin1-nodeadkeys
205 KEYBOARDTYPE=sun|pc
207 will be written to /etc/sysconfig/keyboard in the initramfs
208 KEYTABLE=<keytable filename>
210 will be written to /etc/sysconfig/keyboard in the initramfs
211 SYSFONT=Console font
213 will be written to /etc/sysconfig/i18n in the initramfs
214 SYSFONTACM=Unicode font map
216 will be written to /etc/sysconfig/i18n in the initramfs
217 UNIMAP=Unicode font map
219 will be written to /etc/sysconfig/i18n in the initramfs
220 LANG=<locale>
222 will be written to /etc/sysconfig/i18n in the initramfs
223 LVM
226 rd_NO_LVM
227 disable LVM detection
228 rd_LVM_VG=<volume group name>
230 only activate the volume groups with the given name rd_LVM_VG
231 can be specified multiple times on the kernel command line.
232 rd_LVM_LV=<logical volume name>
234 only activate the logical volumes with the given name rd_LVM_LV
235 can be specified multiple times on the kernel command line.
236 rd_NO_LVMCONF
238 remove any /etc/lvm/lvm.conf, which may exist in the initramfs
239 crypto LUKS
242 rd_NO_LUKS
243 disable crypto LUKS detection
244 rd_LUKS_UUID=<luks uuid>
246 only activate the LUKS partitions with the given UUID Any
247 "luks-" of the LUKS UUID is removed before comparing to <luks
248 uuid>. The comparisons also matches, if <luks uuid> is only the
249 beginning of the LUKS UUID, so you don't have to specify the
250 full UUID. This parameter can be specified multiple times.
251 rd_NO_CRYPTTAB
253 do not check, if LUKS partition is in /etc/crypttab
254 MD
257 rd_NO_MD
258 disable MD RAID detection
259 rd_NO_MDIMSM
261 no MD RAID for imsm/isw raids, use dmraid instead
262 rd_NO_MDADMCONF
264 ignore mdadm.conf included in initramfs
265 rd_MD_UUID=<md uuid>
267 only activate the raid sets with the given UUID. This parameter
268 can be specified multiple times.
269 DMRAID
272 rd_NO_DM
273 disable DM RAID detection
274 rd_DM_UUID=<dmraid uuid>
276 only activate the raid sets with the given UUID. This parameter
277 can be specified multiple times.
278 MULTIPATH
281 rd_NO_MULTIPATH
282 disable multipath in the initramfs
283 FIPS
286 fips=1 enable FIPS
287 boot=<bootdevice>
289 specify the device, where /boot is located
290 e.g.
291 boot=/dev/sda1
292 boot=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
293 boot=UUID=<uuid>
294 boot=LABEL=<label>
295 If the root device is encrypted, the /boot partition must reside
297 on a seperate partition and has to be specified.
298 Network
301 ip={dhcp|on|any|dhcp6|auto6|ibft}
302 dhcp|on|any: get ip from dhcp server from all interfaces. If
303 root=dhcp, loop sequentially through all interfaces (eth0, eth1,
304 ...) and use the first with a valid DHCP root-path.
305 auto6: IPv6 autoconfiguration
307 dhcp6: IPv6 DHCP
309 ibft: iBFT autoconfiguration
311 ip=<interface>:{dhcp|on|any|dhcp6|auto6}
314 dhcp|on|any|dhcp6: get ip from dhcp server on a specific inter‐
315 face auto6: do IPv6 autoconfiguration This parameter can be
316 specified multiple times.
317 ip=<client-IP>:[<server-id>]:<gateway-IP>:<netmask>:<clienthostname>
320 :<interface>:{none|off}
321 explicit network configuration. If you want do define a IPv6
322 address, put it in brackets (e.g. [2001:DB8::1]). This parame‐
323 ter can be specified multiple times.
324 ifname=<interface>:<MAC>
326 Assign network device name <interface> (ie eth0) to the NIC with
327 MAC <MAC>. Note that if you use this option you must specify an
328 ifname= argument for all interfaces used in ip= or fcoe= argu‐
329 ments This parameter can be specified multiple times.
330 bootdev=<interface>
332 specify network interface to use routing and netroot information
333 from. Required if multiple ip= lines are used.
334 nameserver=<IP> [nameserver=<IP> ...]
336 specify nameserver(s) to use
337 vlan=<vlanname>:<phydevice>
339 Setup vlan device named <vlanname> on <phydeivce>.
340 We support the four styles of vlan names: VLAN_PLUS_VID
341 (vlan0005), VLAN_PLUS_VID_NO_PAD (vlan5), DEV_PLUS_VID
342 (eth0.0005), DEV_PLUS_VID_NO_PAD (eth0.5) This parameter can be
343 specified multiple times.
344 bridge=<bridgename>:<ethnames>
346 Setup bridge <bridgename> with <ethnames>. <ethnames> is a
347 comma-separated list of physical (ethernet) interfaces. Bridge
348 without parameters assumes bridge=br0:eth0
349 bond=<bondname>[:<bondslaves>:[:<options>]]
351 Setup bonding device <bondname> on top of <bondslaves>. <bond‐
352 slaves> is a comma-separated list of physical (ethernet) inter‐
353 faces. <options> is a comma-separated list on bonding options
354 (modinfo bonding for details) in format compatible with
355 initscripts. If <options> includes multi-valued arp_ip_target
356 option, then its values should be separated by semicolon. Bond
357 without parameters assumes bond=bond0:eth0,eth1:mode=balance-rr
358 biosdevname={0|1]}
360 turn off/on biosdevname network interface renaming
361 NFS
363 root=[<server-ip>:]<root-dir>[:<nfs-options>]
364 mount nfs share from <server-ip>:/<root-dir>, if no server-ip is
365 given, use dhcp next_server. if server-ip is an IPv6 address it
366 has to be put in brackets, e.g. [2001:DB8::1]. NFS options can
367 be appended with the prefix ":" or "," and are seperated by ",".
368 root=nfs:[<server-ip>:]<root-dir>[:<nfs-options>]
370 root=nfs4:[<server-ip>:]<root-dir>[:<nfs-options>]
372 root=dhcp|dhcp6
374 root=dhcp alone directs initrd to look at the DHCP root-path
375 where NFS options can be specified.
376 root-path=<server-ip>:<root-dir>[,<nfs-options>]
377 root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
378 root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
379 root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
381 Deprecated! kernel Documentation/filesystems/nfsroot.txt defines
382 this method. This is supported by dracut but not recommended.
383 rd_NFS_DOMAIN=<NFSv4 domain name>
385 Set the NFSv4 domain name. Will overwrite the settings in
386 /etc/idmap.conf.
387 iSCSI
390 root=iscsi:[username:password[:reverse:password]@][<servername>]
391 :[<protocol>]:[<port>][:[<iscsi_iface_name>]:[<netdev_name>]]:[<LUN>]
392 :<targetname>
393 protocol defaults to "6", LUN defaults to "0".
394 If the "servername" field is provided by BOOTP or DHCP, then
396 that field is used in conjunction with other associated fields
397 to contact the boot server in the Boot stage (Section 7). How‐
398 ever, if the "servername" field is not provided, then the "tar‐
399 getname" field is then used in the Discovery Service stage in
400 conjunction with other associated fields.
401 http://tools.ietf.org/html/rfc4173
403 root=iscsi:[username:password[:reverse:password]@][<servername>]
406 :[<protocol>]:[<port>][:[<iscsi_iface_name>]:[<netdev_name>]]:[<LUN>]
407 :<targetname>
408 e.g. root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
409 If servername is an IPv6 address, it has to be put in brackets.
411 e.g.
412 root=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
413 root=??? netroot=iscsi:[username:password[:reverse:password]@]
415 [<servername>]:[<protocol>]:[<port>][:[<iscsi_iface_name>]:[<net‐
416 dev_name>]]:[<LUN>]:<targetname> ...
417 multiple netroot options allow setting up multiple iscsi disks
418 e.g.
419 root=UUID=12424547
420 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
421 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target1
422 If servername is an IPv6 address, it has to be put in brackets.
424 e.g.
425 netroot=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
426 root=??? iscsi_initiator=<initiator> iscsi_target_name=<target name>
428 iscsi_target_ip=<target ip> iscsi_target_port=<target port>
429 iscsi_target_group=<target group> iscsi_username=<username>
430 iscsi_password=<password> iscsi_in_username=<in username>
431 iscsi_in_password=<in password>
432 manually specify all iscsistart parameter (see iscsis‐
433 tart --help)
434 root=??? netroot=iscsi iscsi_firmware
437 will read the iscsi parameter from the BIOS firmware
438 iscsi_param=<param>
441 <param> will be passed as "--param <param>" to iscsistart. This
442 parameter can be specified multiple times.
443 e.g.:
444 "netroot=iscsi iscsi_firmware iscsi_param=node.ses‐
445 sion.timeo.replacement_timeout=30"
446 will result in
447 iscsistart -b --param node.session.timeo.replacement_time‐
448 out=30
449 FCoE
452 fcoe=<edd|interface|MAC>:<dcb|nodcb>
453 Try to connect to a FCoE SAN through the NIC specified by
454 <interface> or <MAC> or EDD settings. This parameter can be
455 specified multiple times.
456 NBD
459 root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
460 mount nbd share from <server>
461 root=dhcp
463 with dhcp root-path=nbd:<server>:<port>[:<fstype>][:<mountopts>]
464 root=dhcp alone directs initrd to look at the DHCP root-path
465 where NBD options can be specified. This syntax is only usable
466 in cases where you are directly mounting the volume as the
467 rootfs.
468 DASD
472 rd_DASD_MOD=....
473 same syntax as the kernel module parameter (s390 only)
474 rd_DASD=<dasd adaptor device bus ID>[,readonly=X][,use_diag=X]
477 [,erplog=X][,failfast=X]
478 activate DASD device with the given adaptor device bus ID and
479 setting the sysfs attributes to the specified values This param‐
480 eter can be specified multiple times.
481 ZFCP
484 rd_ZFCP=<zfcp adaptor device bus ID>,<WWPN>,<FCPLUN>
485 rd_ZFCP can be specified multiple times on the kernel command
486 line.
487 example: rd_ZFCP=0.0.4000,0x5005076300C213e9,0x5022000000000000
489 rd_NO_ZFCPCONF
491 ignore zfcp.conf included in the initramfs
492 ZNET
495 rd_ZNET=<nettype>,<subchannels>,<options>
496 rd_ZNET can be specified multiple times on the kernel command
497 line. Examples:
498 rd_ZNET=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,port‐
499 name=foo
500 rd_ZNET=ctc,0.0.0600,0.0.0601,0.0.0602,protocol=bar
501 Plymouth Boot Splash
504 rd_NO_PLYMOUTH
505 do not start plymouth. This will not work with encrypted parti‐
506 tions.
507
510 /var/log/dracut.log
511 /etc/dracut.conf
513 see dracut.conf(5)
514 Configuration in the Initramfs
516 /etc/conf.d/
517 Any files found in /etc/conf.d/ will be sourced in the initramfs
518 to set initial values. Command line options will override these
519 values set in the configuration files.
520 /etc/cmdline
522 Can contain additional command line options.
523
526 Harald Hoyer <harald@redhat.com>
527 Victor Lowther <victor.lowther@gmail.com>
528 Warren Togami <wtogami@redhat.com>
529 Jeremy Katz <katzj@redhat.com>
530 Philippe Seewer <philippe.seewer@bfh.ch>
531 David Dillow <dave@thedillows.org>
532
534 The dracut command is part of the dracut package and is available from
535 http://sourceforge.net/apps/trac/dracut/wiki
536
539 dracut.conf(5)
540Linux June 2009 DRACUT(8)