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 --filesystems LIST
44 specify a space-separated list of kernel filesystem modules to
45 exclusively include in the generic initramfs.
46 -k, --kmoddir {DIR}
48 specify the directory, where to look for kernel modules
49 --fwdir {DIR}
51 specify additional directory, where to look for firmwares
52 --kernel-only
54 only install kernel drivers and firmware files
55 --no-kernel
57 do not install kernel drivers and firmware files
58 --mdadmconf
60 include local /etc/mdadm.conf
61 --nomdadmconf
63 do not include local /etc/mdadm.conf
64 --strip
66 strip binaries in the initramfs (default)
67 --nostrip
69 do not strip binaries in the initramfs
70 -h, --help
72 display help text and exit.
73 --debug
75 output debug information of the build process
76 -v, --verbose
78 verbose output during the build process
79 -c, --conf FILE
81 specify configuration file to use. Default: /etc/dracut.conf
82 --confdir DIR
84 specify configuration directory to use. Default: /etc/dra‐
85 cut.conf.d
86 -l, --local
88 local mode. Use modules from the current working directory
89 instead of the system-wide installed in /usr/share/dracut/mod‐
90 ules.d. Useful when running dracut from a git checkout.
91 -H, --hostonly
93 Host-Only mode: Install only what is needed for booting the
94 local host instead of a generic host.
95 -i, --include SOURCE TARGET
97 include the files in the SOURCE directory into the target direc‐
98 tory in the final initramfs.
99 -I, --install LIST
101 install the space separated list of files into the initramfs.
102
105 The root filesystem used by the kernel is specified in the boot config‐
106 uration file, as always. The traditional root=/dev/hda1 style device
107 specification is allowed. If a label is used, as in root=LABEL=rootPart
108 the initrd will search all available devices for an ext2 or ext3
109 filesystem with the appropriate label, and mount that device as the
110 root filesystem. root=UUID=uuidnumber will mount the partition with
111 that UUID as the root filesystem.
112 Standard
115 init=<path to real init>
116 root=<path to blockdevice>
118 specify blockdevice to use as root filesystem.
119 e.g.
120 root=/dev/sda1
121 root=/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1
122 rootfstype=<filesystem type>
124 "auto" if not specified, e.g. rootfstype=ext3
125 rootflags=<mount options>
127 specify additional mount options for the root filesystem. If not
128 set, /etc/fstab of the real root will be parsed for special
129 mount options and mounted accordingly.
130 rd_NO_FSTAB
132 do not honor special mount options for the root filesystem found
133 in /etc/fstab of the real root.
134 Misc
137 rdblacklist=<drivername>
138 do not load kernel module <drivername> This parameter can be
139 specified multiple times.
140 rdloaddriver=<drivername>
142 force loading kernel module <drivername> This parameter can be
143 specified multiple times.
144 Debug
147 rdinfo print informational output though "quiet" is set
148 rdshell
150 allow dropping to a shell, if root mounting fails
151 rdinitdebug
153 set -x for the dracut shell and logs to dmesg, console and
154 /init.log
155 rdbreak
157 drop to a shell at the end
158 rdbreak={cmdline|pre-udev|pre-trigger|initqueue|pre-mount|mount
160 |pre-pivot}
161 drop to a shell on defined breakpoint
162 rdudevinfo
164 set udev to loglevel info
165 rdudevdebug
167 set udev to loglevel debug
168 I18N
171 e.g.
172 LANG=en_US.UTF-8
173 SYSFONT=latarcyrheb-sun16
174 KEYTABLE=de-latin1-nodeadkeys
175 KEYBOARDTYPE=sun|pc
177 will be written to /etc/sysconfig/keyboard in the initramfs
178 KEYTABLE=<keytable filename>
180 will be written to /etc/sysconfig/keyboard in the initramfs
181 SYSFONT=Console font
183 will be written to /etc/sysconfig/i18n in the initramfs
184 SYSFONTACM=Unicode font map
186 will be written to /etc/sysconfig/i18n in the initramfs
187 UNIMAP=Unicode font map
189 will be written to /etc/sysconfig/i18n in the initramfs
190 LANG=<locale>
192 will be written to /etc/sysconfig/i18n in the initramfs
193 LVM
196 rd_NO_LVM
197 disable LVM detection
198 rd_LVM_VG=<volume group name>
200 only activate the volume groups with the given name rd_LVM_VG
201 can be specified multiple times on the kernel command line.
202 rd_LVM_LV=<logical volume name>
204 only activate the logical volumes with the given name rd_LVM_LV
205 can be specified multiple times on the kernel command line.
206 rd_NO_LVMCONF
208 remove any /etc/lvm/lvm.conf, which may exist in the initramfs
209 crypto LUKS
212 rd_NO_LUKS
213 disable crypto LUKS detection
214 rd_LUKS_UUID=<luks uuid>
216 only activate the LUKS partitions with the given UUID Any
217 "luks-" of the LUKS UUID is removed before comparing to <luks
218 uuid>. The comparisons also matches, if <luks uuid> is only the
219 beginning of the LUKS UUID, so you don't have to specify the
220 full UUID. This parameter can be specified multiple times.
221 rd_NO_CRYPTTAB
223 do not check, if LUKS partition is in /etc/crypttab
224 MD
227 rd_NO_MD
228 disable MD RAID detection
229 rd_NO_MDIMSM
231 no MD RAID for imsm/isw raids, use dmraid instead
232 rd_NO_MDADMCONF
234 ignore mdadm.conf included in initramfs
235 rd_MD_UUID=<md uuid>
237 only activate the raid sets with the given UUID. This parameter
238 can be specified multiple times.
239 DMRAID
242 rd_NO_DM
243 disable DM RAID detection
244 rd_DM_UUID=<dmraid uuid>
246 only activate the raid sets with the given UUID. This parameter
247 can be specified multiple times.
248 Network
251 ip={dhcp|on|any|dhcp6|auto6}
252 dhcp|on|any: get ip from dhcp server from all interfaces. If
253 root=dhcp, loop sequentially through all interfaces (eth0, eth1,
254 ...) and use the first with a valid DHCP root-path.
255 auto6: do IPv6 autoconfiguration
257 ip=<interface>:{dhcp|on|any|dhcp6|auto6}
259 dhcp|on|any|dhcp6: get ip from dhcp server on a specific inter‐
260 face auto6: do IPv6 autoconfiguration This parameter can be
261 specified multiple times.
262 ip=<client-IP>:[<server-id>]:<gateway-IP>:<netmask>:<clienthostname>
265 :<interface>:{none|off}
266 explicit network configuration. If you want do define a IPv6
267 address, put it in brackets (e.g. [2001:DB8::1]). This parame‐
268 ter can be specified multiple times.
269 ifname=<interface>:<MAC>
271 Assign network device name <interface> (ie eth0) to the NIC with
272 MAC <MAC>. Note letters in the MAC-address must be lowercase!
273 Note that if you use this option you must specify an ifname=
274 argument for all interfaces used in ip= or fcoe= arguments This
275 parameter can be specified multiple times.
276 bootdev=<interface>
278 specify network interface to use routing and netroot information
279 from. Required if multiple ip= lines are used.
280 nameserver=<IP> [nameserver=<IP> ...]
282 specify nameserver(s) to use
283 NFS
286 root=[<server-ip>:]<root-dir>[:<nfs-options>]
287 mount nfs share from <server-ip>:/<root-dir>, if no server-ip is
288 given, use dhcp next_server. if server-ip is an IPv6 address it
289 has to be put in brackets, e.g. [2001:DB8::1]. NFS options can
290 be appended with the prefix ":" or "," and are seperated by ",".
291 root=nfs:[<server-ip>:]<root-dir>[:<nfs-options>]
293 root=nfs4:[<server-ip>:]<root-dir>[:<nfs-options>]
295 root=dhcp|dhcp6
297 root=dhcp alone directs initrd to look at the DHCP root-path
298 where NFS options can be specified.
299 root-path=<server-ip>:<root-dir>[,<nfs-options>]
300 root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
301 root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
302 root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
304 Deprecated! kernel Documentation/filesystems/nfsroot.txt defines
305 this method. This is supported by dracut but not recommended.
306 rd_NFS_DOMAIN=<NFSv4 domain name>
308 Set the NFSv4 domain name. Will overwrite the settings in
309 /etc/idmap.conf.
310 iSCSI
313 root=iscsi:[username:password[:reverse:password]@][<servername>]
314 :[<protocol>]:[<port>]:[<LUN>]:<targetname>
315 protocol defaults to "6", LUN defaults to "0".
316 If the "servername" field is provided by BOOTP or DHCP, then
318 that field is used in conjunction with other associated fields
319 to contact the boot server in the Boot stage (Section 7). How‐
320 ever, if the "servername" field is not provided, then the "tar‐
321 getname" field is then used in the Discovery Service stage in
322 conjunction with other associated fields.
323 http://tools.ietf.org/html/rfc4173
325 root=iscsi:[username:password[:reverse:password]@][<servername>]
328 :[<protocol>]:[<port>]:[<LUN>]:<targetname>
329 e.g. root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
330 If servername is an IPv6 address, it has to be put in brackets.
332 e.g.
333 root=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
334 root=??? netroot=iscsi:[username:password[:reverse:password]@]
336 [<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname> ...
337 multiple netroot options allow setting up multiple iscsi disks
338 e.g.
339 root=UUID=12424547
340 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
341 netroot=iscsi:192.168.50.1::::iqn.2009-06.dracut:target1
342 If servername is an IPv6 address, it has to be put in brackets.
344 e.g.
345 netroot=iscsi:[2001:DB8::1]::::iqn.2009-06.dracut:target0
346 root=??? iscsi_initiator=<initiator> iscsi_target_name=<target name>
348 iscsi_target_ip=<target ip> iscsi_target_port=<target port>
349 iscsi_target_group=<target group> iscsi_username=<username>
350 iscsi_password=<password> iscsi_in_username=<in username>
351 iscsi_in_password=<in password>
352 manually specify all iscsistart parameter (see iscsis‐
353 tart --help)
354 root=??? iscsi_firmware
357 will read the iscsi parameter from the BIOS firmware
358 FCoE
361 netroot=fcoe:<interface|MAC>:<dcb|nodcb>
362 Try to connect to a FCoE SAN through the NIC specified by
363 <interface> or <MAC>, for the second argument, currently only
364 nodcb is supported. Note letters in the MAC-address must be low‐
365 ercase!
366 NBD
369 root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
370 mount nbd share from <server>
371 root=dhcp
373 with dhcp root-path=nbd:<server>:<port>[:<fstype>][:<mountopts>]
374 root=dhcp alone directs initrd to look at the DHCP root-path
375 where NBD options can be specified. This syntax is only usable
376 in cases where you are directly mounting the volume as the
377 rootfs.
378 DASD
382 rd_DASD_MOD=....
383 same syntax as the kernel module parameter (s390 only)
384 rd_DASD=<dasd adaptor device bus ID>[,readonly=X][,use_diag=X]
387 [,erplog=X][,failfast=X]
388 activate DASD device with the given adaptor device bus ID and
389 setting the sysfs attributes to the specified values This param‐
390 eter can be specified multiple times.
391 ZFCP
394 rd_ZFCP=<zfcp adaptor device bus ID>,<WWPN>,<FCPLUN>
395 rd_ZFCP can be specified multiple times on the kernel command
396 line.
397 example: rd_ZFCP=0.0.4000,0x5005076300C213e9,0x5022000000000000
399 rd_NO_ZFCPCONF
401 ignore zfcp.conf included in the initramfs
402 ZNET
405 rd_ZNET=<nettype>,<subchannels>,<options>
406 rd_ZNET can be specified multiple times on the kernel command
407 line. Examples:
408 rd_ZNET=qeth,0.0.0600,0.0.0601,0.0.0602,layer2=1,port‐
409 name=foo
410 rd_ZNET=ctc,0.0.0600,0.0.0601,0.0.0602,protocol=bar
411 Plymouth Boot Splash
414 rd_NO_PLYMOUTH
415 do not start plymouth. This will not work with encrypted parti‐
416 tions.
417
420 /var/log/dracut.log
421 /tmp/dracut.log
423 see dracut.conf(5)
424 /etc/dracut.conf
426 Configuration in the Initramfs
428 /conf/conf.d/
429 Any files found in /conf/conf.d/ will be sourced in the
430 initramfs to set initial values. Command line options will over‐
431 ride these values set in the configuration files.
432 /etc/cmdline
434 Can contain additional command line options.
435
438 Harald Hoyer <harald@redhat.com>
439 Victor Lowther <victor.lowther@gmail.com>
440 Warren Togami <wtogami@redhat.com>
441 Jeremy Katz <katzj@redhat.com>
442 Philippe Seewer <philippe.seewer@bfh.ch>
443 David Dillow <dave@thedillows.org>
444
446 The dracut command is part of the dracut package and is available from
447 http://sourceforge.net/apps/trac/dracut/wiki
448
451 dracut.conf(5)
452Linux June 2009 DRACUT(8)