1 .TH DRACUT 8 "June 2009" "Linux"
3 switch_root \- switch to another filesystem as the root of the mount tree.
5 \fBdracut\fR [\fIOPTION\fR]... \fI<image>\fR \fI<kernel-version>\fR
9 \fBdracut\fR creates an initial image used by the kernel for
10 preloading the block device modules (such as IDE, SCSI or RAID)
11 which are needed to access the root filesystem.
15 .BR \-f ", " \-\-force
16 overwrite existing initramfs file.
18 .BR \-m ", " \-\-modules " \fILIST\fR"
19 specify a space-separated list of dracut modules to call
20 when building the initramfs.
21 Modules are located in
22 .IR /usr/share/dracut/modules.d .
24 .BR \-o ", " \-\-omit " \fILIST\fR"
25 omit a space-separated list of dracut modules.
27 .BR \-a ", " \-\-add " \fILIST\fR"
28 add a space-separated list of dracut modules.
30 .BR \-d ", " \-\-drivers " \fILIST\fR"
31 specify a space-separated list of kernel modules to include in the initramfs.
33 .BR \-k ", " \-\-kmoddir " \fI{DIR}\fR
34 specify the directory, where to look for kernel modules
36 .BR " \-\-fwdir " \fI{DIR}\fR
37 specify additional directory, where to look for firmwares
40 only install kernel drivers and firmware files
43 do not install kernel drivers and firmware files
46 display help text and exit.
49 output debug information of the build process
51 .BR \-v ", " \-\-verbose
52 verbose output during the build process
54 .BR \-c ", " \-\-conf " \fIFILE\fR"
55 specify configuration file to use.
59 .BR \-l ", " \-\-local
60 local mode. Use modules from the current working
61 directory instead of the system-wide installed in
62 .IR /usr/share/dracut/modules.d .
63 Useful when running dracut from a git checkout.
65 .BR \-H ", " \-\-hostonly
66 Host-Only mode: Install only what is needed for
67 booting the local host instead of a generic host.
69 .BR \-i ", " \-\-include " \fISOURCE\fR" "" " \fITARGET\fR"
70 include the files in the SOURCE directory into the
71 target directory in the final initramfs.
73 .BR \-I ", " \-\-install " \fILIST\fR"
74 install the space separated list of files into the initramfs.
76 .SH KERNEL COMMAND LINE
77 The root filesystem used by the kernel is specified in the boot configuration
78 file, as always. The traditional \fBroot=/dev/hda1\fR style device
79 specification is allowed. If a label is used, as in \fBroot=LABEL=rootPart\fR
80 the initrd will search all available devices for an ext2 or ext3 filesystem
81 with the appropriate label, and mount that device as the root filesystem.
82 \fBroot=UUID=uuidnumber\fR will mount the partition with that UUID as the
87 .B init=<path to real init>
89 .B root=<path to blockdevice>
90 specify e.g. \fI/dev/sda1\fR or
91 \fI/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1\fR
94 e.g. LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYTABLE=de-latin1-nodeadkeys
96 .B KEYBOARDTYPE=sun|pc
97 will be written to /etc/sysconfig/keyboard in the initramfs
99 .B KEYTABLE=<keytable filename>
100 will be written to /etc/sysconfig/keyboard in the initramfs
102 .B SYSFONT= Console font
103 will be written to /etc/sysconfig/i18n in the initramfs
105 .B SYSFONTACM= Unicode font map
106 will be written to /etc/sysconfig/i18n in the initramfs
108 .B UNIMAP= Unicode font map
109 will be written to /etc/sysconfig/i18n in the initramfs
112 will be written to /etc/sysconfig/i18n in the initramfs
114 .SH Bootsplash - plymouth
116 .B rd_plytheme=<theme name>
117 specify the plymouth bootsplash theme (fallback is text)
122 disable LVM detection
124 .B rd_LVM_VG=<volume group name>
125 only activate the volume groups with the given name
130 disable crypto LUKS detection
132 .B rd_LUKS_UUID=<luks uuid>
133 only activate the LUKS partitions with the given UUID
138 disable MD RAID detection
141 no MD RAID for imsm/isw raids, use dmraid instead
143 .B rd_MD_UUID=<md uuid>
144 only activate the raid sets with the given UUID
149 disable DM RAID detection
151 .B rd_DM_UUID=<dmraid uuid>
152 only activate the raid sets with the given UUID
157 same syntax as the kernel module parameter (s390 only)
162 get IP from dhcp server, root-path option from dhcp specifies root location
166 .B root=[<server-ip>:]<root-dir>[:<nfs-options>]
167 mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given,
168 use dhcp next_server.
169 NFS options can be appended with the prefix "." or ","
171 .B root=nfs:[<server-ip>:]<root-dir>[:<nfs-options>]
173 .B root=nfs4:[<server-ip>:]<root-dir>[:<nfs-options>]
176 root=dhcp alone directs initrd to look at the DHCP root-path where NFS
177 options can be specified.
178 root-path=<server-ip>:<root-dir>[,<nfs-options>]
179 root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
180 root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
182 .B root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
183 \fBDeprecated!\fR kernel Documentation/filesystems/nfsroot.txt defines
185 This is supported by dracut but not recommended.
189 .B root=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname>
190 protocol defaults to "6", LUN defaults to "0".
192 If the "servername" field is provided by BOOTP or DHCP, then that
193 field is used in conjunction with other associated fields to contact
194 the boot server in the Boot stage (Section 7). However, if the
195 "servername" field is not provided, then the "targetname" field is
196 then used in the Discovery Service stage in conjunction with other
199 http://tools.ietf.org/html/rfc4173
202 .B root=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname>
203 e.g. root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
206 .B root=??? netroot=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname> ...
207 multiple netroot options allow setting up multiple iscsi disks
209 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
210 .B not yet implemented
212 .B root=??? iscsi_initiator= iscsi_target_name= iscsi_target_ip= iscsi_target_port= iscsi_target_group= iscsi_username= iscsi_password= iscsi_in_username= iscsi_in_password=
215 .B root=??? iscsi_firmware
216 will read the iscsi parameter from the BIOS firmware
220 .B root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
221 mount nbd share from <server>
224 with dhcp root-path=nbd:<server>:<port>[:<fstype>][:<mountopts>]
225 root=dhcp alone directs initrd to look at the DHCP root-path where NBD options can be specified.
226 This syntax is only usable in cases where you are directly mounting the volume as the rootfs.
229 .TP bootdev=<interface>
230 .B specify the network interface to boot from
233 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.
235 .B ip=<interface>:{dhcp|on|any}
236 get ip from dhcp server on a specific interface
238 .B ip=<client-IP-number>:<gateway-IP-number>:<netmask>:<client-hostname>:<interface>:{none|off}
239 explicit network configuration
243 .B rdblacklist=<drivername>
244 do not load kernel module <drivername>
249 allow dropping to a shell, if root mounting fails
252 set -x for the dracut shell
255 drop to a shell at the end
257 .B rdbreak={pre-udev|pre-mount|mount|pre-pivot|commandline|initqueue}
258 drop to a shell on defined breakpoint
261 set udev to loglevel info
264 set udev to loglevel debug
267 debug network scripts in dracut. Output is written to /tmp/
269 .SH CONFIGURATION IN INITRAMFS
272 Any files found in /conf/conf.d/ will be sourced in the initramfs to
273 set initial values. Command line options will override these values
274 set in the configuration files.
278 Andreas Thienemann <andreas@bawue.net>
279 Bill Nottingham <notting@redhat.com>
280 Dave Jones <davej@redhat.com>
281 David Dillow <dave@thedillows.org>
282 Harald Hoyer <harald@redhat.com>
283 Jeremy Katz <katzj@redhat.com>
284 Peter Jones <pjones@redhat.com>
285 Seewer Philippe <philippe.seewer@bfh.ch>
286 Victor Lowther <victor.lowther@gmail.com>
287 Warren Togami <wtogami@redhat.com>
290 The dracut command is part of the dracut package and is available from
291 https://sourceforge.net/apps/trac/dracut/wiki