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.
34 display help text and exit.
37 output debug information of the build process
39 .BR \-v ", " \-\-verbose
40 verbose output during the build process
42 .BR \-c ", " \-\-conf " \fIFILE\fR"
43 specify configuration file to use.
47 .BR \-l ", " \-\-local
48 local mode. Use modules from the current working
49 directory instead of the system-wide installed in
50 .IR /usr/share/dracut/modules.d .
51 Useful when running dracut from a git checkout.
53 .BR \-H ", " \-\-hostonly
54 Host-Only mode: Install only what is needed for
55 booting the local host instead of a generic host.
57 .BR \-i ", " \-\-include " \fISOURCE\fR" "" " \fITARGET\fR"
58 include the files in the SOURCE directory into the
59 target directory in the final initramfs.
61 .BR \-I ", " \-\-install " \fILIST\fR"
62 install the space separated list of files into the initramfs.
64 .SH KERNEL COMMAND LINE
65 The root filesystem used by the kernel is specified in the boot configuration
66 file, as always. The traditional \fBroot=/dev/hda1\fR style device
67 specification is allowed. If a label is used, as in \fBroot=LABEL=rootPart\fR
68 the initrd will search all available devices for an ext2 or ext3 filesystem
69 with the appropriate label, and mount that device as the root filesystem.
70 \fBroot=UUID=uuidnumber\fR will mount the partition with that UUID as the
75 .B init=<path to real init>
77 .B root=<path to blockdevice>
78 specify e.g. \fI/dev/sda1\fR or
79 \fI/dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1\fR
82 e.g. LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYTABLE=de-latin1-nodeadkeys
84 .B KEYBOARDTYPE=sun|pc
85 will be written to /etc/sysconfig/keyboard in the initramfs
87 .B KEYTABLE=<keytable filename>
88 will be written to /etc/sysconfig/keyboard in the initramfs
90 .B SYSFONT= Console font
91 will be written to /etc/sysconfig/i18n in the initramfs
93 .B SYSFONTACM= Unicode font map
94 will be written to /etc/sysconfig/i18n in the initramfs
96 .B UNIMAP= Unicode font map
97 will be written to /etc/sysconfig/i18n in the initramfs
100 will be written to /etc/sysconfig/i18n in the initramfs
102 .SH Bootsplash - plymouth
104 .B rd_plytheme=<theme name>
105 specify the plymouth bootsplash theme (fallback is text)
110 disable LVM detection
112 .B rd_LVM_VG=<volume group name>
113 only activate the volume groups with the given name
118 disable crypto LUKS detection
120 .B rd_LUKS_UUID=<luks uuid>
121 only activate the LUKS partitions with the given UUID
126 disable MD RAID detection
128 .B rd_MD_UUID=<md uuid>
129 only activate the raid sets with the given UUID
134 disable DM RAID detection
136 .B rd_DM_UUID=<dmraid uuid>
137 only activate the raid sets with the given UUID
142 get IP from dhcp server, root-path option from dhcp specifies root location
146 .B root=[<server-ip>:]<root-dir>[:<nfs-options>]
147 mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given,
148 use dhcp next_server.
149 NFS options can be appended with the prefix "." or ","
151 .B root=nfs:[<server-ip>:]<root-dir>[:<nfs-options>]
153 .B root=nfs4:[<server-ip>:]<root-dir>[:<nfs-options>]
156 root=dhcp alone directs initrd to look at the DHCP root-path where NFS
157 options can be specified.
158 root-path=<server-ip>:<root-dir>[,<nfs-options>]
159 root-path=nfs:<server-ip>:<root-dir>[,<nfs-options>]
160 root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]
162 .B root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
163 \fBDeprecated!\fR kernel Documentation/filesystems/nfsroot.txt defines
165 This is supported by dracut but not recommended.
169 .B root=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname>
170 protocol defaults to "6", LUN defaults to "0".
172 If the "servername" field is provided by BOOTP or DHCP, then that
173 field is used in conjunction with other associated fields to contact
174 the boot server in the Boot stage (Section 7). However, if the
175 "servername" field is not provided, then the "targetname" field is
176 then used in the Discovery Service stage in conjunction with other
179 http://tools.ietf.org/html/rfc4173
182 .B root=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname>
183 e.g. root=iscsi:192.168.50.1::::iqn.2009-06.dracut:target0
186 .B root=??? netroot=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname> ...
187 multiple netroot options allow setting up multiple iscsi disks
189 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
190 .B not yet implemented
192 .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=
195 .B root=??? iscsi_firmware
196 will read the iscsi parameter from the BIOS firmware
200 .B root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
201 mount nbd share from <server>
204 with dhcp root-path=nbd:<server>:<port>[:<fstype>][:<mountopts>]
205 root=dhcp alone directs initrd to look at the DHCP root-path where NBD options can be specified.
206 This syntax is only usable in cases where you are directly mounting the volume as the rootfs.
209 .TP bootdev=<interface>
210 .B specify the network interface to boot from
213 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.
215 .B ip=<interface>:[dhcp|on|any]
216 get ip from dhcp server on a specific interface
218 .B ip=<client-IP-number>:<gateway-IP-number>:<netmask>:<client-hostname>:<interface>:[dhcp|on|any|]
219 explicit network configuration
223 .B rdblacklist=<drivername>
224 do not load kernel module <drivername>
229 drop to a shell, if the imitramfs fails
232 set -x for the dracut shell
234 .B rdbreak=[pre-udev|pre-mount|mount|pre-pivot|]
235 drop the shell on defined breakpoint
238 set udev to loglevel info
241 set udev to loglevel debug
244 debug network scripts in dracut. Output is written to /tmp/
246 .SH CONFIGURATION IN INITRAMFS
249 Any files found in /conf/conf.d/ will be sourced in the initramfs to
250 set initial values. Command line options will override these values
251 set in the configuration files.
255 Andreas Thienemann <andreas@bawue.net>
256 Bill Nottingham <notting@redhat.com>
257 Dave Jones <davej@redhat.com>
258 David Dillow <dave@thedillows.org>
259 Harald Hoyer <harald@redhat.com>
260 Jeremy Katz <katzj@redhat.com>
261 Peter Jones <pjones@redhat.com>
262 Seewer Philippe <philippe.seewer@bfh.ch>
263 Victor Lowther <victor.lowther@gmail.com>
264 Warren Togami <wtogami@redhat.com>
267 The dracut command is part of the dracut package and is available from
268 https://sourceforge.net/apps/trac/dracut/wiki