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= Options =  
= Options =  
 
==-f, --force==
<pre>-f, --force</pre>
<pre>-f, --force</pre>
{{admon/note|Overwrite existing initramfs file.}}
{{admon/note|Overwrite existing initramfs file.}}
==-m, --modules==
<pre>-m, --modules LIST</pre>
<pre>-m, --modules LIST</pre>
{{admon/note|Specify a space-separated list of dracut modules to call when building the initramfs.  Modules are located in /usr/share/dracut/modules.d.}}
{{admon/note|Specify a space-separated list of dracut modules to call when building the initramfs.  Modules are located in /usr/share/dracut/modules.d.}}
==-o, --omit==
<pre>-o, --omit LIST</pre>
<pre>-o, --omit LIST</pre>
{{admon/note|Omit a space-separated list of dracut modules.}}
{{admon/note|Omit a space-separated list of dracut modules.}}
==-a, --add==
<pre>-a, --add LIST</pre>
<pre>-a, --add LIST</pre>
{{admon/note|Add a space-separated list of dracut modules.}}
{{admon/note|Add a space-separated list of dracut modules.}}
==-d, --drivers==
<pre>-d, --drivers LIST</pre>
<pre>-d, --drivers LIST</pre>
{{admon/note|Specify a space-separated list of kernel modules to include in the initramfs.}}
{{admon/note|Specify a space-separated list of kernel modules to include in the initramfs.}}
==-h, --help==
<pre>-h, --help</pre>
<pre>-h, --help</pre>
{{admon/note|Display help text and exit.}}
{{admon/note|Display help text and exit.}}
==--debug==
<pre>--debug</pre>
<pre>--debug</pre>
{{admon/note|Output debug information of the build process}}
{{admon/note|Output debug information of the build process}}
==v, --verbose==
<pre>v, --verbose</pre>
<pre>v, --verbose</pre>
{{admon/note|Verbose output during the build process}}
{{admon/note|Verbose output during the build process}}
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<pre>-i, --include SOURCE TARGET</pre>
<pre>-i, --include SOURCE TARGET</pre>
{{admon/note|Include the files in the SOURCE directory into the target directory in the final initramfs.}}
{{admon/note|Include the files in the SOURCE directory into the target directory in the final initramfs.}}
== -I, --install ===
== -I, --install ==
</pre>-I, --install LIST</pre>
</pre>-I, --install LIST</pre>
{{admon/note|Install the space separated list of files into the initramfs.}}
{{admon/note|Install the space separated list of files into the initramfs.}}

Revision as of 16:13, 17 July 2009


Options

-f, --force

-f, --force
Note.png
Overwrite existing initramfs file.

-m, --modules

-m, --modules LIST
Note.png
Specify a space-separated list of dracut modules to call when building the initramfs. Modules are located in /usr/share/dracut/modules.d.

-o, --omit

-o, --omit LIST
Note.png
Omit a space-separated list of dracut modules.

-a, --add

-a, --add LIST
Note.png
Add a space-separated list of dracut modules.

-d, --drivers

-d, --drivers LIST
Note.png
Specify a space-separated list of kernel modules to include in the initramfs.

-h, --help

-h, --help
Note.png
Display help text and exit.

--debug

--debug
Note.png
Output debug information of the build process

v, --verbose

v, --verbose
Note.png
Verbose output during the build process

-c, --conf

-c, --conf FILE
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Specify configuration file to use. Default: /etc/dracut.conf

-l, --local

-l, --local
Note.png
Local mode. Use modules from the current working directory instead of the system-wide installed in /usr/share/dracut/modules.d. Useful when running dracut from a git checkout.

-H, --hostonly

-H, --hostonly
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Host-Only mode: Install only what is needed for booting the local host instead of a generic host.

-i, --include

-i, --include SOURCE TARGET
Note.png
Include the files in the SOURCE directory into the target directory in the final initramfs.

-I, --install

-I, --install LIST

Note.png
Install the space separated list of files into the initramfs.

Dracut kernel command line parameters

The root filesystem used by the kernel is specified in the boot configuration 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.

Limitations

  • Command line length: 2048
  • dhcp root-path: 255



Standard

init=<path to real init>
root=<path to blockdevice>
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Specify e.g. /dev/sda1 or /dev/disk/by-path/pci-0000:00:1f.1-scsi-0:0:1:0-part1

DHCP

root=dhcp
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Get IP from dhcp server, root-path option from dhcp specifies root location.

NFSv3

root=[<server-ip>:]<root-dir>[:<nfs-options>]
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Mount nfs share from <server-ip>:/<root-dir> If no server-ip is given use dhcp next_server. nfs-options can be appended with the prefix ":" or ","
root=dhcp
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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>]

Deprecated

root=/dev/nfs nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
Note.png
Kernel Documentation/filesystems/nfsroot.txt defines this method. This is supported by dracut but not recommended.

NFSv4

root=nfs4:[<server-ip>:]<root-dir>[:<nfs-options>]
Note.png
mount nfsv4 share from <server-ip>:/<root-dir>. If no server-ip is given, use dhcp next_server. nfs-options can be appended with the prefix ":" or ","
root=dhcp
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root-path=nfs4:<server-ip>:<root-dir>[,<nfs-options>]. root=dhcp alone directs initrd to look at the DHCP root-path where NFS options can be specified.

iSCSI

root=iscsi:[<servername>]:[<protocol>]:[<port>]:[<LUN>]:<targetname>::
Note.png
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). However, if the "servername" field is not provided, then the "targetname" field is then used in the Discovery Service stage in conjunction with other associated fields.RFC4173
root=??? iscsiroot=...::
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=::
root=??? iscsi_firmware::

NBD

root=nbd:<server>:<port>[:<fstype>][:<mountopts>]
Note.png
Mount nbd share from <server>.
root=dhcp
Note.png
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.

Network

ip=[dhcp|on|any]
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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.
ip=<interface>:[dhcp|on|any]
Note.png
Get ip from dhcp server on a specific interface.
ip=<client-IP-number>:<gateway-IP-number>:<netmask>:<client-hostname>:<interface>:[dhcp|on|any|]
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Explicit network configuration

Misc

rdblacklist=<modulename>
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TBD: do not load modulename.

Debug

rdinitdebug
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Drop to a shell, if the imitramfs fails.
rdinitdebug
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set -x for the dracut shell.
rdbreak=[pre-udev|pre-mount|mount|pre-pivot|]
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Drop the shell on defined breakpoint.
rdudevinfo
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Set udev to loglevel info.
rdudevdebug
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Set udev to loglevel debug.
rdnetdebug
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Debug network scripts in dracut.

Configuration in initrd

/conf/conf.d/* 
Note.png
Command line options can override values set here