Standard
~~~~~~~~
**init=**__<path to real init>__::
- specify the path to the init programm to be started after the initramfs has
+ specify the path to the init program to be started after the initramfs has
finished
**root=**__<path to blockdevice>__::
Misc
~~~~
+**rd.emergency=**__[reboot|poweroff|halt]__::
+ specify, what action to execute in case of a critical failure. rd.shell=0 also
+ be specified.
+
**rd.driver.blacklist=**__<drivername>__[,__<drivername>__,...]::
do not load kernel module <drivername>. This parameter can be specified
multiple times.
_/run/initramfs/init.log_.
If "quiet" is set, it also logs to the console.
-**rd.memdebug=[0-3]**::
- Print memory usage info at various points, set the verbose level from 0 to 3.
+**rd.memdebug=[0-4]**::
+ Print memory usage info at various points, set the verbose level from 0 to 4.
+
Higher level means more debugging output:
+
1 - partial /proc/meminfo
2 - /proc/meminfo
3 - /proc/meminfo + /proc/slabinfo
+ 4 - /proc/meminfo + /proc/slabinfo + tracekomem
+ NOTE: tracekomem is a shell script utilizing kernel trace to track
+ the rough total memory consumption of kernel modules during
+ loading. It may override other trace configurations.
----
**rd.break**::
**rd.luks.crypttab=0**::
do not check, if LUKS partition is in _/etc/crypttab_
+**rd.luks.timeout=**__<seconds>__::
+ specify how long dracut should wait when waiting for the user to enter the
+ password. This avoid blocking the boot if no password is entered. It does
+ not apply to luks key. The default is '0', which means 'forever'.
+
crypto LUKS - key on removable device support
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
**rd.luks.key=**__<keypath>__:__<keydev>__:__<luksdev>__::
* enp0s29u1u2
=====================
-**ip=**__{dhcp|on|any|dhcp6|auto6}__::
+**ip=**__{dhcp|on|any|dhcp6|auto6|either6}__::
dhcp|on|any::: 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.
dhcp6::: IPv6 DHCP
+ either6::: if auto6 fails, then dhcp6
+
**ip=**__<interface>__:__{dhcp|on|any|dhcp6|auto6}__[:[__<mtu>__][:__<macaddr>__]]::
This parameter can be specified multiple times.
+
same <interface>.
=====================
-**ip=**__<client-IP>__:[__<peer>__]:__<gateway-IP>__:__<netmask>__:__<client_hostname>__:__<interface>__:__{none|off|dhcp|on|any|dhcp6|auto6|ibft}__:[:[__<mtu>__][:__<macaddr>__]]::
+**ip=**__<client-IP>__:[__<peer>__]:__<gateway-IP>__:__<netmask>__:__<client_hostname>__:__<interface>__:__{none|off|dhcp|on|any|dhcp6|auto6|ibft}__[:[__<mtu>__][:__<macaddr>__]]::
explicit network configuration. If you want do define a IPv6 address, put it
in brackets (e.g. [2001:DB8::1]). This parameter can be specified multiple
times. __<peer>__ is optional and is the address of the remote endpoint
VLAN_PLUS_VID_NO_PAD (vlan5), DEV_PLUS_VID (eth0.0005),
DEV_PLUS_VID_NO_PAD (eth0.5)
-**bond=**__<bondname>__[:__<bondslaves>__:[:__<options>__]]::
+**bond=**__<bondname>__[:__<bondslaves>__:[:__<options>__[:<mtu>]]]::
Setup bonding device <bondname> on top of <bondslaves>.
<bondslaves> is a comma-separated list of physical (ethernet) interfaces.
<options> is a comma-separated list on bonding options (modinfo bonding for
details) in format compatible with initscripts. If <options> includes
multi-valued arp_ip_target option, then its values should be separated by
- semicolon. Bond without parameters assumes
+ semicolon. if the mtu is specified, it will be set on the bond master.
+ Bond without parameters assumes
bond=bond0:eth0,eth1:mode=balance-rr
**team=**__<teammaster>__:__<teamslaves>__::
mount nfs share from <server-ip>:/<root-dir>, if no server-ip is given, use
dhcp next_server. If server-ip is an IPv6 address it has to be put in
brackets, e.g. [2001:DB8::1]. NFS options can be appended with the prefix
- ":" or "," and are seperated by ",".
+ ":" or "," and are separated by ",".
**root=**nfs:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**nfs4:\[_<server-ip>_:]__<root-dir>__[:__<nfs-options>__], **root=**__{dhcp|dhcp6}__::
root=dhcp alone directs initrd to look at the DHCP root-path where NFS
method. This is supported by dracut, but not recommended.
**rd.nfs.domain=**__<NFSv4 domain name>__::
- Set the NFSv4 domain name. Will overwrite the settings in _/etc/idmap.conf_.
+ Set the NFSv4 domain name. Will override the settings in _/etc/idmap.conf_.
**rd.net.dhcp.retry=**__<cnt>__::
If this option is set, dracut will try to connect via dhcp <cnt> times before failing.
**root=**_???_ **netroot=**iscsi **rd.iscsi.firmware=1**::
will read the iscsi parameter from the BIOS firmware
+**rd.iscsi.login_retry_max=**__<num>__::
+ maximum number of login retries
+
**rd.iscsi.param=**__<param>__::
<param> will be passed as "--param <param>" to iscsistart.
This parameter can be specified multiple times.
FCoE
~~~~
-**fcoe=**__<edd|interface|MAC>__:__{dcb|nodcb}__::
+**rd.nofcoe=0**::
+ disable FCoE and lldpad
+
+**fcoe=**__<edd|interface|MAC>__:__{dcb|nodcb}__:__{fabric|vn2vn}__::
Try to connect to a FCoE SAN through the NIC specified by _<interface>_ or
- _<MAC>_ or EDD settings. For the second argument, currently only nodcb is
- supported. This parameter can be specified multiple times.
+ _<MAC>_ or EDD settings. The second argument specifies if DCB
+ should be used. The optional third argument specifies whether
+ fabric or VN2VN mode should be used.
+ This parameter can be specified multiple times.
+
NOTE: letters in the MAC-address must be lowercase!
NBD
~~~
-**root=**??? **netroot=**nbd:__<server>__:__<port>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
- mount nbd share from <server>
+**root=**??? **netroot=**nbd:__<server>__:__<port/exportname>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
+ mount nbd share from <server>.
++
+NOTE:
+ If "exportname" instead of "port" is given the standard port is used.
+ Newer versions of nbd are only supported with "exportname".
-**root=dhcp** with **dhcp** **root-path=**nbd:__<server>__:__<port>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
+**root=dhcp** with **dhcp** **root-path=**nbd:__<server>__:__<port/exportname>__[:__<fstype>__[:__<mountopts>__[:__<nbdopts>__]]]::
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.
++
+NOTE:
+ If "exportname" instead of "port" is given the standard port is used.
+ Newer versions of nbd are only supported with "exportname".
DASD
~~~~
ZFCP
~~~~
**rd.zfcp=**__<zfcp adaptor device bus ID>__,__<WWPN>__,__<FCPLUN>__::
- rd.zfcp can be specified multiple times on the kernel command line.
+ rd.zfcp can be specified multiple times on the kernel command
+ line.
+
+**rd.zfcp=**__<zfcp adaptor device bus ID>__::
+ If NPIV is enabled and the 'allow_lun_scan' parameter to the zfcp
+ module is set to 'Y' then the zfcp adaptor will be initiating a
+ scan internally and the <WWPN> and <FCPLUN> parameters can be omitted.
+
[listing]
.Example
--
rd.zfcp=0.0.4000,0x5005076300C213e9,0x5022000000000000
+rd.zfcp=0.0.4000
--
**rd.zfcp.conf=0**::
ZNET
~~~~
**rd.znet=**__<nettype>__,__<subchannels>__,__<options>__::
+ The whole parameter is appended to /etc/ccw.conf, which is used on
+ RHEL/Fedora with ccw_init, which is called from udev for certain
+ devices on z-series.
rd.znet can be specified multiple times on the kernel command line.
+
[listing]
Dracut offers multiple options for live booted images:
=====================
-SquashFS with read-only filesystem image::: The system will boot with a read
-only filesystem from the SquashFS and apply a writable device-mapper snapshot
-over the read only filesystem. Using this method ensures a relatively fast
-boot and lower RAM usage. Users **must be careful** to avoid writing too many
-blocks to the snapshot volume. Once the blocks of the snapshot overlay are
-exhausted, the root filesystem becomes unusable and requires a reboot. A
-persistent overlay is marked Invalid, and requires a difficult recovery.
-Non-persistent overlays default to 512 MiB in RAM, but the size can be adjusted
-with the **rd.live.overlay.size=** kernel command line option.
+SquashFS with read-only filesystem image::: The system will boot with a
+read-only filesystem from the SquashFS and apply a writable Device-mapper
+snapshot or an OverlayFS overlay mount for the read-only base filesystem. This
+method ensures a relatively fast boot and lower RAM usage. Users **must be
+careful** to avoid writing too many blocks to a snapshot volume. Once the
+blocks of the snapshot overlay are exhausted, the root filesystem becomes
+read-only and may cause application failures. The snapshot overlay file is
+marked 'Overflow', and a difficult recovery is required to repair and enlarge
+the overlay offline. Non-persistent overlays are sparse files in RAM that only
+consume content space as required blocks are allocated. They default to an
+apparent size of 32 GiB in RAM. The size can be adjusted with the
+**rd.live.overlay.size=** kernel command line option.
+
-The filesystem structure is expected to be:
+The filesystem structure is traditionally expected to be:
+
[listing]
--
-squashfs.img | Squashfs from LiveCD .iso downloaded via network
+squashfs.img | SquashFS from LiveCD .iso
!(mount)
/LiveOS
- |- ext3fs.img | Filesystem image to mount read-only
+ |- rootfs.img | Filesystem image to mount read-only
!(mount)
/bin | Live filesystem
/boot |
... |
--
+
-Dracut uses this method of live booting by default. No additional command line
-options are required other than **root=live:<URL>** to specify the location
-of your squashed filesystem.
+For OverlayFS mount overlays, the filesystem structure may also be a direct
+compression of the root filesystem:
++
+[listing]
+--
+squashfs.img | SquashFS from LiveCD .iso
+ !(mount)
+ /bin | Live filesystem
+ /boot |
+ /dev |
+ ... |
+--
++
+Dracut uses one of the overlay methods of live booting by default. No
+additional command line options are required other than **root=live:<URL>** to
+specify the location of your squashed filesystem.
+
- The compressed SquashFS image can be copied during boot to RAM at
`/run/initramfs/squashed.img` by using the **rd.live.ram=1** option.
-- A device with a persistent overlay can be booted read only by using the
+- A device with a persistent overlay can be booted read-only by using the
**rd.live.overlay.readonly** option on the kernel command line. This will
-cause a temporary, writable overlay to be stacked over a read-only snapshot
-of the root filesystem.
+either cause a temporary, writable overlay to be stacked over a read-only
+snapshot of the root filesystem or the OverlayFS mount will use an additional
+lower layer with the root filesystem.
+
Uncompressed live filesystem image:::
When the live system was installed with the '--skipcompress' option of the
__livecd-iso-to-disk__ installation script for Live USB devices, the root
-filesystem image, `ext3fs.img`, is expanded on installation and no SquashFS
+filesystem image, __rootfs.img__, is expanded on installation and no SquashFS
is involved during boot.
+
- If **rd.live.ram=1** is used in this situation, the full, uncompressed
`/run` tmpfs.
+
- If **rd.live.overlay=none** is provided as a kernel command line option,
-a writable, linear device-mapper target is created on boot with no overlay.
+a writable, linear Device-mapper target is created on boot with no overlay.
-writable filesystem image:::
+Writable filesystem image:::
The system will retrieve a compressed filesystem image, extract it to
`/run/initramfs/fsimg/rootfs.img`, connect it to a loop device, create a
-writable, linear device-mapper target at `/dev/mapper/live-rw`, and mount that
+writable, linear Device-mapper target at `/dev/mapper/live-rw`, and mount that
as a writable volume at `/`. More RAM is required during boot but the live
filesystem is easier to manage if it becomes full. Users can make a filesystem
image of any size and that size will be maintained when the system boots. There
+
[listing]
--
-rootfs.tgz | Compressed tarball containing fileystem image
+rootfs.tgz | Compressed tarball containing filesystem image
!(unpack)
/rootfs.img | Filesystem image at /run/initramfs/fsimg/
!(mount)
This method is very suitable for diskless boots.
**root=**live:__<url>__::
-Boots a live image retrieved from __<url>__. Valid handlers: __http, https, ftp, torrent, tftp__.
+Boots a live image retrieved from __<url>__. Requires the dracut 'livenet'
+module. Valid handlers: __http, https, ftp, torrent, tftp__.
+
[listing]
-.Example
+.Examples
--
root=live:http://example.com/liveboot.img
root=live:ftp://ftp.example.com/liveboot.img
Enables debug output from the live boot process.
**rd.live.dir=**__<path>__::
-Specifies the directory within the squashfs where the ext3fs.img or rootfs.img
-can be found. By default, this is __LiveOS__.
+Specifies the directory within the boot device where the squashfs.img or
+rootfs.img can be found. By default, this is `/LiveOS`.
**rd.live.squashimg=**__<filename of SquashFS image>__::
Specifies the filename for a SquashFS image of the root filesystem.
**rd.live.ram=**1::
Copy the complete image to RAM and use this for booting. This is useful
-when the image resides on, i.e., a DVD which needs to be ejected later on.
+when the image resides on, e.g., a DVD which needs to be ejected later on.
-**rd.live.overlay=**__<devspec>__:__(<pathspec>|auto)__|__none__::
-Allow the usage of a permanent overlay.
-- _<devspec>_ specifies the path to a device with a mountable filesystem.
-- _<pathspec>_ is the path to a file within that filesystem, which shall be
+**rd.live.overlay={**__<devspec>__[:__{<pathspec>|auto}__]|__none__}::
+Manage the usage of a permanent overlay.
++
+--
+* _<devspec>_ specifies the path to a device with a mountable filesystem.
+* _<pathspec>_ is the path to a file within that filesystem, which shall be
used to persist the changes made to the device specified by the
**root=live:__<url>__** option.
-- _none_ specifies no overlay when an uncompressed live root filesystem is
-available.
++
+The default _pathspec_, when _auto_ or no _:<pathspec>_ is given, is
+`/<+++<b>rd.live.dir</b>+++>/overlay-<label>-<uuid>`, where _<label>_ is the
+device LABEL, and _<uuid>_ is the device UUID.
+* _none_ (the word itself) specifies that no overlay will be used, such as when
+an uncompressed, writable live root filesystem is available.
++
+If a persistent overlay __is detected__ at the standard LiveOS path, the
+overlay & overlay type detected, whether Device-mapper or OverlayFS, will be
+used.
+--
+
[listing]
-.Example
+.Examples
--
rd.live.overlay=/dev/sdb1:persistent-overlay.img
+rd.live.overlay=UUID=99440c1f-8daa-41bf-b965-b7240a8996f4
--
**rd.live.overlay.size=**__<size_MiB>__::
-Specifies a non-persistent overlay size in MiB. The default is _512_.
+Specifies a non-persistent Device-mapper overlay size in MiB. The default is
+_32768_.
**rd.live.overlay.readonly=**1::
-Specifies a non-persistent, writable snapshot overlay to be stacked over a
-read-only snapshot of the root filesystem, `/dev/mapper/live-ro`.
+This is used to boot with a normally read-write persistent overlay in a
+read-only mode. With this option, either an additional, non-persistent,
+writable snapshot overlay will be stacked over a read-only snapshot,
+`/dev/mapper/live‑ro`, of the base filesystem with the persistent overlay, or a
+read-only loop device, in the case of a writable __rootfs.img__, or an OverlayFS
+mount will use the persistent overlay directory linked at `/run/overlayfs‑r` as
+an additional lower layer along with the base root filesystem and apply a
+transient, writable upper directory overlay, in order to complete the booted
+root filesystem.
**rd.live.overlay.reset=**1::
-Specifies that a persistent overlay should be reset on boot. All root
+Specifies that a persistent overlay should be reset on boot. All previous root
filesystem changes are vacated by this action.
**rd.live.overlay.thin=**1::
that memory is given back to the kernel when the filesystem does not claim it
anymore.
+**rd.live.overlay.overlayfs=**1::
+Enables the use of the *OverlayFS* kernel module, if available, to provide a
+copy-on-write union directory for the root filesystem. OverlayFS overlays are
+directories of the files that have changed on the read-only base (lower)
+filesystem. The root filesystem is provided through a special overlay type
+mount that merges the lower and upper directories. If an OverlayFS upper
+directory is not present on the boot device, a tmpfs directory will be created
+at `/run/overlayfs` to provide temporary storage. Persistent storage can be
+provided on vfat or msdos formatted devices by supplying the OverlayFS upper
+directory within an embedded filesystem that supports the creation of trusted.*
+extended attributes and provides a valid d_type in readdir responses, such as
+with ext4 and xfs. On non-vfat-formatted devices, a persistent OverlayFS
+overlay can extend the available root filesystem storage up to the capacity of
+the LiveOS disk device.
++
+If a persistent overlay is detected at the standard LiveOS path, the overlay &
+overlay type detected, whether OverlayFS or Device-mapper, will be used.
++
+The **rd.live.overlay.readonly** option, which allows a persistent overlayfs to
+be mounted read-only through a higher level transient overlay directory, has
+been implemented through the multiple lower layers feature of OverlayFS.
+
+
+ZIPL
+~~~~
+**rd.zipl=**__<path to blockdevice>__::
+ Update the dracut commandline with the values found in the
+ _dracut-cmdline.conf_ file on the given device.
+ The values are merged into the existing commandline values
+ and the udev events are regenerated.
++
+[listing]
+.Example
+--
+rd.zipl=UUID=0fb28157-99e3-4395-adef-da3f7d44835a
+--
+
+CIO_IGNORE
+~~~~~~~~~~
+**rd.cio_accept=**__<device-ids>__::
+ Remove the devices listed in <device-ids> from the default
+ cio_ignore kernel command-line settings.
+ <device-ids> is a list of comma-separated CCW device ids.
+ The default for this value is taken from the
+ _/boot/zipl/active_devices.txt_ file.
++
+[listing]
+.Example
+--
+rd.cio_accept=0.0.0180,0.0.0800,0.0.0801,0.0.0802
+--
Plymouth Boot Splash
~~~~~~~~~~~~~~~~~~~~
rdbreak:: rd.break
-rd_CCW:: rd.ccw
+rd.ccw:: rd.znet
+rd_CCW:: rd.znet
rd_DASD_MOD:: rd.dasd
projects / thirdparty / dracut.git / blobdiff