dracut(category9-linux-distributionen.html) - phpMan

DRACUT(8)                           dracut                           DRACUT(8)

NAME
       dracut - low-level tool for generating an initramfs image
SYNOPSIS
       dracut [OPTION...] [<image> [<kernel version>]]
DESCRIPTION
       Create an initramfs <image> for the kernel with the version <kernel
       version>. If <kernel version> is omitted, then the version of the
       actual running kernel is used. If <image> is omitted or empty, then the
       default location /boot/initramfs-<kernel version>.img is used.
       dracut creates an initial image used by the kernel for preloading the
       block device modules (such as IDE, SCSI or RAID) which are needed to
       access the root filesystem, mounting the root filesystem and booting
       into the real system.
       At boot time, the kernel unpacks that archive into RAM disk, mounts and
       uses it as initial root file system. All finding of the root device
       happens in this early userspace.
       For a complete list of kernel command line options see
       dracut.cmdline(7).
       If you are dropped to an emergency shell, while booting your initramfs,
       the file /run/initramfs/rdsosreport.txt is created, which can be safed
       to a (to be mounted by hand) partition (usually /boot) or a USB stick.
       Additional debugging info can be produced by adding rd.debug to the
       kernel command line. /run/initramfs/rdsosreport.txt contains all logs
       and the output of some tools. It should be attached to any report about
       dracut problems.
USAGE
       To create a initramfs image, the most simple command is:
           # dracut
       This will generate a general purpose initramfs image, with all possible
       functionality resulting of the combination of the installed dracut
       modules and system tools. The image is /boot/initramfs-<kernel
       version>.img and contains the kernel modules of the currently active
       kernel with version <kernel version>.
       If the initramfs image already exists, dracut will display an error
       message, and to overwrite the existing image, you have to use the
       --force option.
           # dracut --force
       If you want to specify another filename for the resulting image you
       would issue a command like:
           # dracut foobar.img
       To generate an image for a specific kernel version, the command would
       be:
           # dracut foobar.img 2.6.40-1.rc5.f20
       A shortcut to generate the image at the default location for a specific
       kernel version is:
           # dracut --kver 2.6.40-1.rc5.f20
       If you want to create lighter, smaller initramfs images, you may want
       to specify the --hostonly or -H option. Using this option, the
       resulting image will contain only those dracut modules, kernel modules
       and filesystems, which are needed to boot this specific machine. This
       has the drawback, that you can't put the disk on another controller or
       machine, and that you can't switch to another root filesystem, without
       recreating the initramfs image.
           Note
           On RHEL-7 the hostonly mode is the default mode. Generic
           "non-hostonly" images are created, if the dracut-config-generic rpm
           is installed. The rescue kernel entry in the bootloader menu is
           also a generic image.
   Inspecting the Contents
       To see the contents of the image created by dracut, you can use the
       lsinitrd tool.
           # lsinitrd | less
       To display the contents of a file in the initramfs also use the
       lsinitrd tool:
           # lsinitrd -f /etc/ld.so.conf
           include ld.so.conf.d/*.conf
   Adding dracut Modules
       Some dracut modules are turned off by default and have to be activated
       manually. You can do this by adding the dracut modules to the
       configuration file /etc/dracut.conf or /etc/dracut.conf.d/myconf.conf.
       See dracut.conf(5). You can also add dracut modules on the command line
       by using the -a or --add option:
           # dracut --add bootchart initramfs-bootchart.img
       To see a list of available dracut modules, use the --list-modules
       option:
           # dracut --list-modules
   Omitting dracut Modules
       Sometimes you don't want a dracut module to be included for reasons of
       speed, size or functionality. To do this, either specify the
       omit_dracutmodules variable in the dracut.conf or
       /etc/dracut.conf.d/myconf.conf configuration file (see dracut.conf(5)),
       or use the -o or --omit option on the command line:
           # dracut -o "multipath lvm" no-multipath-lvm.img
   Adding Kernel Modules
       If you need a special kernel module in the initramfs, which is not
       automatically picked up by dracut, you have the use the --add-drivers
       option on the command line or the drivers vaiable in the
       /etc/dracut.conf or /etc/dracut.conf.d/myconf.conf configuration file
       (see dracut.conf(5)):
           # dracut --add-drivers mymod initramfs-with-mymod.img
   Boot parameters
       An initramfs generated without the "hostonly" mode, does not contain
       any system configuration files (except for some special exceptions), so
       the configuration has to be done on the kernel command line. With this
       flexibility, you can easily boot from a changed root partition, without
       the need to recompile the initramfs image. So, you could completly
       change your root partition (move it inside a md raid with encryption
       and LVM on top), as long as you specify the correct filesystem LABEL or
       UUID on the kernel command line for your root device, dracut will find
       it and boot from it.
       The kernel command line usually can be configured in
       /boot/grub2/grub.cfg (or /boot/efi/EFI/redhat/grub.cfg for EFI
       systems), if grub2 is your bootloader and it also can be edited in the
       real boot process in the grub menu.
       The kernel command line can also be provided by the dhcp server with
       the root-path option. See the section called "Network Boot".
       For a full reference of all kernel command line parameters, see
       dracut.cmdline(5).
       To get a quick start for the suitable kernel command line on your
       system, use the --print-cmdline option:
           # dracut --print-cmdline
            root=UUID=8b8b6f91-95c7-4da2-831b-171e12179081 rootflags=rw,relatime,discard,data=ordered rootfstype=ext4
       Specifying the root Device
           This is the only option dracut really needs to boot from your root
           partition. Because your root partition can live in various
           environments, there are a lot of formats for the root= option. The
           most basic one is root=<path to device node>:
               root=/dev/sda2
           Because device node names can change, dependent on the drive
           ordering, you are encouraged to use the filesystem identifier
           (UUID) or filesystem label (LABEL) to specify your root partition:
               root=UUID=19e9dda3-5a38-484d-a9b0-fa6b067d0331
           or
               root=LABEL=myrootpartitionlabel
           To see all UUIDs or LABELs on your system, do:
               # ls -l /dev/disk/by-uuid
           or
               # ls -l /dev/disk/by-label
           If your root partition is on the network see the section called
           "Network Boot".
       Keyboard Settings
           If you have to input passwords for encrypted disk volumes, you
           might want to set the keyboard layout and specify a display font.
           A typical german kernel command would contain:
               rd.vconsole.font=latarcyrheb-sun16 rd.vconsole.keymap=de-latin1-nodeadkeys rd.locale.LANG=de_DE.UTF-8
           Setting these options can override the setting stored on your
           system, if you use a modern init system, like systemd.
       Blacklisting Kernel Modules
           Sometimes it is required to prevent the automatic kernel module
           loading of a specific kernel module. To do this, just add
           rd.blacklist=<kernel module name>, with <kernel module name> not
           containing the .ko suffix, to the kernel command line. For example:
               rd.driver.blacklist=mptsas rd.driver.blacklist=nouveau
           The option can be specified multiple times on the kernel command
           line.
       Speeding up the Boot Process
           If you want to speed up the boot process, you can specify as much
           information for dracut on the kernel command as possible. For
           example, you can tell dracut, that you root partition is not on a
           LVM volume or not on a raid partition, or that it lives inside a
           specific crypto LUKS encrypted volume. By default, dracut searches
           everywhere. A typical dracut kernel command line for a plain
           primary or logical partition would contain:
               rd.luks=0 rd.lvm=0 rd.md=0 rd.dm=0
           This turns off every automatic assembly of LVM, MD raids, DM raids
           and crypto LUKS.
           Of course, you could also omit the dracut modules in the initramfs
           creation process, but then you would lose the posibility to turn it
           on on demand.
   Injecting custom Files
       To add your own files to the initramfs image, you have several
       possibilities.
       The --include option let you specify a source path and a target path.
       For example
           # dracut --include cmdline-preset /etc/cmdline.d/mycmdline.conf initramfs-cmdline-pre.img
       will create an initramfs image, where the file cmdline-preset will be
       copied inside the initramfs to /etc/cmdline.d/mycmdline.conf. --include
       can only be specified once.
           # mkdir -p rd.live.overlay/etc/cmdline.d
           # mkdir -p rd.live.overlay/etc/conf.d
           # echo "ip=dhcp" >> rd.live.overlay/etc/cmdline.d/mycmdline.conf
           # echo export FOO=testtest >> rd.live.overlay/etc/conf.d/testvar.conf
           # echo export BAR=testtest >> rd.live.overlay/etc/conf.d/testvar.conf
           # tree rd.live.overlay/
           rd.live.overlay/
           `-- etc
               |-- cmdline.d
               |   `-- mycmdline.conf
               `-- conf.d
                   `-- testvar.conf
           # dracut --include rd.live.overlay / initramfs-rd.live.overlay.img
       This will put the contents of the rd.live.overlay directory into the
       root of the initramfs image.
       The --install option let you specify several files, which will get
       installed in the initramfs image at the same location, as they are
       present on initramfs creation time.
           # dracut --install 'strace fsck.ext3 ssh' initramfs-dbg.img
       This will create an initramfs with the strace, fsck.ext3 and ssh
       executables, together with the libraries needed to start those. The
       --install option can be specified multiple times.
   Network Boot
       If your root partition is on a network drive, you have to have the
       network dracut modules installed to create a network aware initramfs
       image.
       On a Red Hat Enterprise Linux or Fedora system, this means, you have to
       install the dracut-network rpm package:
           # yum install dracut-network
       The resulting initramfs image can be served by a boot manager residing
       on your local hard drive or it can be served by a PXE/TFTP server.
       How to setup your PXE/TFTP server can be found in the Red Hat
       Enterprise Linux Storage Administration Guide[1].
       If you specify ip=dhcp on the kernel command line, then dracut asks a
       dhcp server about the ip adress for the machine. The dhcp server can
       also serve an additional root-path, which will set the root device for
       dracut. With this mechanism, you have static configuration on your
       client machine and a centralized boot configuration on your TFTP/DHCP
       server. If you can't pass a kernel command line, then you can inject
       /etc/cmdline.d/mycmdline.conf, with a method described in the section
       called "Injecting custom Files".
       Reducing the Image Size
           To reduce the size of the initramfs, you should create it with by
           ommitting all dracut modules, which you know, you don't need to
           boot the machine.
           You can also specify the exact dracut and kernel modules to produce
           a very tiny initramfs image.
           For example for a NFS image, you would do:
               # dracut -m "nfs network  base" initramfs-nfs-only.img
           Then you would boot from this image with your target machine and
           reduce the size once more by creating it on the target machine with
           the --host-only option:
               # dracut -m "nfs network base" --host-only initramfs-nfs-host-only.img
           This will reduce the size of the initramfs image significantly.
TROUBLESHOOTING
       If the boot process does not succeed, you have several options to debug
       the situation. Some of the basic operations are covered here. For more
       information you should also visit:
       http://fedoraproject.org/wiki/How_to_debug_Dracut_problems
   Identifying your problem area
        1. Remove 'rhgb' and 'quiet' from the kernel command line
        2. Add 'rd.shell' to the kernel command line. This will present a
           shell should dracut be unable to locate your root device
        3. Add 'rd.shell rd.debug log_buf_len=1M' to the kernel command line
           so that dracut shell commands are printed as they are executed
        4. The file /run/initramfs/rdsosreport.txt is generated, which
           contains all the logs and the output of all significant tools,
           which are mentioned later.
       If you want to save that output, simply mount /boot by hand or insert
       an USB stick and mount that. Then you can store the output for later
       inspection.
   Information to include in your report
       All bug reports
           In all cases, the following should be mentioned and attached to
           your bug report:
           o   The exact kernel command-line used. Typically from the
               bootloader configuration file (e.g.  /boot/grub2/grub.cfg (or
               /boot/efi/EFI/redhat/grub.cfg for EFI systems)) or from
               /proc/cmdline.
           o   A copy of your disk partition information from /etc/fstab,
               which might be obtained booting an old working initramfs or a
               rescue medium.
           o   Turn on dracut debugging (see the debugging dracut section),
               and attach the file /run/initramfs/rdsosreport.txt.
           o   If you use a dracut configuration file, please include
               /etc/dracut.conf and all files in /etc/dracut.conf.d/*.conf
       Network root device related problems
           This section details information to include when experiencing
           problems on a system whose root device is located on a network
           attached volume (e.g. iSCSI, NFS or NBD). As well as the
           information from the section called "All bug reports", include the
           following information:
           o   Please include the output of
                   # /sbin/ifup <interfacename>
                   # ip addr show
   Debugging dracut
       Configure a serial console
           Successfully debugging dracut will require some form of console
           logging during the system boot. This section documents configuring
           a serial console connection to record boot messages.
            1. In /boot/grub2/grub.cfg (or /boot/efi/EFI/redhat/grub.cfg for
               EFI systems), add the following boot arguments to the 'linux16'
               line:
                   console=tty0 console=ttyS0,9600
            2. More detailed information on how to configure the kernel for
               console output can be found at
               http://www.faqs.org/docs/Linux-HOWTO/Remote-Serial-Console-HOWTO.html#CONFIGURE-KERNEL.
       Using the dracut shell
           dracut offers a shell for interactive debugging in the event dracut
           fails to locate your root filesystem. To enable the shell:
            1. Add the boot parameter 'rd.shell' to your bootloader
               configuration file (e.g.  /boot/grub2/grub.cfg (or
               /boot/efi/EFI/redhat/grub.cfg for EFI systems))
            2. Remove the boot arguments 'rhgb' and 'quiet'
               A sample grub.cfg bootloader configuration file snippet is
               listed below.
                   menuentry 'Red Hat Enterprise Linux Server (3.10.0-308.el7.x86_64) 7.0 (Maipo)' [...] {
                     [...]
                     linux16 /vmlinuz-3.10.0-308.el7.x86_64 ro root=/dev/mapper/vg_uc1-lv_root console=tty0 rd.shell
                     initrd16 /initramfs-3.10.0-308.el7.x86_64.img
                     [...]
                   }
            3. If system boot fails, you will be dropped into a shell as seen
               in the example below.
                   No root device found
                   Dropping to debug shell.
                   #
            4. Use this shell prompt to gather the information requested above
               (see the section called "All bug reports").
       Accessing the root volume from the dracut shell
           From the dracut debug shell, you can manually perform the task of
           locating and preparing your root volume for boot. The required
           steps will depend on how your root volume is configured. Common
           scenarios include:
           o   A block device (e.g.  /dev/sda7)
           o   A LVM logical volume (e.g.  /dev/VolGroup00/LogVol00)
           o   An encrypted device (e.g.
               /dev/mapper/luks-4d5972ea-901c-4584-bd75-1da802417d83)
           o   A network attached device (e.g.
               netroot=iscsi:@192.168.0.4::3260::iqn.2009-02.org.example:for.all)
           The exact method for locating and preparing will vary. However, to
           continue with a successful boot, the objective is to locate your
           root volume and create a symlink /dev/root which points to the file
           system. For example, the following example demonstrates accessing
           and booting a root volume that is an encrypted LVM Logical volume.
            1. Inspect your partitions using parted
                   # parted /dev/sda -s p
                   Model: ATA HTS541060G9AT00 (scsi)
                   Disk /dev/sda: 60.0GB
                   Sector size (logical/physical): 512B/512B
                   Partition Table: msdos
                   Number  Start   End     Size    Type      File system  Flags
                   1      32.3kB  10.8GB  107MB   primary   ext4         boot
                   2      10.8GB  55.6GB  44.7GB  logical                lvm
            2. You recall that your root volume was a LVM logical volume. Scan
               and activate any logical volumes.
                   # lvm vgscan
                   # lvm vgchange -ay
            3. You should see any logical volumes now using the command blkid:
                   # blkid
                   /dev/sda1: UUID="3de247f3-5de4-4a44-afc5-1fe179750cf7" TYPE="ext4"
                   /dev/sda2: UUID="Ek4dQw-cOtq-5MJu-OGRF-xz5k-O2l8-wdDj0I" TYPE="LVM2_member"
                   /dev/mapper/linux-root: UUID="def0269e-424b-4752-acf3-1077bf96ad2c" TYPE="crypto_LUKS"
                   /dev/mapper/linux-home: UUID="c69127c1-f153-4ea2-b58e-4cbfa9257c5e" TYPE="ext3"
                   /dev/mapper/linux-swap: UUID="47b4d329-975c-4c08-b218-f9c9bf3635f1" TYPE="swap"
            4. From the output above, you recall that your root volume exists
               on an encrypted block device. Following the guidance disk
               encryption guidance from the Installation Guide, you unlock
               your encrypted root volume.
                   # UUID=$(cryptsetup luksUUID /dev/mapper/linux-root)
                   # cryptsetup luksOpen /dev/mapper/linux-root luks-$UUID
                   Enter passphrase for /dev/mapper/linux-root:
                   Key slot 0 unlocked.
            5. Next, make a symbolic link to the unlocked root volume
                   # ln -s /dev/mapper/luks-$UUID /dev/root
            6. With the root volume available, you may continue booting the
               system by exiting the dracut shell
                   # exit
       Additional dracut boot parameters
           For more debugging options, see dracut.cmdline(7).
       Debugging dracut on shutdown
           To debug the shutdown sequence on systemd systems, you can rd.break
           on pre-shutdown or shutdown.
           To do this from an already booted system:
               # mkdir -p /run/initramfs/etc/cmdline.d
               # echo "rd.break=pre-shutdown" > /run/initramfs/etc/cmdline.d/debug.conf
               # touch /run/initramfs/.need_shutdown
           This will give you a dracut shell after the system pivot'ed back in
           the initramfs.
OPTIONS
       --kver <kernel version>
           set the kernel version. This enables to specify the kernel version,
           without specifying the location of the initramfs image. For
           example:
           # dracut --kver 3.5.0-0.rc7.git1.2.fc18.x86_64
       -f, --force
           overwrite existing initramfs file.
       -m, --modules <list of dracut modules>
           specify a space-separated list of dracut modules to call when
           building the initramfs. Modules are located in
           /usr/lib/dracut/modules.d. This parameter can be specified multiple
           times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --modules "module1 module2"  ...
       -o, --omit <list of dracut modules>
           omit a space-separated list of dracut modules. This parameter can
           be specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --omit "module1 module2"  ...
       -a, --add <list of dracut modules>
           add a space-separated list of dracut modules to the default set of
           modules. This parameter can be specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --add "module1 module2"  ...
       --force-add <list of dracut modules>
           force to add a space-separated list of dracut modules to the
           default set of modules, when -H is specified. This parameter can be
           specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --force-add "module1 module2"  ...
       -d, --drivers <list of kernel modules>
           specify a space-separated list of kernel modules to exclusively
           include in the initramfs. The kernel modules have to be specified
           without the ".ko" suffix. This parameter can be specified multiple
           times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --drivers "kmodule1 kmodule2"  ...
       --add-drivers <list of kernel modules>
           specify a space-separated list of kernel modules to add to the
           initramfs. The kernel modules have to be specified without the
           ".ko" suffix. This parameter can be specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --add-drivers "kmodule1 kmodule2"  ...
       --force-drivers <list of kernel modules>
           See add-drivers above. But in this case it is ensured that the
           drivers are tried to be loaded early via modprobe.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --force-drivers "kmodule1 kmodule2"  ...
       --omit-drivers <list of kernel modules>
           specify a space-separated list of kernel modules not to add to the
           initramfs. The kernel modules have to be specified without the
           ".ko" suffix. This parameter can be specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --omit-drivers "kmodule1 kmodule2"  ...
       --filesystems <list of filesystems>
           specify a space-separated list of kernel filesystem modules to
           exclusively include in the generic initramfs. This parameter can be
           specified multiple times.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --filesystems "filesystem1 filesystem2"  ...
       -k, --kmoddir <kernel directory>
           specify the directory, where to look for kernel modules
       --fwdir <dir>[:<dir>...]++
           specify additional directories, where to look for firmwares. This
           parameter can be specified multiple times.
       --kernel-cmdline <parameters>
           specify default kernel command line parameters
       --kernel-only
           only install kernel drivers and firmware files
       --no-kernel
           do not install kernel drivers and firmware files
       --early-microcode
           Combine early microcode with ramdisk
       --no-early-microcode
           Do not combine early microcode with ramdisk
       --print-cmdline
           print the kernel command line for the current disk layout
       --mdadmconf
           include local /etc/mdadm.conf
       --nomdadmconf
           do not include local /etc/mdadm.conf
       --lvmconf
           include local /etc/lvm/lvm.conf
       --nolvmconf
           do not include local /etc/lvm/lvm.conf
       --fscks [LIST]
           add a space-separated list of fsck tools, in addition to
           dracut.conf's specification; the installation is opportunistic
           (non-existing tools are ignored)
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --fscks "fsck.foo barfsck"  ...
       --nofscks
           inhibit installation of any fsck tools
       --strip
           strip binaries in the initramfs (default)
       --nostrip
           do not strip binaries in the initramfs
       --prelink
           prelink binaries in the initramfs (default)
       --noprelink
           do not prelink binaries in the initramfs
       --hardlink
           hardlink files in the initramfs (default)
       --nohardlink
           do not hardlink files in the initramfs
       --prefix <dir>
           prefix initramfs files with the specified directory
       --noprefix
           do not prefix initramfs files (default)
       -h, --help
           display help text and exit.
       --debug
           output debug information of the build process
       -v, --verbose
           increase verbosity level (default is info(4))
       -q, --quiet
           decrease verbosity level (default is info(4))
       -c, --conf <dracut configuration file>
           specify configuration file to use.
           Default: /etc/dracut.conf
       --confdir <configuration directory>
           specify configuration directory to use.
           Default: /etc/dracut.conf.d
       --tmpdir <temporary directory>
           specify temporary directory to use.
           Default: /var/tmp
       --sshkey <sshkey file>
           ssh key file used with ssh-client module.
       --logfile <logfile>
           logfile to use; overrides any setting from the configuration files.
           Default: /var/log/dracut.log
       -l, --local
           activates the local mode. dracut will use modules from the current
           working directory instead of the system-wide installed modules in
           /usr/lib/dracut/modules.d. This is useful when running dracut from
           a git checkout.
       -H, --hostonly
           Host-Only mode: Install only what is needed for booting the local
           host instead of a generic host and generate host-specific
           configuration.
               Warning
               If chrooted to another root other than the real root device,
               use "--fstab" and provide a valid /etc/fstab.
       -N, --no-hostonly
           Disable Host-Only mode
       --hostonly-cmdline: Store kernel command line arguments needed in the
       initramfs
       --no-hostonly-cmdline: Do not store kernel command line arguments
       needed in the initramfs
       --no-hostonly-default-device: Do not generate implicit host devices
       like root, swap, fstab, etc. Use "--mount" or "--add-device" to
       explicitly add devices as needed.
       --hostonly-i18n: Install only needed keyboard and font files according
       to the host configuration (default).
       --no-hostonly-i18n: Install all keyboard and font files available.
       --persistent-policy <policy>
           Use <policy> to address disks and partitions.  <policy> can be any
           directory name found in /dev/disk. E.g. "by-uuid", "by-label"
       --fstab
           Use /etc/fstab instead of /proc/self/mountinfo.
       --add-fstab <filename>
           Add entries of <filename> to the initramfs /etc/fstab.
       --mount "<device> <mountpoint> <filesystem type> [<filesystem options>
       [<dump frequency> [<fsck order>]]]"
           Mount <device> on <mountpoint> with <filesystem type> in the
           initramfs.  <filesystem options>, <dump options> and <fsck order>
           can be specified, see fstab manpage for the details. The default
           <filesystem options> is "defaults". The default <dump frequency> is
           "0". the default <fsck order> is "2".
       --add-device <device>
           Bring up <device> in initramfs, <device> should be the device name.
           This can be useful in hostonly mode for resume support when your
           swap is on LVM or an encrypted partition. [NB --device can be used
           for compatibility with earlier releases]
       -i, --include <SOURCE> <TARGET>
           include the files in the SOURCE directory into the TARGET directory
           in the final initramfs. If SOURCE is a file, it will be installed
           to TARGET in the final initramfs. This parameter can be specified
           multiple times.
       -I, --install <file list>
           install the space separated list of files into the initramfs.
               Note
               If [LIST] has multiple arguments, then you have to put these in
               quotes. For example:
                   # dracut --install "/bin/foo /sbin/bar"  ...
       --install-optional <file list>
           install the space separated list of files into the initramfs, if
           they exist.
       --gzip
           Compress the generated initramfs using gzip. This will be done by
           default, unless another compression option or --no-compress is
           passed. Equivalent to "--compress=gzip -9"
       --bzip2
           Compress the generated initramfs using bzip2.
               Warning
               Make sure your kernel has bzip2 decompression support compiled
               in, otherwise you will not be able to boot. Equivalent to
               "--compress=bzip2"
       --lzma
           Compress the generated initramfs using lzma.
               Warning
               Make sure your kernel has lzma decompression support compiled
               in, otherwise you will not be able to boot. Equivalent to "lzma
               --compress=lzma -9"
       --xz
           Compress the generated initramfs using xz.
               Warning
               Make sure your kernel has xz decompression support compiled in,
               otherwise you will not be able to boot. Equivalent to "lzma
               --compress=xz --check=crc32 --lzma2=dict=1MiB"
       --lzo
           Compress the generated initramfs using lzop.
           Warning
           Make sure your kernel has lzo decompression support compiled in,
           otherwise you will not be able to boot.
       --lz4
           Compress the generated initramfs using lz4.
           Warning
           Make sure your kernel has lz4 decompression support compiled in,
           otherwise you will not be able to boot.
       --compress <compressor>
           Compress the generated initramfs using the passed compression
           program. If you pass it just the name of a compression program, it
           will call that program with known-working arguments. If you pass a
           quoted string with arguments, it will be called with exactly those
           arguments. Depending on what you pass, this may result in an
           initramfs that the kernel cannot decompress.
       --no-compress
           Do not compress the generated initramfs. This will override any
           other compression options.
       --list-modules
           List all available dracut modules.
       -M, --show-modules
           Print included module's name to standard output during build.
       --keep
           Keep the initramfs temporary directory for debugging purposes.
       --printsize
           Print out the module install size
       --profile: Output profile information of the build process
       --ro-mnt: Mount / and /usr read-only by default.
       -L, --stdlog <level>
           [0-6] Specify logging level (to standard error)
                     0 - suppress any messages
                     1 - only fatal errors
                     2 - all errors
                     3 - warnings
                     4 - info
                     5 - debug info (here starts lots of output)
                     6 - trace info (and even more)
       --regenerate-all
           Regenerate all initramfs images at the default location with the
           kernel versions found on the system. Additional parameters are
           passed through.
FILES
       /var/log/dracut.log
           logfile of initramfs image creation
       /tmp/dracut.log
           logfile of initramfs image creation, if /var/log/dracut.log is not
           writable
       /etc/dracut.conf
           see dracut.conf5
       /etc/dracut.conf.d/*.conf
           see dracut.conf5
       /usr/lib/dracut/dracut.conf.d/*.conf
           see dracut.conf5
   Configuration in the initramfs
       /etc/conf.d/
           Any files found in /etc/conf.d/ will be sourced in the initramfs to
           set initial values. Command line options will override these values
           set in the configuration files.
       /etc/cmdline
           Can contain additional command line options. Deprecated, better use
           /etc/cmdline.d/*.conf.
       /etc/cmdline.d/*.conf
           Can contain additional command line options.
AVAILABILITY
       The dracut command is part of the dracut package and is available from
       https://dracut.wiki.kernel.org
AUTHORS
       Harald Hoyer
       Victor Lowther
       Philippe Seewer
       Warren Togami
       Amadeusz olnowski
       Jeremy Katz
       David Dillow
       Will Woods
SEE ALSO
       dracut.cmdline(7) dracut.conf(5)
NOTES
        1. Red Hat Enterprise Linux Storage Administration Guide
           http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/

dracut                            09/30/2020                         DRACUT(8)