INITRAMFS.CONF(5)         (2018/07/18)          INITRAMFS.CONF(5)

     NAME
          initramfs.conf - configuration file for mkinitramfs

     DESCRIPTION
          The behaviour of mkinitramfs can be modified by its configu-
          ration file.

          Each line in the file can be a configuration variable, a
          blank line, or a comment. The value of an variable is
          assigned by an statement of the form: name=[value]

          Configuration options can be broken out into configuration
          snippets and placed in individual files in the
          /etc/initramfs-tools/conf.d directory.  Files in this direc-
          tory are always read after the main configuration file, so
          you can override the settings in the main config file with-
          out editing it directly.

     GENERAL VARIABLES
           MODULES
               Specifies the modules for the initramfs image.

               Modules listed in /etc/initramfs-tools/modules and
               /usr/share/initramfs-tools/modules.d/* are always
               included in the initramfs, and are loaded early in the
               boot process.

               list doesn't load any additional modules at boot time,
               other than those listed in the above files.

               most adds most file system, all ata, sata, scsi and usb
               drivers.

               dep tries to guess which modules are necessary for the
               running box and only adds those modules.

               netboot adds the base and network modules, but skips
               block devices.

               The default setting is most.

           BUSYBOX
               Include busybox utilities for the boot scripts.  If set
               to 'n' mkinitramfs will build an initramfs without

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               busybox.  Beware that many boot scripts need busybox
               utilities.

           KEYMAP
               If set to 'y', the console keymap will be loaded during
               the initramfs stage.  The keymap will anyway be loaded
               by the initscripts later, and the packages that might
               need input will normally set this variable automati-
               cally, so there should normally be no need to set this.

           COMPRESS
               Specifies the compression method used for the initramfs
               image.  mkinitramfs will default to gzip if the kernel
               lacks support (CONFIG_RD) or the corresponding user-
               space utility is not present.

           UMASK
               Set the umask value of the generated initramfs file.
               Useful to not disclose eventual keys.

           BOOT
               Allows one to use an nfs drive as the root of the
               drive.  The default is to boot from local media (hard
               drive, USB stick).  Set to nfs for an NFS root share.

           RUNSIZE
               The size of the /run tmpfs mount point in bytes (suf-
               fixes are supported) or as percentage of your physical
               RAM. This parameter is used as the value of the size
               mount option to tmpfs. See
               https://www.kernel.org/doc/Documentation/filesystems/tmpfs.txt
               for details. Can be overridden by an optional
               initramfs.runsize= bootarg.  The default is 10%.

     VARIABLES FOR LOCAL BOOT
           RESUME
               Specifies the device used for suspend-to-disk (hiberna-
               tion), which the initramfs code should attempt to
               resume from.  If this is not defined or is set to auto,
               mkinitramfs will automatically select the largest
               available swap partition.  Set it to none to disable
               resume from disk.

           FSTYPE
               Specifies the filesystem type(s) to support, separated

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               by commas.  If this is not defined or is set to auto,
               mkinitramfs will automatically detect the current root
               and /usr filesystem types.

     VARIABLES FOR NFS BOOT
           DEVICE
               Specifies the default network interface to use, like
               eth0.  The ip or BOOTIF bootargs may override this.

           ROOT
               Allows optional root bootarg hardcoding, when no root
               bootarg can be passed.  A root bootarg overrides that
               special setting.

           NFSROOT
               Defaults to auto in order to pick up value from DHCP
               server.  Otherwise you need to specify HOST:MOUNT.

     FILES
          /etc/initramfs-tools/initramfs.conf

     AUTHOR
          The initramfs-tools are written by Maximilian Attems
          <maks@debian.org>, Jeff Bailey <jbailey@raspberryginger.com>
          and numerous others.  Loosely based on mkinitrd.conf by Her-
          bert Xu.

     SEE ALSO
           initramfs-tools(7), mkinitramfs(8), update-initramfs(8).

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