initramfs.conf - configuration file for mkinitramfs
The behaviour of mkinitramfs can be modified by its
configuration 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 directory are always read after the main
configuration file, so you can override the settings in the main config file
without editing it directly.
- 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 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
automatically, 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 userspace 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 (suffixes 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%.
- RESUME
- Specifies the device used for suspend-to-disk (hibernation), 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 by commas. If this
is not defined or is set to auto, mkinitramfs will
automatically detect the current root and /usr filesystem types.
- 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.
- /etc/initramfs-tools/initramfs.conf
-
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 Herbert Xu.