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.
DEVICE
Specifies the network interface, like eth0.
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 <[email protected]>, Jeff Bailey <[email protected]> and numerous others. Loosely based on mkinitrd.conf by Herbert Xu.