---
name: "initramfs.conf"
section: "5"
platform: "linux"
package: "initramfs-tools-core"
version: "0.148.4"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/initramfs.conf"
---

# initramfs.conf(5)

configuration file for mkinitramfs

## NAME

initramfs.conf - configuration file for mkinitramfs

## DESCRIPTION

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.

## 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 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.**

- **COMPRESSLEVEL**

  **Specifies the compression level used for the initramfs image.** **mkinitramfs** **will default to 9 for lz4, 9 for zstd, and the builtin defaults for all** **others.**

- **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%.

## VARIABLES FOR LOCAL BOOT

- **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.**

## 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 Herbert Xu.**

## SEE ALSO

[*initramfs-tools*(7)](/initramfs-tools/7.md), [*mkinitramfs*(8)](/mkinitramfs/8.md), [*update-initramfs*(8)](/update-initramfs/8.md).