focal (5) initramfs.conf.5.gz

Provided by: initramfs-tools-core_0.136ubuntu6.7_all bug

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.

        COMPCACHE_SIZE
              Amount of RAM to use for RAM-based compressed swap space.  The default is not to use compcache.

              An empty value - compcache isn't used, or added to the initramfs at all.

              An integer and K (e.g. 65536 K) - use a number of kilobytes.

              An integer and M (e.g. 256 M) - use a number of megabytes.

              An integer and G (e.g. 1 G) - use a number of gigabytes.

              An integer and % (e.g. 50 %) - use a percentage of the amount of RAM.

              You can optionally install the compcache package to configure this setting via  debconf  and  have
              userspace scripts to load and unload compcache.

        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%.

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.

VARIABLES FOR NFS BOOT

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

        VLAN  Specifies the VLAN tag id to setup, e.g. VLAN=eth0.1:eth0.  The vlan bootarg 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), mkinitramfs(8), update-initramfs(8).