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       mkinitramfs - low-level tool for generating an initramfs image


       mkinitramfs  [-c  compress] [-d confdir] [-k] -o outfile [-r root] [-v]

       mkinitramfs [--supported-host-version= hversion]

       mkinitramfs [--supported-target-version= tversion]


       The mkinitramfs script generates an initramfs image.  The initramfs  is
       a  compressed  cpio archive. The archive can be used on a different box
       of the same arch with the corresponding Linux kernel.   mkinitramfs  is
       meant  for  advanced  usage.  On  your local box update-initramfs calls
       mkinitramfs  with  the  relevant  parameters.   update-initramfs  keeps
       sha1sum  of  generated initramfs. It takes care to generate backups and
       eventually runs the bootloader.

       At boot time, the kernel unpacks that archive into RAM disk, mounts and
       uses  it  as  initial  root file system. All finding of the root device
       happens in this early userspace.


        -c  compress
              Override the COMPRESS setting in initramfs.conf.

        -d  confdir
              Set an alternate configuration directory.

        -k    Keep the temporary directory used to make the image.

        -o  outfile
              Write the image to outfile.

        -r  root
              Override the ROOT setting in initramfs.conf.

        -v    Set the verbose mode output.

              Set the kernel version of the initramfs image (defaults  to  the
              running kernel).

              This  option  queries  if  mkinitramfs  can create ramdisks on a
              running kernel of version hversion.

              This option queries  if  mkinitramfs  can  create  ramdisks  for
              kernel version tversion.


       mkinitramfs  honours  the  TMPDIR environment variable. If set, it uses
       subdirectories in the given directory to create its  temporary  working
       directories.  Else  it uses /tmp as default value for that purpose. The
       given directory should be on a filesystem which allows the execution of
       files  stored  there, i.e.  should not be mounted with the noexec mount


              The   default   configuration   file   for   the   script.   See
              initramfs.conf(5)   for   a   description   of   the   available
              configuration parameter.

              Specified modules will be put in the generated image and  loaded
              when  the system boots. The format - one per line - is identical
              to that of /etc/modules, which is described in modules(5).

              The conf.d directory allows to hardcode  bootargs  at  initramfs
              build  time  via  config  snippets.  This  allows to set ROOT or
              RESUME.  This is especially useful for bootloaders, which do not
              pass an root bootarg.

              If  this  file exists, it will be appended to the initramfs in a
              way that causes it to be loaded by ACPI.


       Create an initramfs for current running kernel:

       mkinitramfs -o ~/tmp/initramfs-$(uname -r)

       Create an initramfs for specific kernel and keep builddirs:

       mkinitramfs -k -o ~/tmp/initramfs-2.6.21-686 2.6.21-686

       Debug initramfs creation (check out written logfile)

       sh -x mkinitramfs -o ~/tmp/initramfs-$(uname -r) 2> ~/tmp/log


       The initramfs-tools are written by Maximilian Attems <>,
       Jeff Bailey <> and numerous others.


        initramfs.conf(5), initramfs-tools(8), update-initramfs(8).