<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<!--
This file is part of systemd.

Copyright 2013 Harald Hoyer

systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.

systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->

<refentry id="kernel-install">

  <refentryinfo>
    <title>kernel-install</title>
    <productname>systemd</productname>

    <authorgroup>
      <author>
        <contrib>Developer</contrib>
        <firstname>Harald</firstname>
        <surname>Hoyer</surname>
        <email>harald@redhat.com</email>
      </author>
    </authorgroup>
  </refentryinfo>

  <refmeta>
    <refentrytitle>kernel-install</refentrytitle>
    <manvolnum>8</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>kernel-install</refname>
    <refpurpose>Add and remove kernel and initramfs images to and from /boot</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>kernel-install</command> <arg choice="req">COMMAND</arg> <arg choice="req">KERNEL VERSION</arg> <arg choice="req">KERNEL IMAGE</arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>
    <para>
      <command>kernel-install</command> is used to install and remove kernel and
      initramfs images to and from <filename>/boot</filename>.
    </para>

    <para>kernel-install will execute the files located in the directory <filename>/usr/lib/kernel/install.d/</filename>
    and the local administration directory <filename>/etc/kernel/install.d/</filename>.
    All files are collectively sorted and executed in lexical order, regardless of the directories in
    which they live. However, files with identical file names replace each other.
    Files in <filename>/etc/kernel/install.d/</filename> take precedence over files with the same name
    in <filename>/usr/lib/kernel/install.d/</filename>. This can be used to override a system-supplied
    executables with a local file if needed; a symbolic link in <filename>/etc/kernel/install.d/</filename>
    with the same name as an executable in <filename>/usr/lib/kernel/install.d/</filename>,
    pointing to /dev/null, disables the executable entirely. Executables must have the
    extension .install; other extensions are ignored.</para>

  </refsect1>

  <refsect1>
    <title>Commands</title>
    <para>The following commands are understood:</para>
    <variablelist>
      <varlistentry>
        <term>add &lt;KERNEL VERSION> &lt;KERNEL IMAGE></term>
        <listitem>
          <para>calls every executable <filename>/usr/lib/kernel/install.d/*.install</filename>
          and <filename>/etc/kernel/install.d/*.install</filename> with the arguments
          "add &lt;KERNEL VERSION> <filename>/boot/&lt;MACHINE-ID>/&lt;KERNEL VERSION>/</filename>"</para>

          <para>kernel-install copies &lt;KERNEL IMAGE> to
          <filename>/boot/&lt;MACHINE-ID>/&lt;KERNEL VERSION>/linux</filename>.</para>

          <para>kernel-install also creates a boot loader entry according to the boot loader specification
          in <filename>/boot/loader/entries/&lt;OS-ID>-&lt;KERNEL VERSION>-&lt;MACHINE-ID>.conf</filename>.
          If the file <filename>initrd</filename> is found next to the <filename>linux</filename> file,
          the initrd will be added to the configuration.</para>
        </listitem>
      </varlistentry>
      <varlistentry>
        <term>remove &lt;KERNEL VERSION> &lt;KERNEL IMAGE></term>
        <listitem><para>calls every executable <filename>/usr/lib/kernel/install.d/*.install</filename>
        and <filename>/etc/kernel/install.d/*.install</filename> with the arguments:
        "remove &lt;KERNEL VERSION> <filename>/boot/&lt;MACHINE-ID>/&lt;KERNEL VERSION>/</filename>"
        </para>
        <para>kernel-install removes the entire directory <filename>/boot/&lt;MACHINE-ID>/&lt;KERNEL VERSION>/</filename>
        and the file <filename>/boot/loader/entries/&lt;OS-ID>-&lt;KERNEL VERSION>-&lt;MACHINE-ID>.conf</filename></para>
        </listitem>
      </varlistentry>

    </variablelist>

  </refsect1>

  <refsect1>
    <title>Exit status</title>
    <para>If every executable returns with 0, 0 is returned, a non-zero failure code otherwise.</para>
  </refsect1>

  <refsect1>
    <title>Files</title>
    <variablelist>
      <varlistentry>
        <term>
          <filename>/usr/lib/kernel/install.d/*.install</filename>
          <filename>/etc/kernel/install.d/*.install</filename>
        </term>
          <listitem>
            <para>Drop-in files, which are executed by kernel-install.</para>
          </listitem>
      </varlistentry>
      <varlistentry>
        <term>
          <filename>/etc/kernel/cmdline</filename>
          <filename>/proc/cmdline</filename>
        </term>
          <listitem>
            <para>The contents of the file <filename>/etc/kernel/cmdline</filename> specifies the kernel command line to use.
            If that file does not exist, <filename>/proc/cmdline</filename> is used.</para>
          </listitem>
      </varlistentry>
      <varlistentry>
        <term>
          <filename>/etc/machine-id</filename>
        </term>
          <listitem>
            <para>The contents of the file specifies the machine identifaction &lt;MACHINE-ID>.</para>
          </listitem>
      </varlistentry>
      <varlistentry>
        <term>
          <filename>/etc/os-release</filename>
        </term>
          <listitem>
            <para>The contents of the file specifies the the operating system id &lt;OS-ID>.</para>
          </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
      <ulink url="http://www.freedesktop.org/wiki/Specifications/BootLoaderSpec">Boot loader specification</ulink>
    </para>
  </refsect1>

</refentry>