systemd/man/bootctl.xml

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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<refentry id="bootctl" conditional='ENABLE_EFI'
    xmlns:xi="http://www.w3.org/2001/XInclude">
  <refentryinfo>
    <title>bootctl</title>
    <productname>systemd</productname>
  </refentryinfo>

  <refmeta>
    <refentrytitle>bootctl</refentrytitle>
    <manvolnum>1</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>bootctl</refname>
    <refpurpose>Control EFI firmware boot settings and manage boot loader</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>bootctl</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="req">COMMAND</arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>bootctl</command> can check the EFI firmware and boot loader status, list and manage
    available boot loaders and boot loader entries, and install, update, or remove the
    <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> boot
    loader on the current system.</para>
  </refsect1>

  <refsect1>
    <title>Generic EFI Firmware/Boot Loader Commands</title>

    <para>These commands are available on any EFI system, regardless of the boot loader used.</para>

    <variablelist>
      <varlistentry>
        <term><option>status</option></term>

        <listitem><para>Shows brief information about the system firmware, the boot loader that was used to boot the
        system, the boot loaders currently available in the ESP, the boot loaders listed in the firmware's list of boot
        loaders and the current default boot loader entry. If no command is specified, this is the implied
        default.</para></listitem>
      </varlistentry>
    </variablelist>

    <varlistentry>
      <term><option>reboot-to-firmware</option> <optional><replaceable>BOOL</replaceable></optional></term>

      <listitem><para>Query or set the "Reboot-Into-Firmware-Setup" flag of the EFI firmware. Takes a
      boolean argument which controls whether to show the firmware setup on next system reboot. If the
      argument is omitted shows the current status of the flag, or whether the flag is supported. This
      controls the same flag as <command>systemctl reboot --firmware-setup</command>, but is more
      low-level and allows setting the flag independently from actually requesting a
      reboot.</para></listitem>
    </varlistentry>

    <varlistentry>
      <term><option>systemd-efi-options</option> <optional><replaceable>STRING</replaceable></optional></term>

      <listitem><para>When called without the optional argument, prints the current value of the
      <literal>SystemdOptions</literal> EFI variable. When called with an argument, sets the
      variable to that value. See
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
      for the meaning of that variable.</para></listitem>
    </varlistentry>
  </refsect1>

  <refsect1>
    <title>Boot Loader Specification Commands</title>

    <para>These commands are available for all boot loaders that implement the <ulink
    url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink> and/or the <ulink
    url="https://systemd.io/BOOT_LOADER_INTERFACE">Boot Loader Interface</ulink>, such as
    <command>systemd-boot</command>.</para>

    <variablelist>

      <varlistentry>
        <term><option>list</option></term>

        <listitem><para>Shows all available boot loader entries implementing the <ulink
        url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink>, as well as any
        other entries discovered or automatically generated by a boot loader implementing the <ulink
        url="https://systemd.io/BOOT_LOADER_INTERFACE">Boot Loader
        Interface</ulink>.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>set-default</option> <replaceable>ID</replaceable></term>
        <term><option>set-oneshot</option> <replaceable>ID</replaceable></term>

        <listitem><para>Sets the default boot loader entry. Takes a single boot loader entry ID string as
        argument. The <option>set-oneshot</option> command will set the default entry only for the next boot,
        the <option>set-default</option> will set it persistently for all future boots.</para></listitem>

        <listitem><para>Optionally, the boot loader entry ID may be specified as one of: <option>@default</option>,
        <option>@oneshot</option> or <option>@current</option>, which correspond to the current default boot loader
        entry for all future boots, the current default boot loader entry for the next boot, and the currently booted
        boot loader entry. These special IDs are resolved to the current values of the EFI variables
        <varname>LoaderEntryDefault</varname>, <varname>LoaderEntryOneShot</varname> and <varname>LoaderEntrySelected</varname>,
        see <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink> for details.
        These special IDs are primarily useful as a quick way to persistently make the currently booted boot loader
        entry the default choice, or to upgrade the default boot loader entry for the next boot to the default boot
        loader entry for all future boots, but may be used for other operations too.
        When an empty string ("") is specified as an ID, then the corresponding EFI variable will be unset.
        </para></listitem>
      </varlistentry>

    </variablelist>
  </refsect1>

  <refsect1>
    <title><command>systemd-boot</command> Commands</title>

    <para>These commands manage the <command>systemd-boot</command> EFI boot loader, and do not work in
    conjunction with other boot loaders.</para>

    <variablelist>
      <varlistentry>
        <term><option>install</option></term>

        <listitem><para>Installs <command>systemd-boot</command> into the EFI system partition. A copy of
        <command>systemd-boot</command> will be stored as the EFI default/fallback loader at
        <filename><replaceable>ESP</replaceable>/EFI/BOOT/BOOT*.EFI</filename>. The boot loader is then added
        to the top of the firmware's boot loader list.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>update</option></term>

        <listitem><para>Updates all installed versions of
        <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>, if the
        available version is newer than the version installed in the EFI system partition. This also includes the EFI
        default/fallback loader at <filename><replaceable>ESP</replaceable>/EFI/BOOT/BOOT*.EFI</filename>. The boot
        loader is then added to end of the firmware's boot loader list if missing.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>remove</option></term>

        <listitem><para>Removes all installed versions of <command>systemd-boot</command> from the EFI system partition
        and the firmware's boot loader list.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>is-installed</option></term>

        <listitem><para>Checks whether <command>systemd-boot</command> is installed in the ESP. Note that a
        single ESP might host multiple boot loaders; this hence checks whether
        <command>systemd-boot</command> is one (of possibly many) installed boot loaders — and neither
        whether it is the default nor whether it is registered in any EFI variables.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>random-seed</option></term>

        <listitem><para>Generates a random seed and stores it in the EFI System Partition, for use by the
        <command>systemd-boot</command> boot loader. Also, generates a random 'system token' and stores it
        persistently as an EFI variable, if one has not been set before. If the boot loader finds the random
        seed in the ESP and the system token in the EFI variable it will derive a random seed to pass to the
        OS and a new seed to store in the ESP from the combination of both. The random seed passed to the OS
        is credited to the kernel's entropy pool by the system manager during early boot, and permits
        userspace to boot up with an entropy pool fully initialized very early on. Also see
        <citerefentry><refentrytitle>systemd-boot-system-token.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

        <para>See <ulink url="https://systemd.io/RANDOM_SEEDS">Random Seeds</ulink> for further
        information.</para></listitem>
      </varlistentry>

    </variablelist>
  </refsect1>

  <refsect1>
    <title>Options</title>
    <para>The following options are understood:</para>

    <variablelist>
      <varlistentry>
        <term><option>--esp-path=</option></term>
        <listitem><para>Path to the EFI System Partition (ESP). If not specified, <filename>/efi/</filename>,
        <filename>/boot/</filename>, and <filename>/boot/efi/</filename> are checked in turn.  It is
        recommended to mount the ESP to <filename>/efi/</filename>, if possible.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--boot-path=</option></term>
        <listitem><para>Path to the Extended Boot Loader partition, as defined in the <ulink
        url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink>. If not
        specified, <filename>/boot/</filename> is checked.  It is recommended to mount the Extended Boot
        Loader partition to <filename>/boot/</filename>, if possible.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-p</option></term>
        <term><option>--print-esp-path</option></term>
        <listitem><para>This option modifies the behaviour of <command>status</command>. Only prints the path
        to the EFI System Partition (ESP) to standard output and exits.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-x</option></term>
        <term><option>--print-boot-path</option></term>
        <listitem><para>This option modifies the behaviour of <command>status</command>. Only prints the path
        to the Extended Boot Loader partition if it exists, and the path to the ESP otherwise to standard
        output and exit. This command is useful to determine where to place boot loader entries, as they are
        preferably placed in the Extended Boot Loader partition if it exists and in the ESP otherwise.</para>

        <para>Boot Loader Specification Type #1 entries should generally be placed in the directory
        <literal>$(bootctl -x)/loader/entries/</literal>. Existence of that directory may also be used as
        indication that boot loader entry support is available on the system. Similarly, Boot Loader
        Specification Type #2 entries should be placed in the directory <literal>$(bootctl
        -x)/EFI/Linux/</literal>.</para>

        <para>Note that this option (similar to the <option>--print-booth-path</option> option mentioned
        above), is available independently from the boot loader used, i.e. also without
        <command>systemd-boot</command> being installed.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--no-variables</option></term>
        <listitem><para>Do not touch the firmware's boot loader list stored in EFI variables.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--graceful</option></term>
        <listitem><para>Ignore failure when the EFI System Partition cannot be found, or when EFI variables
        cannot be written. Currently only applies to random seed operations.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--make-machine-id-directory=yes|no|auto</option></term>
        <listitem><para>Control creation and deletion of the top-level machine ID directory on the file
        system containing boot loader entries (i.e. beneath the file system returned by
        <option>--print-boot-path</option> above) during <option>install</option> and
        <option>remove</option>, respectively.  <literal>auto</literal> is equivalent to
        <literal>yes</literal> if <filename>/etc/machine-id</filename> resides on a filesystem other than
        tmpfs and <literal>no</literal> otherwise (in the latter case the machine ID is likely transient and
        hence should not be used persistently in the ESP). Defaults to <literal>auto</literal>. See
        <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
        details about the machine ID concept and file.</para>

        <para>Overriding this may be desirable to hide the machine ID from the (unencrypted) ESP, configure a
        <citerefentry><refentrytitle>kernel-install</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        script, or, conversely, commit a transient machine ID.</para>

        <para>The top-level machine ID directory is useful to allow smooth multi-boot installations: each
        installed OS instance will have a different machine ID and thus a separate directory to place its
        boot-time resources in. If this feature is turned off with this option, care needs to be taken that
        multiple OS instances do not place conflicting files on the shared ESP and Extended Boot Loader
        Partitions, or that multiple OS instances are not possible.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="no-pager"/>
      <xi:include href="standard-options.xml" xpointer="help"/>
      <xi:include href="standard-options.xml" xpointer="version"/>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Exit status</title>
    <para>On success, 0 is returned, a non-zero failure code otherwise.</para>
  </refsect1>

  <refsect1>
    <title>Environment</title>
    <para>If <varname>$SYSTEMD_RELAX_ESP_CHECKS=1</varname> is set the validation checks for the ESP are
    relaxed, and the path specified with <option>--esp-path=</option> may refer to any kind of file system on
    any kind of partition.</para>

    <para>Similarly, <varname>$SYSTEMD_RELAX_XBOOTLDR_CHECKS=1</varname> turns off some validation checks for
    the Extended Boot Loader partition.</para>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
      <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink>,
      <ulink url="https://systemd.io/BOOT_LOADER_INTERFACE">Boot Loader Interface</ulink>,
      <citerefentry><refentrytitle>systemd-boot-system-token.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    </para>
  </refsect1>
</refentry>