File: systemd-gpt-auto-generator.xml

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<?xml version="1.0"?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
  "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->

<refentry id="systemd-gpt-auto-generator" conditional='HAVE_BLKID'
          xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-gpt-auto-generator</title>
    <productname>systemd</productname>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-gpt-auto-generator</refentrytitle>
    <manvolnum>8</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-gpt-auto-generator</refname>
    <refpurpose>Generator for automatically discovering and mounting root, <filename>/home/</filename>,
    <filename>/srv/</filename>, <filename>/var/</filename> and <filename>/var/tmp/</filename> partitions, as
    well as discovering and enabling swap partitions, based on GPT partition type GUIDs</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <para><filename>/usr/lib/systemd/system-generators/systemd-gpt-auto-generator</filename></para>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><filename>systemd-gpt-auto-generator</filename> is a unit generator that automatically discovers
    the root partition, <filename>/home/</filename>, <filename>/srv/</filename>, <filename>/var/</filename>,
    <filename>/var/tmp/</filename>, the EFI System Partition (ESP), the Extended Boot Loader Partition
    (XBOOTLDR), and swap partitions and creates mount and swap units for them, based on the partition type
    GUIDs of GUID partition tables (GPT). See <ulink url="https://uefi.org/specifications">UEFI
    Specification</ulink>, chapter 5 for more details. It implements the <ulink
    url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">UAPI.2 Discoverable
    Partitions Specification</ulink>.</para>

    <para>Note that this generator has no effect on non-GPT systems. It will also not create mount point
    configuration for directories which already contain files or if the mount point is explicitly configured
    in <citerefentry
    project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Additionally
    no unit will be created for the ESP or the XBOOTLDR partition if mount entries are found in the
    <filename>/boot/</filename> or <filename>/efi/</filename> hierarchies in <citerefentry
    project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>

    <para>If the units this generator creates are overridden, for example by units in directories with higher
    precedence, drop-ins and additional dependencies created by this generator might still be used.</para>

    <para>When run in the initial RAM disk (initrd) this generator can automatically search for the root file
    system. Specifically:

    <itemizedlist>
      <listitem><para>It will look for the root partition on the same physical disk where the EFI System
      Partition (ESP) is located. Note that support from the boot loader is required for this to work: the
      EFI variable <varname>LoaderDevicePartUUID</varname> of the
      <constant>4a67b082-0a4c-41cf-b6c7-440b29bb8c4f</constant> vendor UUID is used to determine from which
      partition (and hence disk) the system was booted. If the boot loader does not set this variable, this
      generator will not be able to detect the root partition. See the <ulink
      url="https://systemd.io/BOOT_LOADER_INTERFACE">Boot Loader Interface</ulink> for
      details.</para></listitem>

      <listitem><para>Alternatively, it will look for the root file system on a loopback block device whose
      <literal>.lo_name</literal> field is set to one of the literal strings <literal>rootdisk</literal> or
      <literal>rootdisk.raw</literal>. This field can be set via <command>losetup</command>'s
      <option>--loop-ref=</option> string. For images downloaded via
      <citerefentry><refentrytitle>systemd-import-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
      make sure to set the <literal>blockdev</literal> option and set the local name string to
      <literal>rootdisk</literal> to achieve this effect. Note that discovery of the root file system on
      loopback block devices like this is only done if <literal>root=gpt-auto</literal> or
      <literal>root=dissect</literal> is specified explicitly on the kernel command line, unlike the
      discovery based on the boot loader reported ESP which is also enabled if no <literal>root=</literal>
      parameter is specified at all. (The latter relies on <command>systemd-udevd.service</command>'s
      <filename>/dev/gpt-auto-root</filename> block device symlink generation).</para></listitem>
    </itemizedlist>
    </para>

    <para>When run on the host system (i.e. after successfully transitioning out of the initrd into the root
    filesystem) this generator will look for all other partitions on the same physical disk as the root
    partition. For this discovery, boot loader support is not required. Moreover, it is not required that the
    root partition was automatically discovered by the initrd (as described above) for the discovery of the
    non-root file partitions to take place. Or in other words: automatic discovery of the root file system
    and of the non-root file systems are independent operations, that do not rely on each other, and are done
    during two distinct phases of the boot process (one in the initrd, the other after). These partitions will
    not be searched for on systems where the root file system is distributed on multiple disks, for example
    via btrfs RAID.</para>

    <para>The root partition can be configured explicitly by symlinking
    <filename>/run/systemd/volatile-root</filename> to <filename>/dev/block/$major:$minor</filename>. This is
    especially useful if the root mount has been replaced by some form of volatile file system
    (overlayfs).</para>

    <para><filename>systemd-gpt-auto-generator</filename> is useful for centralizing file system
    configuration in the partition table and making configuration in <filename>/etc/fstab</filename> or on
    the kernel command line unnecessary.</para>

    <para>This generator looks for the partitions based on their
    partition type GUID. The following partition type GUIDs are
    identified:</para>

    <table>
      <title>Partition Type GUIDs</title>
      <tgroup cols='5' align='left' colsep='1' rowsep='1'>
        <colspec colname="type" />
        <colspec colname="guid" />
        <colspec colname="name" />
        <colspec colname="where" />
        <colspec colname="explanation" />
        <thead>
          <row>
            <entry>Partition Type</entry>
            <entry>GUID</entry>
            <entry>Name</entry>
            <entry>Mount Point</entry>
            <entry>Explanation</entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry><constant>SD_GPT_ROOT_X86_64</constant></entry>
            <entry><constant>4f68bce3-e8cd-4db1-96e7-fbcaf984b709</constant></entry>
            <entry><filename>Root Partition (x86-64)</filename></entry>
            <entry><filename>/</filename></entry>
            <entry>The first partition with this type UUID, located on the same disk as the ESP used for booting, is used as the root file system <filename>/</filename> on AMD64 / 64-bit x86 systems.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_ROOT_ARM64</constant></entry>
            <entry><constant>b921b045-1df0-41c3-af44-4c6f280d3fae</constant></entry>
            <entry><filename>Root Partition (64-bit ARM)</filename></entry>
            <entry><filename>/</filename></entry>
            <entry>The first partition with this type UUID, located on the same disk as the ESP used for booting, is used as the root file system <filename>/</filename> on AArch64 / 64-bit ARM systems.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_ROOT_ALPHA</constant> <constant>SD_GPT_ROOT_ARC</constant> <constant>SD_GPT_ROOT_ARM</constant> <constant>SD_GPT_ROOT_ARM64</constant> <constant>SD_GPT_ROOT_IA64</constant> <constant>SD_GPT_ROOT_LOONGARCH64</constant> <constant>SD_GPT_ROOT_MIPS</constant> <constant>SD_GPT_ROOT_MIPS64</constant> <constant>SD_GPT_ROOT_MIPS_LE</constant> <constant>SD_GPT_ROOT_MIPS64_LE</constant> <constant>SD_GPT_ROOT_PARISC</constant> <constant>SD_GPT_ROOT_PPC</constant> <constant>SD_GPT_ROOT_PPC64</constant> <constant>SD_GPT_ROOT_PPC64_LE</constant> <constant>SD_GPT_ROOT_RISCV32</constant> <constant>SD_GPT_ROOT_RISCV64</constant> <constant>SD_GPT_ROOT_S390</constant> <constant>SD_GPT_ROOT_S390X</constant> <constant>SD_GPT_ROOT_TILEGX</constant> <constant>SD_GPT_ROOT_X86</constant> <constant>SD_GPT_ROOT_X86_64</constant> <constant>SD_GPT_USR_ALPHA</constant> <constant>SD_GPT_USR_ARC</constant> <constant>SD_GPT_USR_ARM</constant> <constant>SD_GPT_USR_IA64</constant> <constant>SD_GPT_USR_LOONGARCH64</constant> <constant>SD_GPT_USR_MIPS_LE</constant> <constant>SD_GPT_USR_MIPS64_LE</constant> <constant>SD_GPT_USR_PARISC</constant> <constant>SD_GPT_USR_PPC</constant> <constant>SD_GPT_USR_PPC64</constant> <constant>SD_GPT_USR_PPC64_LE</constant> <constant>SD_GPT_USR_RISCV32</constant> <constant>SD_GPT_USR_RISCV64</constant> <constant>SD_GPT_USR_S390</constant> <constant>SD_GPT_USR_S390X</constant> <constant>SD_GPT_USR_TILEGX</constant> <constant>SD_GPT_USR_X86</constant></entry>
            <entry>…</entry>
            <entry>Root partitions for other architectures</entry>
            <entry><filename>/</filename></entry>
            <entry>The first partition with the type UUID matching the architecture, located on the same disk as the ESP used for booting, is used as the root file system <filename>/</filename>. For the full list and constant values, see <ulink url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification">UAPI.2 Discoverable Partitions Specification</ulink>.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_HOME</constant></entry>
            <entry><constant>933ac7e1-2eb4-4f13-b844-0e14e2aef915</constant></entry>
            <entry>Home Partition</entry>
            <entry><filename>/home/</filename></entry>
            <entry>The first partition with this type UUID on the same disk as the root partition is mounted to <filename>/home/</filename>.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_SRV</constant></entry>
            <entry><constant>3b8f8425-20e0-4f3b-907f-1a25a76f98e8</constant></entry>
            <entry>Server Data Partition</entry>
            <entry><filename>/srv/</filename></entry>
            <entry>The first partition with this type UUID on the same disk as the root partition is mounted to <filename>/srv/</filename>.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_VAR</constant></entry>
            <entry><constant>4d21b016-b534-45c2-a9fb-5c16e091fd2d</constant></entry>
            <entry>Variable Data Partition</entry>
            <entry><filename>/var/</filename></entry>
            <entry>The first partition with this type UUID on the same disk as the root partition is mounted to <filename>/var/</filename> — under the condition its partition UUID matches the first 128 bit of the HMAC-SHA256 of the GPT type uuid of this partition keyed by the machine ID of the installation stored in <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>. This can be generated using <citerefentry><refentrytitle>systemd-id128</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_TMP</constant></entry>
            <entry><constant>7ec6f557-3bc5-4aca-b293-16ef5df639d1</constant></entry>
            <entry>Temporary Data Partition</entry>
            <entry><filename>/var/tmp/</filename></entry>
            <entry>The first partition with this type UUID on the same disk as the root partition is mounted to <filename>/var/tmp/</filename>.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_SWAP</constant></entry>
            <entry><constant>0657fd6d-a4ab-43c4-84e5-0933c84b4f4f</constant></entry>
            <entry>Swap</entry>
            <entry>n/a</entry>
            <entry>All partitions with this type UUID on the same disk as the root partition are used as swap.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_ESP</constant></entry>
            <entry><constant>c12a7328-f81f-11d2-ba4b-00a0c93ec93b</constant></entry>
            <entry>EFI System Partition (ESP)</entry>
            <entry><filename>/efi/</filename> or <filename>/boot/</filename></entry>
            <entry>The first partition with this type UUID located on the same disk as the root partition is mounted to <filename>/boot/</filename> or <filename>/efi/</filename>, see below.</entry>
          </row>
          <row>
            <entry><constant>SD_GPT_XBOOTLDR</constant></entry>
            <entry><constant>bc13c2ff-59e6-4262-a352-b275fd6f7172</constant></entry>
            <entry>Extended Boot Loader Partition</entry>
            <entry><filename>/boot/</filename></entry>
            <entry>The first partition with this type UUID located on the same disk as the root partition is mounted to <filename>/boot/</filename>, see below.</entry>
          </row>
        </tbody>
      </tgroup>
    </table>

    <para>This generator understands the following attribute flags for partitions:</para>

    <table>
      <title>Partition Attribute Flags</title>
      <tgroup cols='4' align='left' colsep='1' rowsep='1'>
        <colspec colname="flag" />
        <colspec colname="value" />
        <colspec colname="where" />
        <colspec colname="explanation" />
        <thead>
          <row>
            <entry>Flag</entry>
            <entry>Value</entry>
            <entry>Applicable to</entry>
            <entry>Explanation</entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry><constant>SD_GPT_FLAG_READ_ONLY</constant></entry>
            <entry><constant>0x1000000000000000</constant></entry>
            <entry><filename>/</filename>, <filename>/home/</filename>, <filename>/srv/</filename>, <filename>/var/</filename>, <filename>/var/tmp/</filename>, Extended Boot Loader Partition</entry>
            <entry>Partition is mounted read-only</entry>
          </row>

          <row>
            <entry><constant>SD_GPT_FLAG_NO_AUTO</constant></entry>
            <entry><constant>0x8000000000000000</constant></entry>
            <entry><filename>/</filename>, <filename>/home/</filename>, <filename>/srv/</filename>, <filename>/var/</filename>, <filename>/var/tmp/</filename>, Extended Boot Loader Partition</entry>
            <entry>Partition is not mounted automatically</entry>
          </row>

          <row>
            <entry><constant>SD_GPT_FLAG_NO_BLOCK_IO_PROTOCOL</constant></entry>
            <entry><constant>0x0000000000000002</constant></entry>
            <entry>EFI System Partition (ESP)</entry>
            <entry>Partition is not mounted automatically</entry>
          </row>
        </tbody>
      </tgroup>
    </table>

    <para>The <filename>/home/</filename>, <filename>/srv/</filename>, <filename>/var/</filename>,
    <filename>/var/tmp/</filename> and swap partitions may be encrypted in LUKS format. In this case, a
    device mapper device is set up under the names <filename>/dev/mapper/home</filename>,
    <filename>/dev/mapper/srv</filename>, <filename>/dev/mapper/var</filename>,
    <filename>/dev/mapper/tmp</filename> or <filename>/dev/mapper/swap</filename>. Note that this might
    create conflicts if the same partition is listed in <filename>/etc/crypttab</filename> with a different
    device mapper device name.</para>

    <para>When systemd is running in the initrd the <filename>/</filename> partition may be encrypted with
    LUKS as well. In this case, a device mapper device is set up under the name
    <filename>/dev/mapper/root</filename>, and a <filename>sysroot.mount</filename> is set up that mounts the
    device under <filename>/sysroot</filename>. For more information, see
    <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
    </para>

    <para>Mount and automount units for the EFI System Partition (ESP) and Extended Boot Loader Partition
    (XBOOTLDR) are generated on EFI systems. If the disk contains an XBOOTLDR partition, as defined in the
    <ulink url="https://uapi-group.org/specifications/specs/boot_loader_specification">UAPI.1 Boot Loader
    Specification</ulink>, it is made available at <filename>/boot/</filename>. This generator creates an
    automount unit; the mount will only be activated on-demand when accessed. The mount point will be created
    if necessary.</para>

    <para>The ESP is mounted to <filename>/boot/</filename> if that directory exists and is not used for
    XBOOTLDR, and otherwise to <filename>/efi/</filename>. Same as for <filename>/boot/</filename>, an
    automount unit is used. The mount point will be created if necessary.</para>

    <para>No configuration is created for mount points that are configured in <citerefentry
    project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry> or when
    the target directory contains files.</para>

    <para>When using this generator in conjunction with btrfs file
    systems, make sure to set the correct default subvolumes on them,
    using <command>btrfs subvolume set-default</command>.</para>

    <para>If the system was booted via
    <citerefentry><refentrytitle>systemd-stub</refentrytitle><manvolnum>7</manvolnum></citerefentry> and the
    stub reported to userspace that the kernel image was measured to a TPM2 PCR, then any discovered root and
    <filename>/var/</filename> volume identifiers (and volume encryption key in case it is encrypted) will be
    automatically measured into PCR 15 on activation, via
    <citerefentry><refentrytitle>systemd-pcrfs@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>

    <para>Mount constraint metadata contained in the file systems is validated by pulling in
    <citerefentry><refentrytitle>systemd-validatefs@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    for generated mounts.</para>

    <para><filename>systemd-gpt-auto-generator</filename> implements
    <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
  </refsect1>

  <refsect1>
    <title>Kernel Command Line</title>

    <para><filename>systemd-gpt-auto-generator</filename> understands the following kernel command line
    parameters:</para>

    <variablelist class='kernel-commandline-options'>

      <varlistentry>
        <term><varname>systemd.gpt_auto</varname></term>
        <term><varname>rd.systemd.gpt_auto</varname></term>

        <listitem><para>Those options take an optional boolean argument, and default to yes.
        The generator is enabled by default, and a false value may be used to disable it
        (e.g. <literal>systemd.gpt_auto=0</literal>).
        </para>

        <xi:include href="version-info.xml" xpointer="v242"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>systemd.image_policy=</varname></term>

        <listitem><para>Takes an image dissection policy string as argument (as per
        <citerefentry><refentrytitle>systemd.image-policy</refentrytitle><manvolnum>7</manvolnum></citerefentry>),
        and allows enforcing a policy on dissection and use of the automatically discovered GPT partition
        table entries.</para>

        <para>Note that the specified image policy is not taken into account for automatic root or
        <filename>/usr/</filename> file system discovery unless
        <varname>root=dissect</varname>/<varname>mount.usr=dissect</varname> (or
        <varname>root=dissect-force</varname>) are specified. (The policy will always be applied to the other
        auto-discoverable partition types.)</para>

        <xi:include href="version-info.xml" xpointer="v254"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>systemd.image_filter=</varname></term>

        <listitem><para>Takes an image dissection filter string as argument (as per
        <citerefentry><refentrytitle>systemd.image-filter</refentrytitle><manvolnum>7</manvolnum></citerefentry>),
        and allows enforcing a set of globbing patterns on the partition matching of the automatically
        discovered GPT partition table entries.</para>

        <para>Note that the specified image filter is not taken into account for automatic root or
        <filename>/usr/</filename> file system discovery unless
        <varname>root=dissect</varname>/<varname>mount.usr=dissect</varname> (or
        <varname>root=dissect-force</varname>) are specified. (The filter will always be applied to the other
        auto-discoverable partition types.)</para>

        <xi:include href="version-info.xml" xpointer="v258"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>root=</varname></term>
        <term><varname>rootfstype=</varname></term>
        <term><varname>rootflags=</varname></term>

        <listitem><para>When <varname>root=</varname> is used with the special value
        <literal>gpt-auto</literal>, basic automatic discovery of the root partition based on the GPT
        partition type is enabled. Use of the root partition is delayed until factory reset mode is left, in
        case it is enabled during the current boot. See <ulink url="https://systemd.io/FACTORY_RESET">Factory
        Reset</ulink> for more information on that. If <literal>gpt-auto-force</literal> is specified
        automatic discovery of the root partition is enabled, ignoring any factory reset mode.</para>

        <para>If <varname>root=</varname> is set to the special value <literal>dissect</literal> full
        automatic discovery of the root partition based on GPT partition information is enabled. This is a
        superset of <varname>root=gpt-auto</varname>, as it automatically configures Verity partitions
        (including signature-based setup) following the logic defined for that in the <ulink
        url="https://uapi-group.org/specifications/specs/discoverable_partitions_specification/">UAPI.2 Discoverable
        Partitions Specification</ulink>. Moreover it takes the configured image policy and image filter into
        account for all partition types, including the root file system. <literal>root=dissect</literal> will
        wait for the factory reset phase to be completed if it is in effect before activating the root file
        system. Use <literal>root=dissect-force</literal> to ignore the factory reset phase and activate the
        root file system immediately.</para>

        <para>Any other value (i.e. besides <literal>gpt-auto</literal>, <literal>gpt-auto-force</literal>,
        <literal>dissect</literal>, <literal>dissect-force</literal>) disables automatic root file system
        discovery.</para>

        <para>If <varname>root=</varname> is not specified at all on the kernel command line automatic
        discovery of the root partition via the ESP reported by the boot loader is also enabled (taking
        factory reset state into account, i.e. equivalent to <literal>root=gpt-auto</literal>), however in
        this case discovery based on the loopback block device <literal>.lo_name</literal> field is not
        enabled.</para>

        <para>The <varname>rootfstype=</varname> and <varname>rootflags=</varname> options are used to select
        the file system type and options when the root file system is automatically discovered.</para>

        <xi:include href="version-info.xml" xpointer="v242"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>mount.usr=</varname></term>
        <term><varname>mount.usrfstype=</varname></term>
        <term><varname>mount.usrflags=</varname></term>

        <listitem><para>Similar to <varname>root=</varname>, <varname>rootfstype=</varname>,
        <varname>rootflags=</varname> (see above), but applies to the <filename>/usr/</filename> partition
        instead. Note that the <literal>gpt-auto</literal>, <literal>gpt-auto-force</literal>,
        <literal>dissect-force</literal> settings that <filename>root=</filename> understands are not
        supported by <varname>mount.usr=</varname> (however <literal>dissect</literal> is).</para>

        <para>Also note that automatic partition discovery for <filename>/usr/</filename> must be enabled
        explicitly, unlike the discovery for the root file system, which is enabled if no
        <varname>root=</varname> parameter is passed at all.</para>

        <xi:include href="version-info.xml" xpointer="v258"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>rw</varname></term>
        <term><varname>ro</varname></term>

        <listitem><para>Mount the root partition read-write or read-only <emphasis>initially</emphasis>.</para>

        <para>Note that unlike most kernel command line options these settings do not override configuration
        in the file system, and the file system may be remounted later. See
        <citerefentry><refentrytitle>systemd-remount-fs.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
        </para>

        <xi:include href="version-info.xml" xpointer="v242"/></listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>systemd.swap=</varname></term>

        <listitem><para>Takes a boolean argument or enables the option if specified without an argument.
        If disabled, automatic discovery of swap partition(s) based on GPT partition type is disabled.
        Defaults to enabled.</para>

        <xi:include href="version-info.xml" xpointer="v254"/></listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para><simplelist type="inline">
      <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd-cryptsetup@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd-pcrfs@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>systemd-validatefs@.service</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
      <member><citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
      <member><citerefentry project='die-net'><refentrytitle>cryptsetup</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
      <member><citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
      <member><citerefentry project='url'><refentrytitle url='https://btrfs.readthedocs.io/en/latest/btrfs.html'>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
    </simplelist></para>
  </refsect1>

</refentry>