mirror of
https://github.com/morgan9e/systemd
synced 2026-04-14 00:14:32 +09:00
447 lines
27 KiB
XML
447 lines
27 KiB
XML
<?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">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">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">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/">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> paramater 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>
|