systemd/man/systemd-repart.xml
Zbigniew Jędrzejewski-Szmek d202ea5754 man/systemd-repart: extend description and reword some sentences
The page was written when systemd-repart was primarily intended to be used on a
running system. But nowadays it's more often used to create images, so extend
that part of the description.

While at it, fix some whitespace issues and trim some overly complicated sentences.
2024-07-22 12:14:23 +01:00

709 lines
38 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-repart" conditional='ENABLE_REPART'
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-repart</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-repart</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-repart</refname>
<refname>systemd-repart.service</refname>
<refpurpose>Automatically grow and add partitions, and generate disk images (DDIs).</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>systemd-repart</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="opt" rep="repeat"><replaceable><optional>BLOCKDEVICE</optional></replaceable></arg>
</cmdsynopsis>
<para><filename>systemd-repart.service</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>systemd-repart</command> creates partition tables, and adds or grows partitions,
based on the configuration files described in
<citerefentry><refentrytitle>repart.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para>
<para><command>systemd-repart</command> is used when <emphasis>building</emphasis> OS images, and also
when <emphasis>deploying</emphasis> images to automatically adjust them, during boot, to the system they
are running on. This way the image can be minimal in size and may be augmented automatically at boot,
taking possession of the disk space available.</para>
<para>If invoked with no arguments, <command>systemd-repart</command> operates on the block device
backing the root file system partition of the running OS, thus adding and growing partitions of the
booted OS itself. When called in the initrd, it operates on the block device backing
<filename>/sysroot/</filename> instead, i.e. on the block device the system will soon transition into. If
<varname>--image=</varname> is used, it will operate on the specified device or image file. The
<filename>systemd-repart.service</filename> service is generally run at boot in the initrd, in order to
augment the partition table of the OS before its partitions are mounted.</para>
<para><command>systemd-repart</command> operations are mostly incremental: it grows existing partitions
or adds new ones, but does not shrink, delete, or move existing partitions. The service is intended to be
run on every boot, but when it detects that the partition table already matches the installed
<filename>repart.d/*.conf</filename> configuration files, it executes no operation.</para>
<para>The following use cases are among those covered:</para>
<itemizedlist>
<listitem><para>The root partition may be grown to cover the whole available disk space.</para></listitem>
<listitem><para>A <filename>/home/</filename>, swap, or <filename>/srv/</filename> partition can be
added.</para></listitem>
<listitem><para>A second (or third, …) root partition may be added, to cover A/B style setups
where a second version of the root file system is alternatingly used for implementing update
schemes. The deployed image would carry only a single partition ("A") but on first boot a second
partition ("B") for this purpose is automatically created.</para></listitem>
</itemizedlist>
<para>The algorithm executed by <command>systemd-repart</command> is roughly as follows:</para>
<orderedlist>
<listitem><para>The <filename>repart.d/*.conf</filename> configuration files are loaded and parsed, and
ordered by filename (without the directory prefix). For each configuration file, drop-in files are
loaded from directories with same name as the configuration file with the suffix ".d" added.
</para></listitem>
<listitem><para>The partition table on the block device is loaded and parsed, if present.
</para></listitem>
<listitem><para>The existing partitions in the partition table are matched with the
<filename>repart.d/*.conf</filename> files by GPT partition type UUID. The first existing partition of
a specific type is assigned the first configuration file declaring the same type. The second existing
partition of a specific type is then assigned the second configuration file declaring the same type,
and so on. After this iterative assigning is complete, any existing partitions that have no matching
configuration file are considered "foreign" and left as they are. And any configuration files for which
no partition was matched are treated as requests to create a partition.</para></listitem>
<listitem><para>Partitions that shall be created are now allocated on the disk, taking the size
constraints and weights declared in the configuration files into account. Free space is used within the
limits set by size and padding requests. In addition, existing partitions that should be grown are
grown. New partitions are always appended to the end of the partition table, taking the first partition
table slot whose index is greater than the indexes of all existing partitions. Partitions are never
reordered and thus partition numbers remain stable. When partitions are created, they are placed in the
smallest area of free space that is large enough to satisfy the size and padding limits. This means
that partitions might have different order on disk than in the partition table. Note that this
allocation happens in memory only, the partition table on disk is not updated yet.</para></listitem>
<listitem><para>All existing partitions for which configuration files exist and which currently have no
GPT partition label set will be assigned a label, either explicitly configured in the configuration or
— if that's missing — derived automatically from the partition type. The same is done for all
partitions that are newly created. These assignments are done in memory only, too, the disk is not
updated yet.</para></listitem>
<listitem><para>Similarly, all existing partitions for which configuration files exist and which
currently have an all-zero identifying UUID will be assigned a new UUID. This UUID is cryptographically
hashed from a common seed value together with the partition type UUID (and a counter in case multiple
partitions of the same type are defined), see below. The same is done for all partitions that are
created anew. These assignments are done in memory only, too, the disk is not updated yet.
</para></listitem>
<listitem><para>Similarly, if the disk's volume UUID is all zeroes it is also initialized, also
cryptographically hashed from the same common seed value. This is done in memory only too.
</para></listitem>
<listitem><para>The disk space assigned to new partitions (i.e. what was previously free space) is now
erased. Specifically, all file system signatures are removed, and if the device supports it, the
<constant>BLKDISCARD</constant> I/O control command is issued to inform the hardware that the space is
now empty. In addition any "padding" between partitions and at the end of the device is similarly
erased.</para></listitem>
<listitem><para>The new partition table is finally written to disk. The kernel is asked to reread the
partition table.</para></listitem>
</orderedlist>
<para>As an exception to the normal incremental operation, when called in a special "factory reset" mode,
<command>systemd-repart</command> may be used to erase existing partitions to reset an installation back
to vendor defaults. This mode of operation is used when either the <option>--factory-reset=yes</option>
switch is passed on the tool's command line, or the <option>systemd.factory_reset=yes</option> option is
specified on the kernel command line, or the <varname>FactoryReset</varname> EFI variable (vendor UUID
<constant>8cf2644b-4b0b-428f-9387-6d876050dc67</constant>) is set to "yes". It alters the algorithm above
slightly: between the 3rd and the 4th step above any partition marked explicitly via the
<varname>FactoryReset=</varname> boolean is deleted, and the algorithm restarted, thus immediately
re-creating these partitions anew empty.</para>
<para>Note that <command>systemd-repart</command> by default only changes partition tables, it does not
create or resize any file systems within these partitions, unless the <varname>Format=</varname>
configuration option is specified. Also note that there are also separate mechanisms available for this
purpose, for example
<citerefentry><refentrytitle>systemd-growfs</refentrytitle><manvolnum>8</manvolnum></citerefentry> and
<command>systemd-makefs</command>.</para>
<para>The UUIDs identifying the new partitions created (or assigned to existing partitions that have no
UUID yet), as well as the disk as a whole are hashed cryptographically from a common seed value. This
seed value is usually the
<citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> of the
system, so that the machine ID reproducibly determines the UUIDs assigned to all partitions. If the
machine ID cannot be read (or the user passes <option>--seed=random</option>, see below) the seed is
generated randomly instead, so that the partition UUIDs are also effectively random. The seed value may
also be set explicitly, formatted as UUID via the <option>--seed=</option> option. By hashing these UUIDs
from a common seed images prepared with this tool become reproducible and the result of the algorithm
above deterministic.</para>
<para>The positional argument should specify the block device or a regular file to operate on. If
<option>--empty=create</option> is specified, the specified path is created as regular file, which is
useful for generating disk images from scratch.</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<varlistentry>
<term><option>--dry-run=</option></term>
<listitem><para>Takes a boolean. If this switch is not specified <option>--dry-run=yes</option> is
the implied default. Controls whether <filename>systemd-repart</filename> executes the requested
re-partition operations or whether it should only show what it would do. Unless
<option>--dry-run=no</option> is specified <filename>systemd-repart</filename> will not actually
touch the device's partition table.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--empty=</option></term>
<listitem><para>Takes one of <literal>refuse</literal>, <literal>allow</literal>,
<literal>require</literal>, <literal>force</literal> or <literal>create</literal>. Controls how to
operate on block devices that are entirely empty, i.e. carry no partition table/disk label yet. If
this switch is not specified the implied default is <literal>refuse</literal>.</para>
<para>If <literal>refuse</literal> <command>systemd-repart</command> requires that the block device
it shall operate on already carries a partition table and refuses operation if none is found. If
<literal>allow</literal> the command will extend an existing partition table or create a new one if
none exists. If <literal>require</literal> the command will create a new partition table if none
exists so far, and refuse operation if one already exists. If <literal>force</literal> it will create
a fresh partition table unconditionally, erasing the disk fully in effect. If
<literal>force</literal> no existing partitions will be taken into account or survive the
operation. Hence: use with care, this is a great way to lose all your data. If
<literal>create</literal> a new loopback file is create under the path passed via the device node
parameter, of the size indicated with <option>--size=</option>, see below.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--discard=</option></term>
<listitem><para>Takes a boolean. If this switch is not specified <option>--discard=yes</option> is
the implied default. Controls whether to issue the <constant>BLKDISCARD</constant> I/O control
command on the space taken up by any added partitions or on the space in between them. Usually, it's
a good idea to issue this request since it tells the underlying hardware that the covered blocks
shall be considered empty, improving performance. If operating on a regular file instead of a block
device node, a sparse file is generated.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--size=</option></term>
<listitem><para>Takes a size in bytes, using the usual K, M, G, T suffixes, or the special value
<literal>auto</literal>. If used the specified device node path must refer to a regular file, which
is then grown to the specified size if smaller, before any change is made to the partition table. If
specified as <literal>auto</literal> the minimal size for the disk image is automatically determined
(i.e. the minimal sizes of all partitions are summed up, taking space for additional metadata into
account). This switch is not supported if the specified node is a block device. This switch has no
effect if the file is already as large as the specified size or larger. The specified size is
implicitly rounded up to multiples of 4096. When used with <option>--empty=create</option> this
specifies the initial size of the loopback file to create.</para>
<para>The <option>--size=auto</option> option takes the sizes of pre-existing partitions into
account. However, it does not accommodate for partition tables that are not tightly packed: the
configured partitions might still not fit into the backing device if empty space exists between
pre-existing partitions (or before the first partition) that cannot be fully filled by partitions to
grow or create.</para>
<para>Also note that the automatic size determination does not take files or directories specified
with <option>CopyFiles=</option> into account: operation might fail if the specified files or
directories require more disk space then the configured per-partition minimal size
limit.</para>
<xi:include href="version-info.xml" xpointer="v246"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--factory-reset=</option></term>
<listitem><para>Takes boolean. If this switch is not specified <option>--factory=reset=no</option> is
the implied default. Controls whether to operate in "factory reset" mode, see above. If set to true
this will remove all existing partitions marked with <varname>FactoryReset=</varname> set to yes
early while executing the re-partitioning algorithm. Use with care, this is a great way to lose all
your data. Note that partition files need to explicitly turn <varname>FactoryReset=</varname> on, as
the option defaults to off. If no partitions are marked for factory reset this switch has no
effect. Note that there are two other methods to request factory reset operation: via the kernel
command line and via an EFI variable, see above.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--can-factory-reset</option></term>
<listitem><para>If this switch is specified the disk is not re-partitioned. Instead it is determined
if any existing partitions are marked with <varname>FactoryReset=</varname>. If there are the tool
will exit with exit status zero, otherwise non-zero. This switch may be used to quickly determine
whether the running system supports a factory reset mechanism built on
<command>systemd-repart</command>.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--root=</option></term>
<listitem><para>Takes a path to a directory to use as root file system when searching for
<filename>repart.d/*.conf</filename> files, for the machine ID file to use as seed and for the
<varname>CopyFiles=</varname> and <varname>CopyBlocks=</varname> source files and directories. By
default when invoked on the regular system this defaults to the host's root file system
<filename>/</filename>. If invoked from the initrd this defaults to <filename>/sysroot/</filename>,
so that the tool operates on the configuration and machine ID stored in the root file system later
transitioned into itself.</para>
<para>See <option>--copy-source=</option> for a more restricted option that only affects
<varname>CopyFiles=</varname>.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--image=</option></term>
<listitem><para>Takes a path to a disk image file or device to mount and use in a similar fashion to
<option>--root=</option>, see above.</para>
<xi:include href="version-info.xml" xpointer="v249"/></listitem>
</varlistentry>
<xi:include href="standard-options.xml" xpointer="image-policy-open" />
<varlistentry>
<term><option>--seed=</option></term>
<listitem><para>Takes a UUID as argument or the special value <constant>random</constant>. If a UUID
is specified the UUIDs to assign to partitions and the partition table itself are derived via
cryptographic hashing from it. If not specified it is attempted to read the machine ID from the host
(or more precisely, the root directory configured via <option>--root=</option>) and use it as seed
instead, falling back to a randomized seed otherwise. Use <option>--seed=random</option> to force a
randomized seed. Explicitly specifying the seed may be used to generated strictly reproducible
partition tables.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--pretty=</option></term>
<listitem><para>Takes a boolean argument. If this switch is not specified, it defaults to on when
called from an interactive terminal and off otherwise. Controls whether to show a user friendly table
and graphic illustrating the changes applied.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--definitions=</option></term>
<listitem><para>Takes a file system path. If specified the <filename>*.conf</filename> files are read
from the specified directory instead of searching in <filename>/usr/lib/repart.d/*.conf</filename>,
<filename>/etc/repart.d/*.conf</filename>,
<filename>/run/repart.d/*.conf</filename>.</para>
<para>This parameter can be specified multiple times.</para>
<xi:include href="version-info.xml" xpointer="v245"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--key-file=</option></term>
<listitem><para>Takes a file system path. Configures the encryption key to use when setting up LUKS2
volumes configured with the <varname>Encrypt=key-file</varname> setting in partition files. Should
refer to a regular file containing the key, or an <constant>AF_UNIX</constant> stream socket in the
file system. In the latter case a connection is made to it and the key read from it. If this switch
is not specified the empty key (i.e. zero length key) is used. This behaviour is useful for setting
up encrypted partitions during early first boot that receive their user-supplied password only in a
later setup step.</para>
<xi:include href="version-info.xml" xpointer="v247"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--private-key=</option></term>
<listitem><para>Takes a file system path. Configures the signing key to use when creating verity
signature partitions with the <varname>Verity=signature</varname> setting in partition files.
</para>
<xi:include href="version-info.xml" xpointer="v252"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--private-key-source=</option></term>
<listitem><para>Takes one of <literal>file</literal>, <literal>engine</literal> or
<literal>provider</literal>. In the latter two cases, it is followed by the name of a provider or
engine, separated by colon, that will be passed to OpenSSL's "engine" or "provider" logic.
Configures the signing mechanism to use when creating verity signature partitions with the
<varname>Verity=signature</varname> setting in partition files.</para>
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--certificate=</option></term>
<listitem><para>Takes a file system path. Configures the PEM encoded X.509 certificate to use when
creating verity signature partitions with the <varname>Verity=signature</varname> setting in
partition files.</para>
<xi:include href="version-info.xml" xpointer="v252"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--tpm2-device=</option></term>
<term><option>--tpm2-pcrs=</option></term>
<listitem><para>Configures the TPM2 device and list of PCRs to use for LUKS2 volumes configured with
the <varname>Encrypt=tpm2</varname> option. These options take the same parameters as the identically
named options to
<citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry>
and have the same effect on partitions where TPM2 enrollment is requested.</para>
<xi:include href="version-info.xml" xpointer="v248"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--tpm2-device-key=<replaceable>PATH</replaceable></option></term>
<term><option>--tpm2-seal-key-handle=<replaceable>HANDLE</replaceable></option></term>
<listitem><para>Configures a TPM2 SRK key to bind encryption to. See
<citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry>
for details on this option.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--tpm2-public-key=<replaceable>PATH</replaceable></option></term>
<term><option>--tpm2-public-key-pcrs=<replaceable>PCR<optional>+PCR...</optional></replaceable></option></term>
<listitem><para>Configures a TPM2 signed PCR policy to bind encryption to. See
<citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry>
for details on these two options.</para>
<xi:include href="version-info.xml" xpointer="v252"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--tpm2-pcrlock=<replaceable>PATH</replaceable></option></term>
<listitem><para>Configures a TPM2 pcrlock policy to bind encryption to. See
<citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry>
for details on this option.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--split=<replaceable>BOOL</replaceable></option></term>
<listitem><para>Enables generation of split artifacts from partitions configured with
<varname>SplitName=</varname>. If enabled, for each partition with <varname>SplitName=</varname> set,
a separate output file containing just the contents of that partition is generated. The output
filename consists of the loopback filename suffixed with the name configured with
<varname>SplitName=</varname>. If the loopback filename ends with <literal>.raw</literal>, the suffix
is inserted before the <literal>.raw</literal> extension instead.</para>
<para>Note that <option>--split</option> is independent from <option>--dry-run</option>. Even if
<option>--dry-run</option> is enabled, split artifacts will still be generated from an existing image
if <option>--split</option> is enabled.</para>
<xi:include href="version-info.xml" xpointer="v252"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--include-partitions=<replaceable>PARTITIONS</replaceable></option></term>
<term><option>--exclude-partitions=<replaceable>PARTITIONS</replaceable></option></term>
<listitem><para>These options specify which partition types <command>systemd-repart</command> should
operate on. If <option>--include-partitions=</option> is used, all partitions that aren't specified
are excluded. If <option>--exclude-partitions=</option> is used, all partitions that are specified
are excluded. Both options take a comma separated list of GPT partition type UUIDs or identifiers
(see <varname>Type=</varname> in
<citerefentry><refentrytitle>repart.d</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
</para>
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--defer-partitions=<replaceable>PARTITIONS</replaceable></option></term>
<listitem><para>This option specifies for which partition types <command>systemd-repart</command>
should defer. All partitions that are deferred using this option are still taken into account when
calculating the sizes and offsets of other partitions, but aren't actually written to the disk image.
The net effect of this option is that if you run <command>systemd-repart</command> again without this
option, the missing partitions will be added as if they had not been deferred the first time
<command>systemd-repart</command> was executed.</para>
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--sector-size=<replaceable>BYTES</replaceable></option></term>
<listitem><para>This option allows configuring the sector size of the image produced by
<command>systemd-repart</command>. It takes a value that is a power of <literal>2</literal> between
<literal>512</literal> and <literal>4096</literal>. This option is useful when building images for
disks that use a different sector size as the disk on which the image is produced.</para>
<xi:include href="version-info.xml" xpointer="v253"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--architecture=<replaceable>ARCH</replaceable></option></term>
<listitem><para>This option allows overriding the architecture used for architecture specific
partition types. For example, if set to <literal>arm64</literal> a partition type of
<literal>root-x86-64</literal> referenced in <filename>repart.d/</filename> drop-ins will be patched
dynamically to refer to <literal>root-arm64</literal> instead. Takes one of
<literal>alpha</literal>,
<literal>arc</literal>,
<literal>arm</literal>,
<literal>arm64</literal>,
<literal>ia64</literal>,
<literal>loongarch64</literal>,
<literal>mips-le</literal>,
<literal>mips64-le</literal>,
<literal>parisc</literal>,
<literal>ppc</literal>,
<literal>ppc64</literal>,
<literal>ppc64-le</literal>,
<literal>riscv32</literal>,
<literal>riscv64</literal>,
<literal>s390</literal>,
<literal>s390x</literal>,
<literal>tilegx</literal>,
<literal>x86</literal> or
<literal>x86-64</literal>.</para>
<xi:include href="version-info.xml" xpointer="v254"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--offline=<replaceable>BOOL</replaceable></option></term>
<listitem><para>Instructs <command>systemd-repart</command> to build the image offline. Takes a
boolean or <literal>auto</literal>. Defaults to <literal>auto</literal>. If enabled, the image is
built without using loop devices. This is useful to build images unprivileged or when loop devices
are not available. If disabled, the image is always built using loop devices. If
<literal>auto</literal>, <command>systemd-repart</command> will build the image online if possible
and fall back to building the image offline if loop devices are not available or cannot be accessed
due to missing permissions.</para>
<xi:include href="version-info.xml" xpointer="v254"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--copy-from=<replaceable>IMAGE</replaceable></option></term>
<listitem><para>Instructs <command>systemd-repart</command> to synthesize partition definitions from
the partition table in the given image. This option can be specified multiple times to synthesize
definitions from each of the given images. The generated definitions will copy the partitions into
the destination partition table. The copied partitions will have the same size, metadata and contents
but might have a different partition number and might be located at a different offset in the
destination partition table. These definitions can be combined with partition definitions read from
regular partition definition files. The synthesized definitions take precedence over the definitions
read from partition definition files.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--copy-source=<replaceable>PATH</replaceable></option></term>
<term><option>-s</option> <replaceable>PATH</replaceable></term>
<listitem><para>Specifies a source directory all <varname>CopyFiles=</varname> source paths shall be
considered relative to. This is similar to <option>--root=</option>, but exclusively applies to the
<varname>CopyFiles=</varname> setting. If <option>--root=</option> and
<option>--copy-source=</option> are used in combination the former applies as usual, except for
<varname>CopyFiles=</varname> where the latter takes precedence.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--make-ddi=<replaceable>TYPE</replaceable></option></term>
<listitem><para>Takes one of <literal>sysext</literal>, <literal>confext</literal> or
<literal>portable</literal>. Generates a Discoverable Disk Image (DDI) for a system extension
(sysext, see
<citerefentry><refentrytitle>systemd-sysext</refentrytitle><manvolnum>8</manvolnum></citerefentry>
for details), configuration extension (confext) or <ulink
url="https://systemd.io/PORTABLE_SERVICES">portable service</ulink>. The generated image will consist
of a signed Verity <literal>erofs</literal> file system as root partition. In this mode of operation
the partition definitions in <filename>/usr/lib/repart.d/*.conf</filename> and related directories
are not read, and <option>--definitions=</option> is not supported, as appropriate definitions for
the selected DDI class will be chosen automatically.</para>
<para>Must be used in conjunction with <option>--copy-source=</option> to specify the file hierarchy
to populate the DDI with. The specified directory should contain an <filename>etc/</filename>
subdirectory if <literal>confext</literal> is selected. If <literal>sysext</literal> is selected it
should contain either a <filename>usr/</filename> or <filename>opt/</filename> directory, or both. If
<literal>portable</literal> is used a full OS file hierarchy can be provided.</para>
<para>This option implies <option>--empty=create</option>, <option>--size=auto</option> and
<option>--seed=random</option> (the latter two can be overridden).</para>
<para>The private key and certificate for signing the DDI must be specified via the
<option>--private-key=</option> and <option>--certificate=</option> switches.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>-S</option></term>
<term><option>-C</option></term>
<term><option>-P</option></term>
<listitem><para>Shortcuts for <option>--make-ddi=sysext</option>,
<option>--make-ddi=confext</option>, <option>--make-ddi=portable</option>,
respectively.</para>
<xi:include href="version-info.xml" xpointer="v255"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--generate-fstab=<replaceable>PATH</replaceable></option></term>
<listitem><para>Specifies a path where to write fstab entries for the mountpoints configured with
<option>MountPoint=</option> in the root directory specified with <option>--copy-source=</option> or
<option>--root=</option> or in the host's root directory if neither is specified. Disabled by
default.</para>
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--generate-crypttab=<replaceable>PATH</replaceable></option></term>
<listitem><para>Specifies a path where to write crypttab entries for the encrypted volumes configured
with <option>EncryptedVolume=</option> in the root directory specified with
<option>--copy-source=</option> or <option>--root=</option> or in the host's root directory if
neither is specified. Disabled by default.</para>
<xi:include href="version-info.xml" xpointer="v256"/></listitem>
</varlistentry>
<varlistentry>
<term><option>--list-devices</option></term>
<listitem><para>Show a list of candidate block devices this command may operate on. Specifically,
this enumerates block devices currently present that support partition tables, and shows their device
node paths along with any of their symlinks.</para>
<xi:include href="version-info.xml" xpointer="v257"/></listitem>
</varlistentry>
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
<xi:include href="standard-options.xml" xpointer="no-pager" />
<xi:include href="standard-options.xml" xpointer="no-legend" />
<xi:include href="standard-options.xml" xpointer="json" />
</variablelist>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, and a non-zero failure code otherwise.</para>
</refsect1>
<refsect1>
<title>Example</title>
<example>
<title>Generate a configuration extension image</title>
<para>The following creates a configuration extension DDI (confext) for an
<filename>/etc/motd</filename> update:</para>
<programlisting>mkdir -p tree/etc/extension-release.d
echo "Hello World" >tree/etc/motd
cat >tree/etc/extension-release.d/extension-release.my-motd &lt;&lt;EOF
ID=fedora
VERSION_ID=38
IMAGE_ID=my-motd
IMAGE_VERSION=7
EOF
systemd-repart -C \
--private-key=privkey.pem \
--certificate=cert.crt \
-s tree/ \
/var/lib/confexts/my-motd.confext.raw
systemd-confext refresh</programlisting>
<para>The DDI generated that way may be applied to the system with
<citerefentry><refentrytitle>systemd-confext</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
</example>
<example>
<title>Generate a system extension image and sign it via PKCS11</title>
<para>The following creates a system extension DDI (sysext) for an
<filename>/usr/foo</filename> update and signs it with a hardware token via PKCS11.</para>
<programlisting>mkdir -p tree/usr/lib/extension-release.d
echo "Hello World" >tree/usr/foo
cat >tree/usr/lib/extension-release.d/extension-release.my-foo &lt;&lt;EOF
ID=fedora
VERSION_ID=38
IMAGE_ID=my-foo
IMAGE_VERSION=7
EOF
systemd-repart --make-ddi=sysext \
--private-key-source=engine:pkcs11 \
--private-key="pkcs11:model=PKCS%2315%20emulated;manufacturer=piv_II;serial=0123456789abcdef;token=Some%20Cert" \
--certificate=cert.crt \
-s tree/ \
/var/lib/extensions/my-foo.sysext.raw
systemd-sysext refresh</programlisting>
<para>The DDI generated that way may be applied to the system with
<citerefentry><refentrytitle>systemd-sysext</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
</example>
</refsect1>
<refsect1>
<title>See Also</title>
<para><simplelist type="inline">
<member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>repart.d</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>systemd-cryptenroll</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>portablectl</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>systemd-sysext</refentrytitle><manvolnum>8</manvolnum></citerefentry></member>
</simplelist></para>
</refsect1>
</refentry>