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diff --git a/man/repart.d.xml b/man/repart.d.xml new file mode 100644 index 0000000..6e31843 --- /dev/null +++ b/man/repart.d.xml @@ -0,0 +1,634 @@ +<?xml version='1.0'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<refentry id="repart.d" conditional='ENABLE_REPART' + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>repart.d</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>repart.d</refentrytitle> + <manvolnum>5</manvolnum> + </refmeta> + + <refnamediv> + <refname>repart.d</refname> + <refpurpose>Partition Definition Files for Automatic Boot-Time Repartitioning</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <para><literallayout><filename>/etc/repart.d/*.conf</filename> +<filename>/run/repart.d/*.conf</filename> +<filename>/usr/lib/repart.d/*.conf</filename> + </literallayout></para> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><filename>repart.d/*.conf</filename> files describe basic properties of partitions of block + devices of the local system. They may be used to declare types, names and sizes of partitions that shall + exist. The + <citerefentry><refentrytitle>systemd-repart</refentrytitle><manvolnum>8</manvolnum></citerefentry> + service reads these files and attempts to add new partitions currently missing and enlarge existing + partitions according to these definitions. Operation is generally incremental, i.e. when applied, what + exists already is left intact, and partitions are never shrunk, moved or deleted.</para> + + <para>These definition files are useful for implementing operating system images that are prepared and + delivered with minimally sized images (for example lacking any state or swap partitions), and which on + first boot automatically take possession of any remaining disk space following a few basic rules.</para> + + <para>Currently, support for partition definition files is only implemented for GPT partitition + tables.</para> + + <para>Partition files are generally matched against any partitions already existing on disk in a simple + algorithm: the partition files are sorted by their filename (ignoring the directory prefix), and then + compared in order against existing partitions matching the same partition type UUID. Specifically, the + first existing partition with a specific partition type UUID is assigned the first definition file with + the same partition type UUID, and the second existing partition with a specific type UUID the second + partition file with the same type UUID, and so on. Any left-over partition files that have no matching + existing partition are assumed to define new partition that shall be created. Such partitions are + appended to the end of the partition table, in the order defined by their names utilizing the first + partition slot greater than the highest slot number currently in use. Any existing partitions that have + no matching partition file are left as they are.</para> + + <para>Note that these definitions may only be used to created and initialize new partitions or grow + existing ones. In the latter case it will not grow the contained files systems however; separate + mechanisms, such as + <citerefentry><refentrytitle>systemd-growfs</refentrytitle><manvolnum>8</manvolnum></citerefentry> may be + used to grow the file systems inside of these partitions.</para> + </refsect1> + + <refsect1> + <title>[Partition] Section Options</title> + + <variablelist> + <varlistentry> + <term><varname>Type=</varname></term> + + <listitem><para>The GPT partition type UUID to match. This may be a GPT partition type UUID such as + <constant>4f68bce3-e8cd-4db1-96e7-fbcaf984b709</constant>, or one of the following special + identifiers:</para> + + <table> + <title>GPT partition type identifiers</title> + + <tgroup cols='2' align='left' colsep='1' rowsep='1'> + <colspec colname="name" /> + <colspec colname="explanation" /> + + <thead> + <row> + <entry>Identifier</entry> + <entry>Explanation</entry> + </row> + </thead> + + <tbody> + <row> + <entry><constant>esp</constant></entry> + <entry>EFI System Partition</entry> + </row> + + <row> + <entry><constant>xbootldr</constant></entry> + <entry>Extended Boot Loader Partition</entry> + </row> + + <row> + <entry><constant>swap</constant></entry> + <entry>Swap partition</entry> + </row> + + <row> + <entry><constant>home</constant></entry> + <entry>Home (<filename>/home/</filename>) partition</entry> + </row> + + <row> + <entry><constant>srv</constant></entry> + <entry>Server data (<filename>/srv/</filename>) partition</entry> + </row> + + <row> + <entry><constant>var</constant></entry> + <entry>Variable data (<filename>/var/</filename>) partition</entry> + </row> + + <row> + <entry><constant>tmp</constant></entry> + <entry>Temporary data (<filename>/var/tmp/</filename>) partition</entry> + </row> + + <row> + <entry><constant>linux-generic</constant></entry> + <entry>Generic Linux file system partition</entry> + </row> + + <row> + <entry><constant>root</constant></entry> + <entry>Root file system partition type appropriate for the local architecture (an alias for an architecture root file system partition type listed below, e.g. <constant>root-x86-64</constant>)</entry> + </row> + + <row> + <entry><constant>root-verity</constant></entry> + <entry>Verity data for the root file system partition for the local architecture</entry> + </row> + + <row> + <entry><constant>root-secondary</constant></entry> + <entry>Root file system partition of the secondary architecture of the local architecture (usually the matching 32bit architecture for the local 64bit architecture)</entry> + </row> + + <row> + <entry><constant>root-secondary-verity</constant></entry> + <entry>Verity data for the root file system partition of the secondary architecture</entry> + </row> + + <row> + <entry><constant>root-x86</constant></entry> + <entry>Root file system partition for the x86 (32bit, aka i386) architecture</entry> + </row> + + <row> + <entry><constant>root-x86-verity</constant></entry> + <entry>Verity data for the x86 (32bit) root file system partition</entry> + </row> + + <row> + <entry><constant>root-x86-64</constant></entry> + <entry>Root file system partition for the x86_64 (64bit, aka amd64) architecture</entry> + </row> + + <row> + <entry><constant>root-x86-64-verity</constant></entry> + <entry>Verity data for the x86_64 (64bit) root file system partition</entry> + </row> + + <row> + <entry><constant>root-arm</constant></entry> + <entry>Root file system partition for the ARM (32bit) architecture</entry> + </row> + + <row> + <entry><constant>root-arm-verity</constant></entry> + <entry>Verity data for the ARM (32bit) root file system partition</entry> + </row> + + <row> + <entry><constant>root-arm64</constant></entry> + <entry>Root file system partition for the ARM (64bit, aka aarch64) architecture</entry> + </row> + + <row> + <entry><constant>root-arm64-verity</constant></entry> + <entry>Verity data for the ARM (64bit, aka aarch64) root file system partition</entry> + </row> + + <row> + <entry><constant>root-ia64</constant></entry> + <entry>Root file system partition for the ia64 architecture</entry> + </row> + + <row> + <entry><constant>root-ia64-verity</constant></entry> + <entry>Verity data for the ia64 root file system partition</entry> + </row> + + <row> + <entry><constant>root-riscv32</constant></entry> + <entry>Root file system partition for the RISC-V 32-bit architecture</entry> + </row> + + <row> + <entry><constant>root-riscv32-verity</constant></entry> + <entry>Verity data for the RISC-V 32-bit root file system partition</entry> + </row> + + <row> + <entry><constant>root-riscv64</constant></entry> + <entry>Root file system partition for the RISC-V 64-bit architecture</entry> + </row> + + <row> + <entry><constant>root-riscv64-verity</constant></entry> + <entry>Verity data for the RISC-V 64-bit root file system partition</entry> + </row> + + <row> + <entry><constant>usr</constant></entry> + <entry><filename>/usr/</filename> file system partition type appropriate for the local architecture (an alias for an architecture <filename>/usr/</filename> file system partition type listed below, e.g. <constant>usr-x86-64</constant>)</entry> + </row> + + <row> + <entry><constant>usr-verity</constant></entry> + <entry>Verity data for the <filename>/usr/</filename> file system partition for the local architecture</entry> + </row> + + <row> + <entry><constant>usr-secondary</constant></entry> + <entry><filename>/usr/</filename> file system partition of the secondary architecture of the local architecture (usually the matching 32bit architecture for the local 64bit architecture)</entry> + </row> + + <row> + <entry><constant>usr-secondary-verity</constant></entry> + <entry>Verity data for the <filename>/usr/</filename> file system partition of the secondary architecture</entry> + </row> + + <row> + <entry><constant>usr-x86</constant></entry> + <entry><filename>/usr/</filename> file system partition for the x86 (32bit, aka i386) architecture</entry> + </row> + + <row> + <entry><constant>usr-x86-verity</constant></entry> + <entry>Verity data for the x86 (32bit) <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-x86-64</constant></entry> + <entry><filename>/usr/</filename> file system partition for the x86_64 (64bit, aka amd64) architecture</entry> + </row> + + <row> + <entry><constant>usr-x86-64-verity</constant></entry> + <entry>Verity data for the x86_64 (64bit) <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-arm</constant></entry> + <entry><filename>/usr/</filename> file system partition for the ARM (32bit) architecture</entry> + </row> + + <row> + <entry><constant>usr-arm-verity</constant></entry> + <entry>Verity data for the ARM (32bit) <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-arm64</constant></entry> + <entry><filename>/usr/</filename> file system partition for the ARM (64bit, aka aarch64) architecture</entry> + </row> + + <row> + <entry><constant>usr-arm64-verity</constant></entry> + <entry>Verity data for the ARM (64bit, aka aarch64) <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-ia64</constant></entry> + <entry><filename>/usr/</filename> file system partition for the ia64 architecture</entry> + </row> + + <row> + <entry><constant>usr-ia64-verity</constant></entry> + <entry>Verity data for the ia64 <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-riscv32</constant></entry> + <entry><filename>/usr/</filename> file system partition for the RISC-V 32-bit architecture</entry> + </row> + + <row> + <entry><constant>usr-riscv32-verity</constant></entry> + <entry>Verity data for the RISC-V 32-bit <filename>/usr/</filename> file system partition</entry> + </row> + + <row> + <entry><constant>usr-riscv64</constant></entry> + <entry><filename>/usr/</filename> file system partition for the RISC-V 64-bit architecture</entry> + </row> + + <row> + <entry><constant>usr-riscv64-verity</constant></entry> + <entry>Verity data for the RISC-V 64-bit <filename>/usr/</filename> file system partition</entry> + </row> + + + </tbody> + </tgroup> + </table> + + <para>This setting defaults to <constant>linux-generic</constant>.</para> + + <para>Most of the partition type UUIDs listed above are defined in the <ulink + url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable Partitions + Specification</ulink>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>Label=</varname></term> + + <listitem><para>The textual label to assign to the partition if none is assigned yet. Note that this + setting is not used for matching. It is also not used when a label is already set for an existing + partition. It is thus only used when a partition is newly created or when an existing one had a no + label set (that is: an empty label). If not specified a label derived from the partition type is + automatically used. Simple specifier expansion is supported, see below.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>UUID=</varname></term> + + <listitem><para>The UUID to assign to the partition if none is assigned yet. Note that this + setting is not used for matching. It is also not used when a UUID is already set for an existing + partition. It is thus only used when a partition is newly created or when an existing one had a + all-zero UUID set. If not specified a UUID derived from the partition type is automatically + used.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>Priority=</varname></term> + + <listitem><para>A numeric priority to assign to this partition, in the range -2147483648…2147483647, + with smaller values indicating higher priority, and higher values indicating smaller priority. This + priority is used in case the configured size constraints on the defined partitions do not permit + fitting all partitions onto the available disk space. If the partitions do not fit, the highest + numeric partition priority of all defined partitions is determined, and all defined partitions with + this priority are removed from the list of new partitions to create (which may be multiple, if the + same priority is used for multiple partitions). The fitting algorithm is then tried again. If the + partitions still do not fit, the now highest numeric partition priority is determined, and the + matching partitions removed too, and so on. Partitions of a priority of 0 or lower are never + removed. If all partitions with a priority above 0 are removed and the partitions still do not fit on + the device the operation fails. Note that this priority has no effect on ordering partitions, for + that use the alphabetical order of the filenames of the partition definition files. Defaults to + 0.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>Weight=</varname></term> + + <listitem><para>A numeric weight to assign to this partition in the range 0…1000000. Available disk + space is assigned the defined partitions according to their relative weights (subject to the size + constraints configured with <varname>SizeMinBytes=</varname>, <varname>SizeMaxBytes=</varname>), so + that a partition with weight 2000 gets double the space as one with weight 1000, and a partition with + weight 333 a third of that. Defaults to 1000.</para> + + <para>The <varname>Weight=</varname> setting is used to distribute available disk space in an + "elastic" fashion, based on the disk size and existing partitions. If a partition shall have a fixed + size use both <varname>SizeMinBytes=</varname> and <varname>SizeMaxBytes=</varname> with the same + value in order to fixate the size to one value, in which case the weight has no + effect.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>PaddingWeight=</varname></term> + + <listitem><para>Similar to <varname>Weight=</varname> but sets a weight for the free space after the + partition (the "padding"). When distributing available space the weights of all partitions and all + defined padding is summed, and then each partition and padding gets the fraction defined by its + weight. Defaults to 0, i.e. by default no padding is applied.</para> + + <para>Padding is useful if empty space shall be left for later additions or a safety margin at the + end of the device or between partitions.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>SizeMinBytes=</varname></term> + <term><varname>SizeMaxBytes=</varname></term> + + <listitem><para>Specifies minimum and maximum size constraints in bytes. Takes the usual K, M, G, T, + … suffixes (to the base of 1024). If <varname>SizeMinBytes=</varname> is specified the partition is + created at or grown to at least the specified size. If <varname>SizeMaxBytes=</varname> is specified + the partition is created at or grown to at most the specified size. The precise size is determined + through the weight value value configured with <varname>Weight=</varname>, see above. When + <varname>SizeMinBytes=</varname> is set equal to <varname>SizeMaxBytes=</varname> the configured + weight has no effect as the partition is explicitly sized to the specified fixed value. Note that + partitions are never created smaller than 4096 bytes, and since partitions are never shrunk the + previous size of the partition (in case the partition already exists) is also enforced as lower bound + for the new size. The values should be specified as multiples of 4096 bytes, and are rounded upwards + (in case of <varname>SizeMinBytes=</varname>) or downwards (in case of + <varname>SizeMaxBytes=</varname>) otherwise. If the backing device does not provide enough space to + fulfill the constraints placing the partition will fail. For partitions that shall be created, + depending on the setting of <varname>Priority=</varname> (see above) the partition might be dropped + and the placing algorithm restarted. By default a minimum size constraint of 10M and no maximum size + constraint is set.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>PaddingMinBytes=</varname></term> + <term><varname>PaddingMaxBytes=</varname></term> + + <listitem><para>Specifies minimum and maximum size constraints in bytes for the free space after the + partition (the "padding"). Semantics are similar to <varname>SizeMinBytes=</varname> and + <varname>SizeMaxBytes=</varname>, except that unlike partition sizes free space can be shrunk and can + be as small as zero. By default no size constraints on padding are set, so that only + <varname>PaddingWeight=</varname> determines the size of the padding applied.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>CopyBlocks=</varname></term> + + <listitem><para>Takes a path to a regular file, block device node or directory. If specified and the + partition is newly created the data from the specified path is written to the newly created + partition, on the block level. If a directory is specified the backing block device of the file + system the directory is on is determined and the data read directly from that. This option is useful + to efficiently replicate existing file systems on the block level on a new partition, for example to + build a simple OS installer or OS image builder.</para> + + <para>The file specified here must have a size that is a multiple of the basic block size 512 and not + be empty. If this option is used, the size allocation algorithm is slightly altered: the partition is + created as least as big as required to fit the data in, i.e. the data size is an additional minimum + size value taken into consideration for the allocation algorithm, similar to and in addition to the + <varname>SizeMin=</varname> value configured above.</para> + + <para>This option has no effect if the partition it is declared for already exists, i.e. existing + data is never overwritten. Note that the data is copied in before the partition table is updated, + i.e. before the partition actually is persistently created. This provides robustness: it is + guaranteed that the partition either doesn't exist or exists fully populated; it is not possible that + the partition exists but is not or only partially populated.</para> + + <para>This option cannot be combined with <varname>Format=</varname> or + <varname>CopyFiles=</varname>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>Format=</varname></term> + + <listitem><para>Takes a file system name, such as <literal>ext4</literal>, <literal>btrfs</literal>, + <literal>xfs</literal> or <literal>vfat</literal>, or the special value <literal>swap</literal>. If + specified and the partition is newly created it is formatted with the specified file system (or as + swap device). The file system UUID and label are automatically derived from the partition UUID and + label. If this option is used, the size allocation algorithm is slightly altered: the partition is + created as least as big as required for the minimal file system of the specified type (or 4KiB if the + minimal size is not known).</para> + + <para>This option has no effect if the partition already exists.</para> + + <para>Similar to the behaviour of <varname>CopyBlocks=</varname> the file system is formatted before + the partition is created, ensuring that the partition only ever exists with a fully initialized + file system.</para> + + <para>This option cannot be combined with <varname>CopyBlocks=</varname>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>CopyFiles=</varname></term> + + <listitem><para>Takes a pair of colon separated absolute file system paths. The first path refers to + a source file or directory on the host, the second path refers to a target in the file system of the + newly created partition and formatted file system. This setting may be used to copy files or + directories from the host into the file system that is created due to the <varname>Format=</varname> + option. If <varname>CopyFiles=</varname> is used without <varname>Format=</varname> specified + explicitly, <literal>Format=</literal> with a suitable default is implied (currently + <literal>ext4</literal>, but this may change in the future). This option may be used multiple times + to copy multiple files or directories from host into the newly formatted file system. The colon and + second path may be omitted in which case the source path is also used as the target path (relative to + the root of the newly created file system). If the source path refers to a directory it is copied + recursively.</para> + + <para>This option has no effect if the partition already exists: it cannot be used to copy additional + files into an existing partition, it may only be used to populate a file system created anew.</para> + + <para>The copy operation is executed before the file system is registered in the partition table, + thus ensuring that a file system populated this way only ever exists fully initialized.</para> + + <para>This option cannot be combined with <varname>CopyBlocks=</varname>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>Encrypt=</varname></term> + + <listitem><para>Takes a boolean parameter, defaulting to false. If true the partition will be + formatted with a LUKS2 superblock, before the blocks configured with <varname>CopyBlocks=</varname> + are copied in or the file system configured with <varname>Format=</varname> is created.</para> + + <para>The LUKS2 UUID is automatically derived from the partition UUID in a stable fashion. A single + key is added to the LUKS2 superblock, configurable with the <option>--key-file=</option> switch to + <command>systemd-repart</command>.</para> + + <para>When used this slightly alters the size allocation logic as the implicit, minimal size limits + of <varname>Format=</varname> and <varname>CopyBlocks=</varname> are increased by the space necessary + for the LUKS2 superblock (see above).</para> + + <para>This option has no effect if the partition already exists.</para></listitem> + </varlistentry> + + <varlistentry> + <term><varname>FactoryReset=</varname></term> + + <listitem><para>Takes a boolean argument. If specified the partition is marked for removal during a + factory reset operation. This functionality is useful to implement schemes where images can be reset + into their original state by removing partitions and creating them anew. Defaults to off.</para></listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Specifiers</title> + + <para>Specifiers may be used in the <varname>Label=</varname> setting. The following expansions are understood:</para> + <table class='specifiers'> + <title>Specifiers available</title> + <tgroup cols='3' align='left' colsep='1' rowsep='1'> + <colspec colname="spec" /> + <colspec colname="mean" /> + <colspec colname="detail" /> + <thead> + <row> + <entry>Specifier</entry> + <entry>Meaning</entry> + <entry>Details</entry> + </row> + </thead> + <tbody> + <xi:include href="standard-specifiers.xml" xpointer="a"/> + <xi:include href="standard-specifiers.xml" xpointer="b"/> + <xi:include href="standard-specifiers.xml" xpointer="B"/> + <xi:include href="standard-specifiers.xml" xpointer="H"/> + <xi:include href="standard-specifiers.xml" xpointer="l"/> + <xi:include href="standard-specifiers.xml" xpointer="m"/> + <xi:include href="standard-specifiers.xml" xpointer="o"/> + <xi:include href="standard-specifiers.xml" xpointer="v"/> + <xi:include href="standard-specifiers.xml" xpointer="w"/> + <xi:include href="standard-specifiers.xml" xpointer="W"/> + <xi:include href="standard-specifiers.xml" xpointer="percent"/> + </tbody> + </tgroup> + </table> + </refsect1> + + <refsect1> + <title>Examples</title> + + <example> + <title>Grow the root partition to the full disk size at first boot</title> + + <para>With the following file the root partition is automatically grown to the full disk if possible during boot.</para> + + <para><programlisting># /usr/lib/repart.d/50-root.conf +[Partition] +Type=root +</programlisting></para> + </example> + + <example> + <title>Create a swap and home partition automatically on boot, if missing</title> + + <para>The home partition gets all available disk space while the swap partition gets 1G at most and 64M + at least. We set a priority > 0 on the swap partition to ensure the swap partition is not used if not + enough space is available. For every three bytes assigned to the home partition the swap partition gets + assigned one.</para> + + <para><programlisting># /usr/lib/repart.d/60-home.conf +[Partition] +Type=home +</programlisting></para> + + <para><programlisting># /usr/lib/repart.d/70-swap.conf +[Partition] +Type=swap +SizeMinBytes=64M +SizeMaxBytes=1G +Priority=1 +Weight=333 +</programlisting></para> + </example> + + <example> + <title>Create B partitions in an A/B Verity setup, if missing</title> + + <para>Let's say the vendor intends to update OS images in an A/B setup, i.e. with two root partitions + (and two matching Verity partitions) that shall be used alternatingly during upgrades. To minimize + image sizes the original image is shipped only with one root and one Verity partition (the "A" set), + and the second root and Verity partitions (the "B" set) shall be created on first boot on the free + space on the medium.</para> + + <para><programlisting># /usr/lib/repart.d/50-root.conf +[Partition] +Type=root +SizeMinBytes=512M +SizeMaxBytes=512M +</programlisting></para> + + <para><programlisting># /usr/lib/repart.d/60-root-verity.conf +[Partition] +Type=root-verity +SizeMinBytes=64M +SizeMaxBytes=64M +</programlisting></para> + + <para>The definitions above cover the "A" set of root partition (of a fixed 512M size) and Verity + partition for the root partition (of a fixed 64M size). Let's use symlinks to create the "B" set of + partitions, since after all they shall have the same properties and sizes as the "A" set.</para> + +<para><programlisting># ln -s 50-root.conf /usr/lib/repart.d/70-root-b.conf +# ln -s 60-root-verity.conf /usr/lib/repart.d/80-root-verity-b.conf +</programlisting></para> + </example> + + </refsect1> + + <refsect1> + <title>See Also</title> + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-repart</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>sfdisk</refentrytitle><manvolnum>8</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |