1REPART.D(5) repart.d REPART.D(5)
2
6 repart.d - Partition Definition Files for Automatic Boot-Time
7 Repartitioning
8
10 /etc/repart.d/*.conf
11 /run/repart.d/*.conf
12 /usr/lib/repart.d/*.conf
13
16 repart.d/*.conf files describe basic properties of partitions of block
17 devices of the local system. They may be used to declare types, names
18 and sizes of partitions that shall exist. The systemd-repart(8) service
19 reads these files and attempts to add new partitions currently missing
20 and enlarge existing partitions according to these definitions.
21 Operation is generally incremental, i.e. when applied, what exists
22 already is left intact, and partitions are never shrunk, moved or
23 deleted.
24 These definition files are useful for implementing operating system
26 images that are prepared and delivered with minimally sized images (for
27 example lacking any state or swap partitions), and which on first boot
28 automatically take possession of any remaining disk space following a
29 few basic rules.
30 Currently, support for partition definition files is only implemented
32 for GPT partition tables.
33 Partition files are generally matched against any partitions already
35 existing on disk in a simple algorithm: the partition files are sorted
36 by their filename (ignoring the directory prefix), and then compared in
37 order against existing partitions matching the same partition type
38 UUID. Specifically, the first existing partition with a specific
39 partition type UUID is assigned the first definition file with the same
40 partition type UUID, and the second existing partition with a specific
41 type UUID the second partition file with the same type UUID, and so on.
42 Any left-over partition files that have no matching existing partition
43 are assumed to define new partition that shall be created. Such
44 partitions are appended to the end of the partition table, in the order
45 defined by their names utilizing the first partition slot greater than
46 the highest slot number currently in use. Any existing partitions that
47 have no matching partition file are left as they are.
48 Note that these definitions may only be used to create and initialize
50 new partitions or to grow existing ones. In the latter case it will not
51 grow the contained files systems however; separate mechanisms, such as
52 systemd-growfs(8) may be used to grow the file systems inside of these
53 partitions. Partitions may also be marked for automatic growing via the
54 GrowFileSystem= setting, in which case the file system is grown on
55 first mount by tools that respect this flag. See below for details.
56
58 Type=
59 The GPT partition type UUID to match. This may be a GPT partition
60 type UUID such as 4f68bce3-e8cd-4db1-96e7-fbcaf984b709, or an
61 identifier. Architecture specific partition types can use one of
62 these architecture identifiers: alpha, arc, arm (32-bit), arm64
63 (64-bit, aka aarch64), ia64, loongarch64, mips-le, mips64-le,
64 parisc, ppc, ppc64, ppc64-le, riscv32, riscv64, s390, s390x,
65 tilegx, x86 (32-bit, aka i386) and x86-64 (64-bit, aka amd64). The
66 supported identifiers are:
67 Table 1. GPT partition type identifiers
69 ┌──────────────────────────┬────────────────────────────┐
70 │Identifier │ Explanation │
71 ├──────────────────────────┼────────────────────────────┤
72 │esp │ EFI System Partition │
73 ├──────────────────────────┼────────────────────────────┤
74 │xbootldr │ Extended Boot Loader │
75 │ │ Partition │
76 ├──────────────────────────┼────────────────────────────┤
77 │swap │ Swap partition │
78 ├──────────────────────────┼────────────────────────────┤
79 │home │ Home (/home/) partition │
80 ├──────────────────────────┼────────────────────────────┤
81 │srv │ Server data (/srv/) │
82 │ │ partition │
83 ├──────────────────────────┼────────────────────────────┤
84 │var │ Variable data (/var/) │
85 │ │ partition │
86 ├──────────────────────────┼────────────────────────────┤
87 │tmp │ Temporary data (/var/tmp/) │
88 │ │ partition │
89 ├──────────────────────────┼────────────────────────────┤
90 │linux-generic │ Generic Linux file system │
91 │ │ partition │
92 ├──────────────────────────┼────────────────────────────┤
93 │root │ Root file system partition │
94 │ │ type appropriate for the │
95 │ │ local architecture (an │
96 │ │ alias for an architecture │
97 │ │ root file system partition │
98 │ │ type listed below, e.g. │
99 │ │ root-x86-64) │
100 ├──────────────────────────┼────────────────────────────┤
101 │root-verity │ Verity data for the root │
102 │ │ file system partition for │
103 │ │ the local architecture │
104 ├──────────────────────────┼────────────────────────────┤
105 │root-verity-sig │ Verity signature data for │
106 │ │ the root file system │
107 │ │ partition for the local │
108 │ │ architecture │
109 ├──────────────────────────┼────────────────────────────┤
110 │root-secondary │ Root file system partition │
111 │ │ of the secondary │
112 │ │ architecture of the local │
113 │ │ architecture (usually the │
114 │ │ matching 32-bit │
115 │ │ architecture for the local │
116 │ │ 64-bit architecture) │
117 ├──────────────────────────┼────────────────────────────┤
118 │root-secondary-verity │ Verity data for the root │
119 │ │ file system partition of │
120 │ │ the secondary architecture │
121 ├──────────────────────────┼────────────────────────────┤
122 │root-secondary-verity-sig │ Verity signature data for │
123 │ │ the root file system │
124 │ │ partition of the secondary │
125 │ │ architecture │
126 ├──────────────────────────┼────────────────────────────┤
127 │root-{arch} │ Root file system partition │
128 │ │ of the given architecture │
129 │ │ (such as root-x86-64 or │
130 │ │ root-riscv64) │
131 ├──────────────────────────┼────────────────────────────┤
132 │root-{arch}-verity │ Verity data for the root │
133 │ │ file system partition of │
134 │ │ the given architecture │
135 ├──────────────────────────┼────────────────────────────┤
136 │root-{arch}-verity-sig │ Verity signature data for │
137 │ │ the root file system │
138 │ │ partition of the given │
139 │ │ architecture │
140 ├──────────────────────────┼────────────────────────────┤
141 │usr │ /usr/ file system │
142 │ │ partition type appropriate │
143 │ │ for the local architecture │
144 │ │ (an alias for an │
145 │ │ architecture /usr/ file │
146 │ │ system partition type │
147 │ │ listed below, e.g. │
148 │ │ usr-x86-64) │
149 ├──────────────────────────┼────────────────────────────┤
150 │usr-verity │ Verity data for the /usr/ │
151 │ │ file system partition for │
152 │ │ the local architecture │
153 ├──────────────────────────┼────────────────────────────┤
154 │usr-verity-sig │ Verity signature data for │
155 │ │ the /usr/ file system │
156 │ │ partition for the local │
157 │ │ architecture │
158 ├──────────────────────────┼────────────────────────────┤
159 │usr-secondary │ /usr/ file system │
160 │ │ partition of the secondary │
161 │ │ architecture of the local │
162 │ │ architecture (usually the │
163 │ │ matching 32-bit │
164 │ │ architecture for the local │
165 │ │ 64-bit architecture) │
166 ├──────────────────────────┼────────────────────────────┤
167 │usr-secondary-verity │ Verity data for the /usr/ │
168 │ │ file system partition of │
169 │ │ the secondary architecture │
170 ├──────────────────────────┼────────────────────────────┤
171 │usr-secondary-verity-sig │ Verity signature data for │
172 │ │ the /usr/ file system │
173 │ │ partition of the secondary │
174 │ │ architecture │
175 ├──────────────────────────┼────────────────────────────┤
176 │usr-{arch} │ /usr/ file system │
177 │ │ partition of the given │
178 │ │ architecture │
179 ├──────────────────────────┼────────────────────────────┤
180 │usr-{arch}-verity │ Verity data for the /usr/ │
181 │ │ file system partition of │
182 │ │ the given architecture │
183 ├──────────────────────────┼────────────────────────────┤
184 │usr-{arch}-verity-sig │ Verity signature data for │
185 │ │ the /usr/ file system │
186 │ │ partition of the given │
187 │ │ architecture │
188 └──────────────────────────┴────────────────────────────┘
189 This setting defaults to linux-generic.
190 Most of the partition type UUIDs listed above are defined in the
192 Discoverable Partitions Specification[1].
193 Label=
195 The textual label to assign to the partition if none is assigned
196 yet. Note that this setting is not used for matching. It is also
197 not used when a label is already set for an existing partition. It
198 is thus only used when a partition is newly created or when an
199 existing one had a no label set (that is: an empty label). If not
200 specified a label derived from the partition type is automatically
201 used. Simple specifier expansion is supported, see below.
202 UUID=
204 The UUID to assign to the partition if none is assigned yet. Note
205 that this setting is not used for matching. It is also not used
206 when a UUID is already set for an existing partition. It is thus
207 only used when a partition is newly created or when an existing one
208 had a all-zero UUID set. If set to "null", the UUID is set to all
209 zeroes. If not specified a UUID derived from the partition type is
210 automatically used.
211 Priority=
213 A numeric priority to assign to this partition, in the range
214 -2147483648...2147483647, with smaller values indicating higher
215 priority, and higher values indicating smaller priority. This
216 priority is used in case the configured size constraints on the
217 defined partitions do not permit fitting all partitions onto the
218 available disk space. If the partitions do not fit, the highest
219 numeric partition priority of all defined partitions is determined,
220 and all defined partitions with this priority are removed from the
221 list of new partitions to create (which may be multiple, if the
222 same priority is used for multiple partitions). The fitting
223 algorithm is then tried again. If the partitions still do not fit,
224 the now highest numeric partition priority is determined, and the
225 matching partitions removed too, and so on. Partitions of a
226 priority of 0 or lower are never removed. If all partitions with a
227 priority above 0 are removed and the partitions still do not fit on
228 the device the operation fails. Note that this priority has no
229 effect on ordering partitions, for that use the alphabetical order
230 of the filenames of the partition definition files. Defaults to 0.
231 Weight=
233 A numeric weight to assign to this partition in the range
234 0...1000000. Available disk space is assigned the defined
235 partitions according to their relative weights (subject to the size
236 constraints configured with SizeMinBytes=, SizeMaxBytes=), so that
237 a partition with weight 2000 gets double the space as one with
238 weight 1000, and a partition with weight 333 a third of that.
239 Defaults to 1000.
240 The Weight= setting is used to distribute available disk space in
242 an "elastic" fashion, based on the disk size and existing
243 partitions. If a partition shall have a fixed size use both
244 SizeMinBytes= and SizeMaxBytes= with the same value in order to
245 fixate the size to one value, in which case the weight has no
246 effect.
247 PaddingWeight=
249 Similar to Weight=, but sets a weight for the free space after the
250 partition (the "padding"). When distributing available space the
251 weights of all partitions and all defined padding is summed, and
252 then each partition and padding gets the fraction defined by its
253 weight. Defaults to 0, i.e. by default no padding is applied.
254 Padding is useful if empty space shall be left for later additions
256 or a safety margin at the end of the device or between partitions.
257 SizeMinBytes=, SizeMaxBytes=
259 Specifies minimum and maximum size constraints in bytes. Takes the
260 usual K, M, G, T, ... suffixes (to the base of 1024). If
261 SizeMinBytes= is specified the partition is created at or grown to
262 at least the specified size. If SizeMaxBytes= is specified the
263 partition is created at or grown to at most the specified size. The
264 precise size is determined through the weight value configured with
265 Weight=, see above. When SizeMinBytes= is set equal to
266 SizeMaxBytes= the configured weight has no effect as the partition
267 is explicitly sized to the specified fixed value. Note that
268 partitions are never created smaller than 4096 bytes, and since
269 partitions are never shrunk the previous size of the partition (in
270 case the partition already exists) is also enforced as lower bound
271 for the new size. The values should be specified as multiples of
272 4096 bytes, and are rounded upwards (in case of SizeMinBytes=) or
273 downwards (in case of SizeMaxBytes=) otherwise. If the backing
274 device does not provide enough space to fulfill the constraints
275 placing the partition will fail. For partitions that shall be
276 created, depending on the setting of Priority= (see above) the
277 partition might be dropped and the placing algorithm restarted. By
278 default a minimum size constraint of 10M and no maximum size
279 constraint is set.
280 PaddingMinBytes=, PaddingMaxBytes=
282 Specifies minimum and maximum size constraints in bytes for the
283 free space after the partition (the "padding"). Semantics are
284 similar to SizeMinBytes= and SizeMaxBytes=, except that unlike
285 partition sizes free space can be shrunk and can be as small as
286 zero. By default no size constraints on padding are set, so that
287 only PaddingWeight= determines the size of the padding applied.
288 CopyBlocks=
290 Takes a path to a regular file, block device node or directory, or
291 the special value "auto". If specified and the partition is newly
292 created, the data from the specified path is written to the newly
293 created partition, on the block level. If a directory is specified,
294 the backing block device of the file system the directory is on is
295 determined, and the data read directly from that. This option is
296 useful to efficiently replicate existing file systems onto new
297 partitions on the block level — for example to build a simple OS
298 installer or an OS image builder.
299 If the special value "auto" is specified, the source to copy from
301 is automatically picked up from the running system (or the image
302 specified with --image= — if used). A partition that matches both
303 the configured partition type (as declared with Type= described
304 above), and the currently mounted directory appropriate for that
305 partition type is determined. For example, if the partition type is
306 set to "root" the partition backing the root directory (/) is used
307 as source to copy from — if its partition type is set to "root" as
308 well. If the declared type is "usr" the partition backing /usr/ is
309 used as source to copy blocks from — if its partition type is set
310 to "usr" too. The logic is capable of automatically tracking down
311 the backing partitions for encrypted and Verity-enabled volumes.
312 "CopyBlocks=auto" is useful for implementing "self-replicating"
313 systems, i.e. systems that are their own installer.
314 The file specified here must have a size that is a multiple of the
316 basic block size 512 and not be empty. If this option is used, the
317 size allocation algorithm is slightly altered: the partition is
318 created as least as big as required to fit the data in, i.e. the
319 data size is an additional minimum size value taken into
320 consideration for the allocation algorithm, similar to and in
321 addition to the SizeMin= value configured above.
322 This option has no effect if the partition it is declared for
324 already exists, i.e. existing data is never overwritten. Note that
325 the data is copied in before the partition table is updated, i.e.
326 before the partition actually is persistently created. This
327 provides robustness: it is guaranteed that the partition either
328 doesn't exist or exists fully populated; it is not possible that
329 the partition exists but is not or only partially populated.
330 This option cannot be combined with Format= or CopyFiles=.
332 Format=
334 Takes a file system name, such as "ext4", "btrfs", "xfs", "vfat",
335 "erofs", "squashfs" or the special value "swap". If specified and
336 the partition is newly created it is formatted with the specified
337 file system (or as swap device). The file system UUID and label are
338 automatically derived from the partition UUID and label. If this
339 option is used, the size allocation algorithm is slightly altered:
340 the partition is created as least as big as required for the
341 minimal file system of the specified type (or 4KiB if the minimal
342 size is not known).
343 This option has no effect if the partition already exists.
345 Similarly to the behaviour of CopyBlocks=, the file system is
347 formatted before the partition is created, ensuring that the
348 partition only ever exists with a fully initialized file system.
349 This option cannot be combined with CopyBlocks=.
351 CopyFiles=
353 Takes a pair of colon separated absolute file system paths. The
354 first path refers to a source file or directory on the host, the
355 second path refers to a target in the file system of the newly
356 created partition and formatted file system. This setting may be
357 used to copy files or directories from the host into the file
358 system that is created due to the Format= option. If CopyFiles= is
359 used without Format= specified explicitly, "Format=" with a
360 suitable default is implied (currently "vfat" for "ESP" and
361 "XBOOTLDR" partitions, and "ext4" otherwise, but this may change in
362 the future). This option may be used multiple times to copy
363 multiple files or directories from host into the newly formatted
364 file system. The colon and second path may be omitted in which case
365 the source path is also used as the target path (relative to the
366 root of the newly created file system). If the source path refers
367 to a directory it is copied recursively.
368 This option has no effect if the partition already exists: it
370 cannot be used to copy additional files into an existing partition,
371 it may only be used to populate a file system created anew.
372 The copy operation is executed before the file system is registered
374 in the partition table, thus ensuring that a file system populated
375 this way only ever exists fully initialized.
376 Note that CopyFiles= will skip copying files that aren't supported
378 by the target filesystem (e.g symlinks, fifos, sockets and devices
379 on vfat). When an unsupported file type is encountered,
380 systemd-repart will skip copying this file and write a log message
381 about it.
382 Note that systemd-repart does not change the UIDs/GIDs of any
384 copied files and directories. When running systemd-repart as an
385 unprivileged user to build an image of files and directories owned
386 by the same user, you can run systemd-repart in a user namespace
387 with the current user mapped to the root user to make sure the
388 files and directories in the image are owned by the root user.
389 Note that when populating XFS filesystems with systemd-repart and
391 loop devices are not available, populating XFS filesystems with
392 files containing spaces, tabs or newlines might fail on old
393 versions of mkfs.xfs(8) due to limitations of its protofile format.
394 Note that when populating XFS filesystems with systemd-repart and
396 loop devices are not available, extended attributes will not be
397 copied into generated XFS filesystems due to limitations
398 mkfs.xfs(8)'s protofile format.
399 This option cannot be combined with CopyBlocks=.
401 When systemd-repart(8) is invoked with the --image= or --root=
403 command line switches the source paths specified are taken relative
404 to the specified root directory or disk image root.
405 ExcludeFiles=, ExcludeFilesTarget=
407 Takes an absolute file system path referring to a source file or
408 directory on the host. This setting may be used to exclude files or
409 directories from the host from being copied into the file system
410 when CopyFiles= is used. This option may be used multiple times to
411 exclude multiple files or directories from host from being copied
412 into the newly formatted file system.
413 If the path is a directory and ends with "/", only the directory's
415 contents are excluded but not the directory itself. If the path is
416 a directory and does not end with "/", both the directory and its
417 contents are excluded.
418 ExcludeFilesTarget= is like ExcludeFiles= except that instead of
420 excluding the path on the host from being copied into the
421 partition, we exclude any files and directories from being copied
422 into the given path in the partition.
423 When systemd-repart(8) is invoked with the --image= or --root=
425 command line switches the paths specified are taken relative to the
426 specified root directory or disk image root.
427 MakeDirectories=
429 Takes one or more absolute paths, separated by whitespace, each
430 declaring a directory to create within the new file system.
431 Behaviour is similar to CopyFiles=, but instead of copying in a set
432 of files this just creates the specified directories with the
433 default mode of 0755 owned by the root user and group, plus all
434 their parent directories (with the same ownership and access mode).
435 To configure directories with different ownership or access mode,
436 use CopyFiles= and specify a source tree to copy containing
437 appropriately owned/configured directories. This option may be used
438 more than once to create multiple directories. When CopyFiles= and
439 MakeDirectories= are used together the former is applied first. If
440 a directory listed already exists no operation is executed (in
441 particular, the ownership/access mode of the directories is left as
442 is).
443 The primary use case for this option is to create a minimal set of
445 directories that may be mounted over by other partitions contained
446 in the same disk image. For example, a disk image where the root
447 file system is formatted at first boot might want to automatically
448 pre-create /usr/ in it this way, so that the "usr" partition may
449 over-mount it.
450 Consider using systemd-tmpfiles(8) with its --image= option to
452 pre-create other, more complex directory hierarchies (as well as
453 other inodes) with fine-grained control of ownership, access modes
454 and other file attributes.
455 Encrypt=
457 Takes one of "off", "key-file", "tpm2" and "key-file+tpm2"
458 (alternatively, also accepts a boolean value, which is mapped to
459 "off" when false, and "key-file" when true). Defaults to "off". If
460 not "off" the partition will be formatted with a LUKS2 superblock,
461 before the blocks configured with CopyBlocks= are copied in or the
462 file system configured with Format= is created.
463 The LUKS2 UUID is automatically derived from the partition UUID in
465 a stable fashion. If "key-file" or "key-file+tpm2" is used, a key
466 is added to the LUKS2 superblock, configurable with the --key-file=
467 option to systemd-repart. If "tpm2" or "key-file+tpm2" is used, a
468 key is added to the LUKS2 superblock that is enrolled to the local
469 TPM2 chip, as configured with the --tpm2-device= and --tpm2-pcrs=
470 options to systemd-repart.
471 When used this slightly alters the size allocation logic as the
473 implicit, minimal size limits of Format= and CopyBlocks= are
474 increased by the space necessary for the LUKS2 superblock (see
475 above).
476 This option has no effect if the partition already exists.
478 Verity=
480 Takes one of "off", "data", "hash" or "signature". Defaults to
481 "off". If set to "off" or "data", the partition is populated with
482 content as specified by CopyBlocks= or CopyFiles=. If set to
483 "hash", the partition will be populated with verity hashes from the
484 matching verity data partition. If set to "signature", the
485 partition will be populated with a JSON object containing a
486 signature of the verity root hash of the matching verity hash
487 partition.
488 A matching verity partition is a partition with the same verity
490 match key (as configured with VerityMatchKey=).
491 If not explicitly configured, the data partition's UUID will be set
493 to the first 128 bits of the verity root hash. Similarly, if not
494 configured, the hash partition's UUID will be set to the final 128
495 bits of the verity root hash. The verity root hash itself will be
496 included in the output of systemd-repart.
497 This option has no effect if the partition already exists.
499 Usage of this option in combination with Encrypt= is not supported.
501 For each unique VerityMatchKey= value, a single verity data
503 partition ("Verity=data") and a single verity hash partition
504 ("Verity=hash") must be defined.
505 VerityMatchKey=
507 Takes a short, user-chosen identifier string. This setting is used
508 to find sibling verity partitions for the current verity partition.
509 See the description for Verity=.
510 FactoryReset=
512 Takes a boolean argument. If specified the partition is marked for
513 removal during a factory reset operation. This functionality is
514 useful to implement schemes where images can be reset into their
515 original state by removing partitions and creating them anew.
516 Defaults to off.
517 Flags=
519 Configures the 64-bit GPT partition flags field to set for the
520 partition when creating it. This option has no effect if the
521 partition already exists. If not specified the flags values is set
522 to all zeroes, except for the three bits that can also be
523 configured via NoAuto=, ReadOnly= and GrowFileSystem=; see below
524 for details on the defaults for these three flags. Specify the
525 flags value in hexadecimal (by prefixing it with "0x"), binary
526 (prefix "0b") or decimal (no prefix).
527 NoAuto=, ReadOnly=, GrowFileSystem=
529 Configures the No-Auto, Read-Only and Grow-File-System partition
530 flags (bit 63, 60 and 59) of the partition table entry, as defined
531 by the Discoverable Partitions Specification[1]. Only available for
532 partition types supported by the specification. This option is a
533 friendly way to set bits 63, 60 and 59 of the partition flags value
534 without setting any of the other bits, and may be set via Flags=
535 too, see above.
536 If Flags= is used in conjunction with one or more of
538 NoAuto=/ReadOnly=/GrowFileSystem= the latter control the value of
539 the relevant flags, i.e. the high-level settings
540 NoAuto=/ReadOnly=/GrowFileSystem= override the relevant bits of the
541 low-level setting Flags=.
542 Note that the three flags affect only automatic partition mounting,
544 as implemented by systemd-gpt-auto-generator(8) or the --image=
545 option of various commands (such as systemd-nspawn(1)). It has no
546 effect on explicit mounts, such as those done via mount(8) or
547 fstab(5).
548 If both bit 50 and 59 are set for a partition (i.e. the partition
550 is marked both read-only and marked for file system growing) the
551 latter is typically without effect: the read-only flag takes
552 precedence in most tools reading these flags, and since growing the
553 file system involves writing to the partition it is consequently
554 ignored.
555 NoAuto= defaults to off. ReadOnly= defaults to on for Verity
557 partition types, and off for all others. GrowFileSystem= defaults
558 to on for all partition types that support it, except if the
559 partition is marked read-only (and thus effectively, defaults to
560 off for Verity partitions).
561 SplitName=
563 Configures the suffix to append to split artifacts when the --split
564 option of systemd-repart(8) is used. Simple specifier expansion is
565 supported, see below. Defaults to "%t". To disable split artifact
566 generation for a partition, set SplitName= to "-".
567 Minimize=
569 Takes one of "off", "best", and "guess" (alternatively, also
570 accepts a boolean value, which is mapped to "off" when false, and
571 "best" when true). Defaults to "off". If set to "best", the
572 partition will have the minimal size required to store the sources
573 configured with CopyFiles=. "best" is currently only supported for
574 read-only filesystems. If set to "guess", the partition is created
575 at least as big as required to store the sources configured with
576 CopyFiles=. Note that unless the filesystem is a read-only
577 filesystem, systemd-repart will have to populate the filesystem
578 twice to guess the minimal required size, so enabling this option
579 might slow down repart when populating large partitions.
580
582 Specifiers may be used in the Label=, CopyBlocks=, CopyFiles=,
583 MakeDirectories=, SplitName= settings. The following expansions are
584 understood:
585 Table 2. Specifiers available
587 ┌──────────┬─────────────────────┬────────────────────────┐
588 │Specifier │ Meaning │ Details │
589 ├──────────┼─────────────────────┼────────────────────────┤
590 │"%a" │ Architecture │ A short string │
591 │ │ │ identifying the │
592 │ │ │ architecture of the │
593 │ │ │ local system. A │
594 │ │ │ string such as x86, │
595 │ │ │ x86-64 or arm64. │
596 │ │ │ See the │
597 │ │ │ architectures │
598 │ │ │ defined for │
599 │ │ │ ConditionArchitecture= │
600 │ │ │ in systemd.unit(5) │
601 │ │ │ for a full list. │
602 ├──────────┼─────────────────────┼────────────────────────┤
603 │"%A" │ Operating system │ The operating system │
604 │ │ image version │ image version │
605 │ │ │ identifier of the │
606 │ │ │ running system, as │
607 │ │ │ read from the │
608 │ │ │ IMAGE_VERSION= field │
609 │ │ │ of /etc/os-release. If │
610 │ │ │ not set, resolves to │
611 │ │ │ an empty string. See │
612 │ │ │ os-release(5) for more │
613 │ │ │ information. │
614 ├──────────┼─────────────────────┼────────────────────────┤
615 │"%b" │ Boot ID │ The boot ID of the │
616 │ │ │ running system, │
617 │ │ │ formatted as string. │
618 │ │ │ See random(4) for more │
619 │ │ │ information. │
620 ├──────────┼─────────────────────┼────────────────────────┤
621 │"%B" │ Operating system │ The operating system │
622 │ │ build ID │ build identifier of │
623 │ │ │ the running system, as │
624 │ │ │ read from the │
625 │ │ │ BUILD_ID= field of │
626 │ │ │ /etc/os-release. If │
627 │ │ │ not set, resolves to │
628 │ │ │ an empty string. See │
629 │ │ │ os-release(5) for more │
630 │ │ │ information. │
631 ├──────────┼─────────────────────┼────────────────────────┤
632 │"%H" │ Host name │ The hostname of the │
633 │ │ │ running system. │
634 ├──────────┼─────────────────────┼────────────────────────┤
635 │"%l" │ Short host name │ The hostname of the │
636 │ │ │ running system, │
637 │ │ │ truncated at the first │
638 │ │ │ dot to remove any │
639 │ │ │ domain component. │
640 ├──────────┼─────────────────────┼────────────────────────┤
641 │"%m" │ Machine ID │ The machine ID of the │
642 │ │ │ running system, │
643 │ │ │ formatted as string. │
644 │ │ │ See machine-id(5) for │
645 │ │ │ more information. │
646 ├──────────┼─────────────────────┼────────────────────────┤
647 │"%M" │ Operating system │ The operating system │
648 │ │ image identifier │ image identifier of │
649 │ │ │ the running system, as │
650 │ │ │ read from the │
651 │ │ │ IMAGE_ID= field of │
652 │ │ │ /etc/os-release. If │
653 │ │ │ not set, resolves to │
654 │ │ │ an empty string. See │
655 │ │ │ os-release(5) for more │
656 │ │ │ information. │
657 ├──────────┼─────────────────────┼────────────────────────┤
658 │"%o" │ Operating system ID │ The operating system │
659 │ │ │ identifier of the │
660 │ │ │ running system, as │
661 │ │ │ read from the ID= │
662 │ │ │ field of │
663 │ │ │ /etc/os-release. See │
664 │ │ │ os-release(5) for more │
665 │ │ │ information. │
666 ├──────────┼─────────────────────┼────────────────────────┤
667 │"%v" │ Kernel release │ Identical to uname -r │
668 │ │ │ output. │
669 ├──────────┼─────────────────────┼────────────────────────┤
670 │"%w" │ Operating system │ The operating system │
671 │ │ version ID │ version identifier of │
672 │ │ │ the running system, as │
673 │ │ │ read from the │
674 │ │ │ VERSION_ID= field of │
675 │ │ │ /etc/os-release. If │
676 │ │ │ not set, resolves to │
677 │ │ │ an empty string. See │
678 │ │ │ os-release(5) for more │
679 │ │ │ information. │
680 ├──────────┼─────────────────────┼────────────────────────┤
681 │"%W" │ Operating system │ The operating system │
682 │ │ variant ID │ variant identifier of │
683 │ │ │ the running system, as │
684 │ │ │ read from the │
685 │ │ │ VARIANT_ID= field of │
686 │ │ │ /etc/os-release. If │
687 │ │ │ not set, resolves to │
688 │ │ │ an empty string. See │
689 │ │ │ os-release(5) for more │
690 │ │ │ information. │
691 ├──────────┼─────────────────────┼────────────────────────┤
692 │"%T" │ Directory for │ This is either /tmp or │
693 │ │ temporary files │ the path "$TMPDIR", │
694 │ │ │ "$TEMP" or "$TMP" are │
695 │ │ │ set to. (Note that the │
696 │ │ │ directory may be │
697 │ │ │ specified without a │
698 │ │ │ trailing slash.) │
699 ├──────────┼─────────────────────┼────────────────────────┤
700 │"%V" │ Directory for │ This is either │
701 │ │ larger and │ /var/tmp or the path │
702 │ │ persistent │ "$TMPDIR", "$TEMP" or │
703 │ │ temporary files │ "$TMP" are set to. │
704 │ │ │ (Note that the │
705 │ │ │ directory may be │
706 │ │ │ specified without a │
707 │ │ │ trailing slash.) │
708 ├──────────┼─────────────────────┼────────────────────────┤
709 │"%%" │ Single percent sign │ Use "%%" in place of │
710 │ │ │ "%" to specify a │
711 │ │ │ single percent sign. │
712 └──────────┴─────────────────────┴────────────────────────┘
713 Additionally, for the SplitName= setting, the following specifiers are
715 also understood:
716 Table 3. Specifiers available
718 ┌──────────┬─────────────────────┬─────────────────────┐
719 │Specifier │ Meaning │ Details │
720 ├──────────┼─────────────────────┼─────────────────────┤
721 │"%T" │ Partition Type UUID │ The partition type │
722 │ │ │ UUID, as configured │
723 │ │ │ with Type= │
724 ├──────────┼─────────────────────┼─────────────────────┤
725 │"%t" │ Partition Type │ The partition type │
726 │ │ Identifier │ identifier │
727 │ │ │ corresponding to │
728 │ │ │ the partition type │
729 │ │ │ UUID │
730 ├──────────┼─────────────────────┼─────────────────────┤
731 │"%U" │ Partition UUID │ The partition UUID, │
732 │ │ │ as configured with │
733 │ │ │ UUID= │
734 ├──────────┼─────────────────────┼─────────────────────┤
735 │"%n" │ Partition Number │ The partition │
736 │ │ │ number assigned to │
737 │ │ │ the partition │
738 └──────────┴─────────────────────┴─────────────────────┘
739
741 Example 1. Grow the root partition to the full disk size at first boot
742 With the following file the root partition is automatically grown to
744 the full disk if possible during boot.
745 # /usr/lib/repart.d/50-root.conf
747 [Partition]
748 Type=root
749 Example 2. Create a swap and home partition automatically on boot, if
752 missing
753 The home partition gets all available disk space while the swap
755 partition gets 1G at most and 64M at least. We set a priority > 0 on
756 the swap partition to ensure the swap partition is not used if not
757 enough space is available. For every three bytes assigned to the home
758 partition the swap partition gets assigned one.
759 # /usr/lib/repart.d/60-home.conf
761 [Partition]
762 Type=home
763 # /usr/lib/repart.d/70-swap.conf
765 [Partition]
766 Type=swap
767 SizeMinBytes=64M
768 SizeMaxBytes=1G
769 Priority=1
770 Weight=333
771 Example 3. Create B partitions in an A/B Verity setup, if missing
774 Let's say the vendor intends to update OS images in an A/B setup, i.e.
776 with two root partitions (and two matching Verity partitions) that
777 shall be used alternatingly during upgrades. To minimize image sizes
778 the original image is shipped only with one root and one Verity
779 partition (the "A" set), and the second root and Verity partitions (the
780 "B" set) shall be created on first boot on the free space on the
781 medium.
782 # /usr/lib/repart.d/50-root.conf
784 [Partition]
785 Type=root
786 SizeMinBytes=512M
787 SizeMaxBytes=512M
788 # /usr/lib/repart.d/60-root-verity.conf
790 [Partition]
791 Type=root-verity
792 SizeMinBytes=64M
793 SizeMaxBytes=64M
794 The definitions above cover the "A" set of root partition (of a fixed
796 512M size) and Verity partition for the root partition (of a fixed 64M
797 size). Let's use symlinks to create the "B" set of partitions, since
798 after all they shall have the same properties and sizes as the "A" set.
799 # ln -s 50-root.conf /usr/lib/repart.d/70-root-b.conf
801 # ln -s 60-root-verity.conf /usr/lib/repart.d/80-root-verity-b.conf
802 Example 4. Create a data and verity partition from a OS tree
805 Assuming we have an OS tree at /var/tmp/os-tree that we want to package
807 in a root partition together with a matching verity partition, we can
808 do so as follows:
809 # 50-root.conf
811 [Partition]
812 Type=root
813 CopyFiles=/var/tmp/os-tree
814 Verity=data
815 VerityMatchKey=root
816 # 60-root-verity.conf
818 [Partition]
819 Type=root-verity
820 Verity=hash
821 VerityMatchKey=root
822
825 systemd(1), systemd-repart(8), sfdisk(8), systemd-cryptenroll(1)
826
828 1. Discoverable Partitions Specification
829 https://uapi-group.org/specifications/specs/discoverable_partitions_specification
830systemd 254 REPART.D(5)