1HOMECTL(1) homectl HOMECTL(1)
2
6 homectl - Create, remove, change or inspect home directories
7
9 homectl [OPTIONS...] {COMMAND} [NAME...]
10
12 homectl may be used to create, remove, change or inspect a user's home
13 directory. It's primarily a command interfacing with systemd-
14 homed.service(8) which manages home directories of users.
15 Home directories managed by systemd-homed.service are self-contained,
17 and thus include the user's full metadata record in the home's data
18 storage itself, making them easy to migrate between machines. In
19 particular, a home directory describes a matching user record, and
20 every user record managed by systemd-homed.service also implies
21 existence and encapsulation of a home directory. The user account and
22 home directory become the same concept.
23 The following backing storage mechanisms are supported:
25 • An individual LUKS2 encrypted loopback file for a user, stored in
27 /home/*.home. At login the file system contained in this files is
28 mounted, after the LUKS2 encrypted volume has been attached. The
29 user's password is identical to the encryption passphrase of the
30 LUKS2 volume. Access to data without preceding user authentication
31 is thus not possible, even for the system administrator. This
32 storage mechanism provides the strongest data security and is thus
33 recommended.
34 • Similar, but the LUKS2 encrypted file system is located on regular
36 block device, such as an USB storage stick. In this mode home
37 directories and all data they include are nicely migratable between
38 machines, simply by plugging the USB stick into different systems
39 at different times.
40 • An encrypted directory using "fscrypt" on file systems that support
42 it (at the moment this is primarily "ext4"), located in
43 /home/*.homedir. This mechanism also provides encryption, but
44 substantially weaker than LUKS2, as most file system metadata is
45 unprotected. Moreover it currently does not support changing user
46 passwords once the home directory has been created.
47 • A "btrfs" subvolume for each user, also located in /home/*.homedir.
49 This provides no encryption, but good quota support.
50 • A regular directory for each user, also located in /home/*.homedir.
52 This provides no encryption, but is a suitable fallback available
53 on all machines, even where LUKS2, "fscrypt" or "btrfs" support is
54 not available.
55 • An individual Windows file share (CIFS) for each user.
57 Note that systemd-homed.service and homectl will not manage "classic"
59 UNIX user accounts as created with useradd(8) or similar tools. In
60 particular, this functionality is not suitable for managing system
61 users (i.e. users with a UID below 1000) but is exclusive to regular
62 ("human") users.
63 Note that users/home directories managed via systemd-homed.service do
65 not show up in /etc/passwd and similar files, they are synthesized via
66 glibc NSS during runtime. They are thus resolvable and may be
67 enumerated via the getent(1) tool.
68 This tool interfaces directly with systemd-homed.service, and may
70 execute specific commands on the home directories it manages. Since
71 every home directory managed that way also defines a JSON user and
72 group record these home directories may also be inspected and
73 enumerated via userdbctl(1).
74 Home directories managed by systemd-homed.service are usually in one of
76 two states, or in a transition state between them: when "active" they
77 are unlocked and mounted, and thus accessible to the system and its
78 programs; when "inactive" they are not mounted and thus not accessible.
79 Activation happens automatically at login of the user and usually can
80 only complete after a password (or other authentication token) has been
81 supplied. Deactivation happens after the user fully logged out. A home
82 directory remains active as long as the user is logged in at least
83 once, i.e. has at least one login session. When the user logs in a
84 second time simultaneously the home directory remains active. It is
85 deactivated only after the last of the user's sessions ends.
86
88 The following general options are understood (further options that
89 control the various properties of user records managed by
90 systemd-homed.service are documented further down):
91 --identity=FILE
93 Read the user's JSON record from the specified file. If passed as
94 "-" read the user record from standard input. The supplied JSON
95 object must follow the structure documented in JSON User
96 Records[1]. This option may be used in conjunction with the create
97 and update commands (see below), where it allows configuring the
98 user record in JSON as-is, instead of setting the individual user
99 record properties (see below).
100 --json=FORMAT, -j
102 Controls whether to output the user record in JSON format, if the
103 inspect command (see below) is used. Takes one of "pretty", "short"
104 or "off". If "pretty" human-friendly whitespace and newlines are
105 inserted in the output to make the JSON data more readable. If
106 "short" all superfluous whitespace is suppressed. If "off" (the
107 default) the user information is not shown in JSON format but in a
108 friendly human readable formatting instead. The -j option picks
109 "pretty" when run interactively and "short" otherwise.
110 --export-format=FORMAT, -E, -EE
112 When used with the inspect verb in JSON mode (see above) may be
113 used to suppress certain aspects of the JSON user record on output.
114 Specifically, if "stripped" format is used the binding and runtime
115 fields of the record are removed. If "minimal" format is used the
116 cryptographic signature is removed too. If "full" format is used
117 the full JSON record is shown (this is the default). This option is
118 useful for copying an existing user record to a different system in
119 order to create a similar user there with the same settings.
120 Specifically: homectl inspect -EE | ssh root@othersystem homectl
121 create -i- may be used as simple command line for replicating a
122 user on another host. -E is equivalent to -j
123 --export-format=stripped, -EE to -j --export-format=minimal. Note
124 that when replicating user accounts user records acquired in
125 "stripped" mode will retain the original cryptographic signatures
126 and thus may only be modified when the private key to update them
127 is available on the destination machine. When replicating users in
128 "minimal" mode, the signature is removed during the replication and
129 thus the record will be implicitly signed with the key of the
130 destination machine and may be updated there without any private
131 key replication.
132 -H, --host=
134 Execute the operation remotely. Specify a hostname, or a username
135 and hostname separated by "@", to connect to. The hostname may
136 optionally be suffixed by a port ssh is listening on, separated by
137 ":", and then a container name, separated by "/", which connects
138 directly to a specific container on the specified host. This will
139 use SSH to talk to the remote machine manager instance. Container
140 names may be enumerated with machinectl -H HOST. Put IPv6 addresses
141 in brackets.
142 -M, --machine=
144 Execute operation on a local container. Specify a container name to
145 connect to, optionally prefixed by a user name to connect as and a
146 separating "@" character. If the special string ".host" is used in
147 place of the container name, a connection to the local system is
148 made (which is useful to connect to a specific user's user bus:
149 "--user --machine=lennart@.host"). If the "@" syntax is not used,
150 the connection is made as root user. If the "@" syntax is used
151 either the left hand side or the right hand side may be omitted
152 (but not both) in which case the local user name and ".host" are
153 implied.
154 --no-pager
156 Do not pipe output into a pager.
157 --no-legend
159 Do not print the legend, i.e. column headers and the footer with
160 hints.
161 --no-ask-password
163 Do not query the user for authentication for privileged operations.
164 -h, --help
166 Print a short help text and exit.
167 --version
169 Print a short version string and exit.
170
172 The following options control various properties of the user
173 records/home directories that systemd-homed.service manages. These
174 switches may be used in conjunction with the create and update commands
175 for configuring various aspects of the home directory and the user
176 account:
177 --real-name=NAME, -c NAME
179 The real name for the user. This corresponds with the GECOS field
180 on classic UNIX NSS records.
181 --realm=REALM
183 The realm for the user. The realm associates a user with a specific
184 organization or installation, and allows distinguishing users of
185 the same name defined in different contexts. The realm can be any
186 string that also qualifies as valid DNS domain name, and it is
187 recommended to use the organization's or installation's domain name
188 for this purpose, but this is not enforced nor required. On each
189 system only a single user of the same name may exist, and if a user
190 with the same name and realm is seen it is assumed to refer to the
191 same user while a user with the same name but different realm is
192 considered a different user. Note that this means that two users
193 sharing the same name but with distinct realms are not allowed on
194 the same system. Assigning a realm to a user is optional.
195 --email-address=EMAIL
197 Takes an electronic mail address to associate with the user. On
198 log-in the $EMAIL environment variable is initialized from this
199 value.
200 --location=TEXT
202 Takes location specification for this user. This is free-form text,
203 which might or might not be usable by geo-location applications.
204 Example: --location="Berlin, Germany" or --location="Basement, Room
205 3a"
206 --icon-name=ICON
208 Takes an icon name to associate with the user, following the scheme
209 defined by the Icon Naming Specification[2].
210 --home-dir=PATH, -dPATH
212 Takes a path to use as home directory for the user. Note that this
213 is the directory the user's home directory is mounted to while the
214 user is logged in. This is not where the user's data is actually
215 stored, see --image-path= for that. If not specified defaults to
216 /home/$USER.
217 --uid=UID
219 Takes a preferred numeric UNIX UID to assign this user. If a user
220 is to be created with the specified UID and it is already taken by
221 a different user on the local system then creation of the home
222 directory is refused. Note though, if after creating the home
223 directory it is used on a different system and the configured UID
224 is taken by another user there, then systemd-homed may assign the
225 user a different UID on that system. The specified UID must be
226 outside of the system user range. It is recommended to use the
227 60001...60513 UID range for this purpose. If not specified, the UID
228 is automatically picked. If the home directory is found to be owned
229 by a different UID when logging in, the home directory and
230 everything underneath it will have its ownership changed
231 automatically before login completes.
232 Note that users managed by systemd-homed always have a matching
234 group associated with the same name as well as a GID matching the
235 UID of the user. Thus, configuring the GID separately is not
236 permitted.
237 --member-of=GROUP, -G GROUP
239 Takes a comma-separated list of auxiliary UNIX groups this user
240 shall belong to. Example: --member-of=wheel to provide the user
241 with administrator privileges. Note that systemd-homed does not
242 manage any groups besides a group matching the user in name and
243 numeric UID/GID. Thus any groups listed here must be registered
244 independently, for example with groupadd(8). Any non-existent
245 groups are ignored. This option may be used more than once, in
246 which case all specified group lists are combined. If the user is
247 currently a member of a group which is not listed, the user will be
248 removed from the group.
249 --skel=PATH
251 Takes a file system path to a directory. Specifies the skeleton
252 directory to initialize the home directory with. All files and
253 directories in the specified path are copied into any newly create
254 home directory. If not specified defaults to /etc/skel/.
255 --shell=SHELL
257 Takes a file system path. Specifies the shell binary to execute on
258 terminal logins. If not specified defaults to /bin/bash.
259 --setenv=VARIABLE[=VALUE]
261 Takes an environment variable assignment to set for all user
262 processes. May be used multiple times to set multiple environment
263 variables. When "=" and VALUE are omitted, the value of the
264 variable with the same name in the program environment will be
265 used.
266 Note that a number of other settings also result in environment
268 variables to be set for the user, including --email=, --timezone=
269 and --language=.
270 --timezone=TIMEZONE
272 Takes a time zone location name that sets the timezone for the
273 specified user. When the user logs in the $TZ environment variable
274 is initialized from this setting. Example:
275 --timezone=Europe/Amsterdam will result in the environment variable
276 "TZ=:Europe/Amsterdam". (":" is used intentionally as part of the
277 timezone specification, see tzset(3).)
278 --language=LANG
280 Takes a specifier indicating the preferred language of the user.
281 The $LANG environment variable is initialized from this value on
282 login, and thus a value suitable for this environment variable is
283 accepted here, for example --language=de_DE.UTF8.
284 --ssh-authorized-keys=KEYS
286 Either takes a SSH authorized key line to associate with the user
287 record or a "@" character followed by a path to a file to read one
288 or more such lines from. SSH keys configured this way are made
289 available to SSH to permit access to this home directory and user
290 record. This option may be used more than once to configure
291 multiple SSH keys.
292 --pkcs11-token-uri=URI
294 Takes an RFC 7512 PKCS#11 URI referencing a security token (e.g.
295 YubiKey or PIV smartcard) that shall be able to unlock the user
296 account. The security token URI should reference a security token
297 with exactly one pair of X.509 certificate and private key. A
298 random secret key is then generated, encrypted with the public key
299 of the X.509 certificate, and stored as part of the user record. At
300 login time it is decrypted with the PKCS#11 module and then used to
301 unlock the account and associated resources. See below for an
302 example how to set up authentication with a security token.
303 Instead of a valid PKCS#11 URI, the special strings "list" and
305 "auto" may be specified. If "list" is passed, a brief table of
306 suitable, currently plugged in PKCS#11 hardware tokens is shown,
307 along with their URIs. If "auto" is passed, a suitable PKCS#11
308 hardware token is automatically selected (this operation will fail
309 if there isn't exactly one suitable token discovered). The latter
310 is a useful shortcut for the most common case where a single
311 PKCS#11 hardware token is plugged in.
312 Note that many hardware security tokens implement both PKCS#11/PIV
314 and FIDO2 with the "hmac-secret" extension (for example: the
315 YubiKey 5 series), as supported with the --fido2-device= option
316 below. Both mechanisms are similarly powerful, though FIDO2 is the
317 more modern technology. PKCS#11/PIV tokens have the benefit of
318 being recognizable before authentication and hence can be used for
319 implying the user identity to use for logging in, which FIDO2 does
320 not allow. PKCS#11/PIV devices generally require initialization
321 (i.e. storing a private/public key pair on them, see example below)
322 before they can be used; FIDO2 security tokens generally do not
323 required that, and work out of the box.
324 --fido2-device=PATH
326 Takes a path to a Linux "hidraw" device (e.g. /dev/hidraw1),
327 referring to a FIDO2 security token implementing the "hmac-secret"
328 extension that shall be able to unlock the user account. A random
329 salt value is generated on the host and passed to the FIDO2 device,
330 which calculates a HMAC hash of the salt using an internal secret
331 key. The result is then used as the key to unlock the user account.
332 The random salt is included in the user record, so that whenever
333 authentication is needed it can be passed to the FIDO2 token again.
334 Instead of a valid path to a FIDO2 "hidraw" device the special
336 strings "list" and "auto" may be specified. If "list" is passed, a
337 brief table of suitable discovered FIDO2 devices is shown. If
338 "auto" is passed, a suitable FIDO2 token is automatically selected,
339 if exactly one is discovered. The latter is a useful shortcut for
340 the most common case where a single FIDO2 hardware token is plugged
341 in.
342 Note that FIDO2 devices suitable for this option must implement the
344 "hmac-secret" extension. Most current devices (such as the YubiKey
345 5 series) do. If the extension is not implemented the device cannot
346 be used for unlocking home directories.
347 The FIDO2 device may be subsequently removed by setting the device
349 path to an empty string (e.g. homectl update $USER
350 --fido2-device="").
351 Note that many hardware security tokens implement both FIDO2 and
353 PKCS#11/PIV (and thus may be used with either --fido2-device= or
354 --pkcs11-token-uri=), for a discussion see above.
355 --fido2-with-client-pin=BOOL
357 When enrolling a FIDO2 security token, controls whether to require
358 the user to enter a PIN when unlocking the account (the FIDO2
359 "clientPin" feature). Defaults to "yes". (Note: this setting is
360 without effect if the security token does not support the
361 "clientPin" feature at all, or does not allow enabling or disabling
362 it.)
363 --fido2-with-user-presence=BOOL
365 When enrolling a FIDO2 security token, controls whether to require
366 the user to verify presence (tap the token, the FIDO2 "up" feature)
367 when unlocking the account. Defaults to "yes". (Note: this setting
368 is without effect if the security token does not support the "up"
369 feature at all, or does not allow enabling or disabling it.)
370 --fido2-with-user-verification=BOOL
372 When enrolling a FIDO2 security token, controls whether to require
373 user verification when unlocking the account (the FIDO2 "uv"
374 feature). Defaults to "no". (Note: this setting is without effect
375 if the security token does not support the "uv" feature at all, or
376 does not allow enabling or disabling it.)
377 --recovery-key=BOOL
379 Accepts a boolean argument. If enabled a recovery key is configured
380 for the account. A recovery key is a computer generated access key
381 that may be used to regain access to an account if the password has
382 been forgotten or the authentication token lost. The key is
383 generated and shown on screen, and should be printed or otherwise
384 transferred to a secure location. A recovery key may be entered
385 instead of a regular password to unlock the account.
386 --locked=BOOLEAN
388 Takes a boolean argument. Specifies whether this user account shall
389 be locked. If true logins into this account are prohibited, if
390 false (the default) they are permitted (of course, only if
391 authorization otherwise succeeds).
392 --not-before=TIMESTAMP, --not-after=TIMESTAMP
394 These options take a timestamp string, in the format documented in
395 systemd.time(7) and configures points in time before and after
396 logins into this account are not permitted.
397 --rate-limit-interval=SECS, --rate-limit-burst=NUMBER
399 Configures a rate limit on authentication attempts for this user.
400 If the user attempts to authenticate more often than the specified
401 number, on a specific system, within the specified time interval
402 authentication is refused until the time interval passes. Defaults
403 to 10 times per 1min.
404 --password-hint=TEXT
406 Takes a password hint to store alongside the user record. This
407 string is stored accessible only to privileged users and the user
408 itself and may not be queried by other users. Example:
409 --password-hint="My first pet's name".
410 --enforce-password-policy=BOOL, -P
412 Takes a boolean argument. Configures whether to enforce the
413 system's password policy for this user, regarding quality and
414 strength of selected passwords. Defaults to on. -P is short for
415 ---enforce-password-policy=no.
416 --password-change-now=BOOL
418 Takes a boolean argument. If true the user is asked to change their
419 password on next login.
420 --password-change-min=TIME, --password-change-max=TIME,
422 --password-change-warn=TIME, --password-change-inactive=TIME
423 Each of these options takes a time span specification as argument
424 (in the syntax documented in systemd.time(7)) and configures
425 various aspects of the user's password expiration policy.
426 Specifically, --password-change-min= configures how much time has
427 to pass after changing the password of the user until the password
428 may be changed again. If the user tries to change their password
429 before this time passes the attempt is refused.
430 --password-change-max= configures how soon after it has been
431 changed the password expires and needs to be changed again. After
432 this time passes logging in may only proceed after the password is
433 changed. --password-change-warn= specifies how much earlier than
434 then the time configured with --password-change-max= the user is
435 warned at login to change their password as it will expire soon.
436 Finally --password-change-inactive= configures the time which has
437 to pass after the password as expired until the user is not
438 permitted to log in or change the password anymore. Note that these
439 options only apply to password authentication, and do not apply to
440 other forms of authentication, for example PKCS#11-based security
441 token authentication.
442 --disk-size=BYTES
444 Either takes a size in bytes as argument (possibly using the usual
445 K, M, G, ... suffixes for 1024 base values), a percentage value, or
446 the special strings "min" or "max", and configures the disk space
447 to assign to the user. If a percentage value is specified (i.e. the
448 argument suffixed with "%") it is taken relative to the available
449 disk space of the backing file system. If specified as "min"
450 assigns the minimal disk space permitted by the constraints of the
451 backing file system and other limits, when specified as "max"
452 assigns the maximum disk space available. If the LUKS2 backend is
453 used this configures the size of the loopback file and file system
454 contained therein. For the other storage backends configures disk
455 quota using the filesystem's native quota logic, if available. If
456 not specified, defaults to 85% of the available disk space for the
457 LUKS2 backend and to no quota for the others.
458 --access-mode=MODE
460 Takes a UNIX file access mode written in octal. Configures the
461 access mode of the home directory itself. Note that this is only
462 used when the directory is first created, and the user may change
463 this any time afterwards. Example: --access-mode=0700
464 --umask=MASK
466 Takes the access mode mask (in octal syntax) to apply to newly
467 created files and directories of the user ("umask"). If set this
468 controls the initial umask set for all login sessions of the user,
469 possibly overriding the system's defaults.
470 --nice=NICE
472 Takes the numeric scheduling priority ("nice level") to apply to
473 the processes of the user at login time. Takes a numeric value in
474 the range -20 (highest priority) to 19 (lowest priority).
475 --rlimit=LIMIT=VALUE[:VALUE]
477 Allows configuration of resource limits for processes of this user,
478 see getrlimit(2) for details. Takes a resource limit name (e.g.
479 "LIMIT_NOFILE") followed by an equal sign, followed by a numeric
480 limit. Optionally, separated by colon a second numeric limit may be
481 specified. If two are specified this refers to the soft and hard
482 limits, respectively. If only one limit is specified the setting
483 sets both limits in one.
484 --tasks-max=TASKS
486 Takes a non-zero unsigned integer as argument. Configures the
487 maximum number of tasks (i.e. threads, where each process is at
488 least one thread) the user may have at any given time. This limit
489 applies to all tasks forked off the user's sessions, even if they
490 change user identity via su(1) or a similar tool. Use
491 --rlimit=LIMIT_NPROC= to place a limit on the tasks actually
492 running under the UID of the user, thus excluding any child
493 processes that might have changed user identity. This controls the
494 TasksMax= setting of the per-user systemd slice unit
495 user-$UID.slice. See systemd.resource-control(5) for further
496 details.
497 --memory-high=BYTES, --memory-max=BYTES
499 Set a limit on the memory a user may take up on a system at any
500 given time in bytes (the usual K, M, G, ... suffixes are supported,
501 to the base of 1024). This includes all memory used by the user
502 itself and all processes they forked off that changed user
503 credentials. This controls the MemoryHigh= and MemoryMax= settings
504 of the per-user systemd slice unit user-$UID.slice. See
505 systemd.resource-control(5) for further details.
506 --cpu-weight=WEIGHT, --io-weight=WEIGHT
508 Set CPU and IO scheduling weights of the processes of the user,
509 including those of processes forked off by the user that changed
510 user credentials. Takes a numeric value in the range 1...10000.
511 This controls the CPUWeight= and IOWeight= settings of the per-user
512 systemd slice unit user-$UID.slice. See systemd.resource-control(5)
513 for further details.
514 --storage=STORAGE
516 Selects the storage mechanism to use for this home directory. Takes
517 one of "luks", "fscrypt", "directory", "subvolume", "cifs". For
518 details about these mechanisms, see above. If a new home directory
519 is created and the storage type is not specifically specified,
520 homed.conf(5) defines which default storage to use.
521 --image-path=PATH
523 Takes a file system path. Configures where to place the user's home
524 directory. When LUKS2 storage is used refers to the path to the
525 loopback file, otherwise to the path to the home directory (which
526 may be in /home/ or any other accessible filesystem). When
527 unspecified defaults to /home/$USER.home when LUKS storage is used
528 and /home/$USER.homedir for the other storage mechanisms. Not
529 defined for the "cifs" storage mechanism. To use LUKS2 storage on a
530 regular block device (for example a USB stick) pass the path to the
531 block device here. Specifying the path to a directory here when
532 using LUKS2 storage is not allowed. Similar, specifying the path to
533 a regular file or device node is not allowed if any of the other
534 storage backends are used.
535 --drop-caches=BOOL
537 Automatically flush OS file system caches on logout. This is useful
538 in combination with the fscrypt storage backend to ensure the OS
539 does not keep decrypted versions of the files and directories in
540 memory (and accessible) after logout. This option is also supported
541 on other backends, but should not bring any benefit there. Defaults
542 to off, except if the selected storage backend is fscrypt, where it
543 defaults to on. Note that flushing OS caches will negatively
544 influence performance of the OS shortly after logout.
545 --fs-type=TYPE
547 When LUKS2 storage is used configures the file system type to use
548 inside the home directory LUKS2 container. One of "btrfs", "ext4",
549 "xfs". If not specified homed.conf(5) defines which default file
550 system type to use. Note that "xfs" is not recommended as its
551 support for file system resizing is too limited.
552 --luks-discard=BOOL
554 When LUKS2 storage is used configures whether to enable the
555 "discard" feature of the file system. If enabled the file system on
556 top of the LUKS2 volume will report empty block information to
557 LUKS2 and the loopback file below, ensuring that empty space in the
558 home directory is returned to the backing file system below the
559 LUKS2 volume, resulting in a "sparse" loopback file. This option
560 mostly defaults to off, since this permits over-committing home
561 directories which results in I/O errors if the underlying file
562 system runs full while the upper file system wants to allocate a
563 block. Such I/O errors are generally not handled well by file
564 systems nor applications. When LUKS2 storage is used on top of
565 regular block devices (instead of on top a loopback file) the
566 discard logic defaults to on.
567 --luks-offline-discard=BOOL
569 Similar to --luks-discard=, controls the trimming of the file
570 system. However, while --luks-discard= controls what happens when
571 the home directory is active, --luks-offline-discard= controls what
572 happens when it becomes inactive, i.e. whether to trim/allocate the
573 storage when deactivating the home directory. This option defaults
574 to on, to ensure disk space is minimized while a user is not logged
575 in.
576 --luks-extra-mount-options=OPTIONS
578 Takes a string containing additional mount options to use when
579 mounting the LUKS volume. If specified, this string will be
580 appended to the default, built-in mount options.
581 --luks-cipher=CIPHER, --luks-cipher-mode=MODE,
583 --luks-volume-key-size=BYTES, --luks-pbkdf-type=TYPE,
584 --luks-pbkdf-hash-algorithm=ALGORITHM, --luks-pbkdf-time-cost=SECONDS,
585 --luks-pbkdf-memory-cost=BYTES, --luks-pbkdf-parallel-threads=THREADS
586 Configures various cryptographic parameters for the LUKS2 storage
587 mechanism. See cryptsetup(8) for details on the specific
588 attributes.
589 Note that homectl uses bytes for key size, like /proc/crypto, but
591 cryptsetup(8) uses bits.
592 --auto-resize-mode=
594 Configures whether to automatically grow and/or shrink the backing
595 file system on login and logout. Takes one of the strings "off",
596 "grow", "shrink-and-grow". Only applies to the LUKS2 backend
597 currently, and if the btrfs file system is used inside it (since
598 only then online growing/shrinking of the file system is
599 supported). Defaults to "shrink-and-grow", if LUKS2/btrfs is used,
600 otherwise is off. If set to "off" no automatic shrinking/growing
601 during login or logout is done. If set to "grow" the home area is
602 grown to the size configured via --disk-size= should it currently
603 be smaller. If it already matches the configured size or is larger
604 no operation is executed. If set to "shrink-and-grow" the home area
605 is also resized during logout to the minimal size the used disk
606 space and file system constraints permit. This mode thus ensures
607 that while a home area is activated it is sized to the configured
608 size, but while deactivated it is compacted taking up only the
609 minimal space possible. Note that if the system is powered off
610 abnormally or if the user otherwise not logged out cleanly the
611 shrinking operation will not take place, and the user has to
612 re-login/logout again before it is executed again.
613 --rebalance-weight=
615 Configures the weight parameter for the free disk space rebalancing
616 logic. Only applies to the LUKS2 backend (since for the LUKS2
617 backend disk space is allocated from a per-user loopback file
618 system instead of immediately from a common pool like the other
619 backends do it). In regular intervals free disk space in the active
620 home areas and their backing storage is redistributed among them,
621 taking the weight value configured here into account. Expects an
622 integer in the range 1...10000, or the special string "off". If not
623 specified defaults to 100. The weight is used to scale free space
624 made available to the home areas: a home area with a weight of 200
625 will get twice the free space as one with a weight of 100; a home
626 area with a weight of 50 will get half of that. The backing file
627 system will be assigned space for a weight of 20. If set to "off"
628 no automatic free space distribution is done for this home area.
629 Note that resizing the home area explicitly (with homectl resize
630 see below) will implicitly turn off the automatic rebalancing. To
631 reenable the automatic rebalancing use --rebalance-weight= with an
632 empty parameter.
633 --nosuid=BOOL, --nodev=BOOL, --noexec=BOOL
635 Configures the "nosuid", "nodev" and "noexec" mount options for the
636 home directories. By default "nodev" and "nosuid" are on, while
637 "noexec" is off. For details about these mount options see
638 mount(8).
639 --cifs-domain=DOMAIN, --cifs-user-name=USER, --cifs-service=SERVICE,
641 --cifs-extra-mount-options=OPTIONS
642 Configures the Windows File Sharing (CIFS) domain and user to
643 associate with the home directory/user account, as well as the file
644 share ("service") to mount as directory. The latter is used when
645 "cifs" storage is selected. The file share should be specified in
646 format "//host/share/directory/...". The directory part is optional
647 — if not specified the home directory will be placed in the
648 top-level directory of the share. The --cifs-extra-mount-options=
649 setting allows specifying additional mount options when mounting
650 the share, see mount.cifs(8) for details.
651 --stop-delay=SECS
653 Configures the time the per-user service manager shall continue to
654 run after the all sessions of the user ended. The default is
655 configured in logind.conf(5) (for home directories of LUKS2 storage
656 located on removable media this defaults to 0 though). A longer
657 time makes sure quick, repetitive logins are more efficient as the
658 user's service manager doesn't have to be started every time.
659 --kill-processes=BOOL
661 Configures whether to kill all processes of the user on logout. The
662 default is configured in logind.conf(5).
663 --auto-login=BOOL
665 Takes a boolean argument. Configures whether the graphical UI of
666 the system should automatically log this user in if possible.
667 Defaults to off. If less or more than one user is marked this way
668 automatic login is disabled.
669
671 The following commands are understood:
672 list
674 List all home directories (along with brief details) currently
675 managed by systemd-homed.service. This command is also executed if
676 none is specified on the command line. (Note that the list of users
677 shown by this command does not include users managed by other
678 subsystems, such as system users or any traditional users listed in
679 /etc/passwd.)
680 activate USER [USER...]
682 Activate one or more home directories. The home directories of each
683 listed user will be activated and made available under their mount
684 points (typically in /home/$USER). Note that any home activated
685 this way stays active indefinitely, until it is explicitly
686 deactivated again (with deactivate, see below), or the user logs in
687 and out again and it thus is deactivated due to the automatic
688 deactivation-on-logout logic.
689 Activation of a home directory involves various operations that
691 depend on the selected storage mechanism. If the LUKS2 mechanism is
692 used, this generally involves: inquiring the user for a password,
693 setting up a loopback device, validating and activating the LUKS2
694 volume, checking the file system, mounting the file system, and
695 potentially changing the ownership of all included files to the
696 correct UID/GID.
697 deactivate USER [USER...]
699 Deactivate one or more home directories. This undoes the effect of
700 activate.
701 inspect USER [USER...]
703 Show various details about the specified home directories. This
704 shows various information about the home directory and its user
705 account, including runtime data such as current state, disk use and
706 similar. Combine with --json= to show the detailed JSON user record
707 instead, possibly combined with --export-format= to suppress
708 certain aspects of the output.
709 authenticate USER [USER...]
711 Validate authentication credentials of a home directory. This
712 queries the caller for a password (or similar) and checks that it
713 correctly unlocks the home directory. This leaves the home
714 directory in the state it is in, i.e. it leaves the home directory
715 in inactive state if it was inactive before, and in active state if
716 it was active before.
717 create USER, create --identity=PATH [USER]
719 Create a new home directory/user account of the specified name. Use
720 the various user record property options (as documented above) to
721 control various aspects of the home directory and its user
722 accounts.
723 The specified user name should follow the strict syntax described
725 on User/Group Name Syntax[3].
726 remove USER
728 Remove a home directory/user account. This will remove both the
729 home directory's user record and the home directory itself, and
730 thus delete all files and directories owned by the user.
731 update USER, update --identity=PATH [USER]
733 Update a home directory/user account. Use the various user record
734 property options (as documented above) to make changes to the
735 account, or alternatively provide a full, updated JSON user record
736 via the --identity= option.
737 Note that changes to user records not signed by a cryptographic
739 private key available locally are not permitted, unless --identity=
740 is used with a user record that is already correctly signed by a
741 recognized private key.
742 passwd USER
744 Change the password of the specified home directory/user account.
745 resize USER BYTES
747 Change the disk space assigned to the specified home directory. If
748 the LUKS2 storage mechanism is used this will automatically resize
749 the loopback file and the file system contained within. Note that
750 if "ext4" is used inside of the LUKS2 volume, it is necessary to
751 deactivate the home directory before shrinking it (i.e the user has
752 to log out). Growing can be done while the home directory is
753 active. If "xfs" is used inside of the LUKS2 volume the home
754 directory may not be shrunk whatsoever. On all three of "ext4",
755 "xfs" and "btrfs" the home directory may be grown while the user is
756 logged in, and on the latter also shrunk while the user is logged
757 in. If the "subvolume", "directory", "fscrypt" storage mechanisms
758 are used, resizing will change file system quota. The size
759 parameter may make use of the usual suffixes B, K, M, G, T (to the
760 base of 1024). The special strings "min" and "max" may be specified
761 in place of a numeric size value, for minimizing or maximizing disk
762 space assigned to the home area, taking constraints of the file
763 system, disk usage inside the home area and on the backing storage
764 into account.
765 lock USER
767 Temporarily suspend access to the user's home directory and remove
768 any associated cryptographic keys from memory. Any attempts to
769 access the user's home directory will stall until the home
770 directory is unlocked again (i.e. re-authenticated). This
771 functionality is primarily intended to be used during system
772 suspend to make sure the user's data cannot be accessed until the
773 user re-authenticates on resume. This operation is only defined for
774 home directories that use the LUKS2 storage mechanism.
775 unlock USER
777 Resume access to the user's home directory again, undoing the
778 effect of lock above. This requires authentication of the user, as
779 the cryptographic keys required for access to the home directory
780 need to be reacquired.
781 lock-all
783 Execute the lock command on all suitable home directories at once.
784 This operation is generally executed on system suspend (i.e. by
785 systemctl suspend and related commands), to ensure all active
786 user's cryptographic keys for accessing their home directories are
787 removed from memory.
788 deactivate-all
790 Execute the deactivate command on all active home directories at
791 once. This operation is generally executed on system shut down
792 (i.e. by systemctl poweroff and related commands), to ensure all
793 active user's home directories are fully deactivated before /home/
794 and related file systems are unmounted.
795 with USER COMMAND...
797 Activate the specified user's home directory, run the specified
798 command (under the caller's identity, not the specified user's) and
799 deactivate the home directory afterwards again (unless the user is
800 logged in otherwise). This command is useful for running privileged
801 backup scripts and such, but requires authentication with the
802 user's credentials in order to be able to unlock the user's home
803 directory.
804 rebalance
806 Rebalance free disk space between active home areas and the backing
807 storage. See --rebalance-weight= above. This executes no operation
808 unless there's at least one active LUKS2 home area that has disk
809 space rebalancing enabled. This operation is synchronous: it will
810 only complete once disk space is rebalanced according to the
811 rebalancing weights. Note that rebalancing also takes place
812 automatically in the background in regular intervals. Use this
813 command to synchronously ensure disk space is properly
814 redistributed before initiating an operation requiring large
815 amounts of disk space.
816
818 On success, 0 is returned, a non-zero failure code otherwise.
819 When a command is invoked with with, the exit status of the child is
821 propagated. Effectively, homectl will exit without error if the command
822 is successfully invoked and finishes successfully.
823
825 $SYSTEMD_LOG_LEVEL
826 The maximum log level of emitted messages (messages with a higher
827 log level, i.e. less important ones, will be suppressed). Either
828 one of (in order of decreasing importance) emerg, alert, crit, err,
829 warning, notice, info, debug, or an integer in the range 0...7. See
830 syslog(3) for more information.
831 $SYSTEMD_LOG_COLOR
833 A boolean. If true, messages written to the tty will be colored
834 according to priority.
835 This setting is only useful when messages are written directly to
837 the terminal, because journalctl(1) and other tools that display
838 logs will color messages based on the log level on their own.
839 $SYSTEMD_LOG_TIME
841 A boolean. If true, console log messages will be prefixed with a
842 timestamp.
843 This setting is only useful when messages are written directly to
845 the terminal or a file, because journalctl(1) and other tools that
846 display logs will attach timestamps based on the entry metadata on
847 their own.
848 $SYSTEMD_LOG_LOCATION
850 A boolean. If true, messages will be prefixed with a filename and
851 line number in the source code where the message originates.
852 Note that the log location is often attached as metadata to journal
854 entries anyway. Including it directly in the message text can
855 nevertheless be convenient when debugging programs.
856 $SYSTEMD_LOG_TID
858 A boolean. If true, messages will be prefixed with the current
859 numerical thread ID (TID).
860 Note that the this information is attached as metadata to journal
862 entries anyway. Including it directly in the message text can
863 nevertheless be convenient when debugging programs.
864 $SYSTEMD_LOG_TARGET
866 The destination for log messages. One of console (log to the
867 attached tty), console-prefixed (log to the attached tty but with
868 prefixes encoding the log level and "facility", see syslog(3), kmsg
869 (log to the kernel circular log buffer), journal (log to the
870 journal), journal-or-kmsg (log to the journal if available, and to
871 kmsg otherwise), auto (determine the appropriate log target
872 automatically, the default), null (disable log output).
873 $SYSTEMD_PAGER
875 Pager to use when --no-pager is not given; overrides $PAGER. If
876 neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
877 pager implementations are tried in turn, including less(1) and
878 more(1), until one is found. If no pager implementation is
879 discovered no pager is invoked. Setting this environment variable
880 to an empty string or the value "cat" is equivalent to passing
881 --no-pager.
882 $SYSTEMD_LESS
884 Override the options passed to less (by default "FRSXMK").
885 Users might want to change two options in particular:
887 K
889 This option instructs the pager to exit immediately when Ctrl+C
890 is pressed. To allow less to handle Ctrl+C itself to switch
891 back to the pager command prompt, unset this option.
892 If the value of $SYSTEMD_LESS does not include "K", and the
894 pager that is invoked is less, Ctrl+C will be ignored by the
895 executable, and needs to be handled by the pager.
896 X
898 This option instructs the pager to not send termcap
899 initialization and deinitialization strings to the terminal. It
900 is set by default to allow command output to remain visible in
901 the terminal even after the pager exits. Nevertheless, this
902 prevents some pager functionality from working, in particular
903 paged output cannot be scrolled with the mouse.
904 See less(1) for more discussion.
906 $SYSTEMD_LESSCHARSET
908 Override the charset passed to less (by default "utf-8", if the
909 invoking terminal is determined to be UTF-8 compatible).
910 $SYSTEMD_PAGERSECURE
912 Takes a boolean argument. When true, the "secure" mode of the pager
913 is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
914 at all, secure mode is enabled if the effective UID is not the same
915 as the owner of the login session, see geteuid(2) and
916 sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
917 when invoking the pager, and the pager shall disable commands that
918 open or create new files or start new subprocesses. When
919 $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
920 to implement secure mode will not be used. (Currently only less(1)
921 implements secure mode.)
922 Note: when commands are invoked with elevated privileges, for
924 example under sudo(8) or pkexec(1), care must be taken to ensure
925 that unintended interactive features are not enabled. "Secure" mode
926 for the pager may be enabled automatically as describe above.
927 Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
928 environment allows the user to invoke arbitrary commands. Note that
929 if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
930 $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
931 completely disable the pager using --no-pager instead.
932 $SYSTEMD_COLORS
934 Takes a boolean argument. When true, systemd and related utilities
935 will use colors in their output, otherwise the output will be
936 monochrome. Additionally, the variable can take one of the
937 following special values: "16", "256" to restrict the use of colors
938 to the base 16 or 256 ANSI colors, respectively. This can be
939 specified to override the automatic decision based on $TERM and
940 what the console is connected to.
941 $SYSTEMD_URLIFY
943 The value must be a boolean. Controls whether clickable links
944 should be generated in the output for terminal emulators supporting
945 this. This can be specified to override the decision that systemd
946 makes based on $TERM and other conditions.
947
949 Example 1. Create a user "waldo" in the administrator group "wheel",
950 and assign 500 MiB disk space to them.
951 homectl create waldo --real-name="Waldo McWaldo" -G wheel --disk-size=500M
953 Example 2. Create a user "wally" on a USB stick, and assign a maximum
955 of 500 concurrent tasks to them.
956 homectl create wally --real-name="Wally McWally" --image-path=/dev/disk/by-id/usb-SanDisk_Ultra_Fit_476fff954b2b5c44-0:0 --tasks-max=500
958 Example 3. Change nice level of user "odlaw" to +5 and make sure the
960 environment variable $SOME is set to the string "THING" for them on
961 login.
962 homectl update odlaw --nice=5 --setenv=SOME=THING
964 Example 4. Set up authentication with a YubiKey security token using
966 PKCS#11/PIV:
967 # Clear the Yubikey from any old keys (careful!)
969 ykman piv reset
970 # Generate a new private/public key pair on the device, store the public key in 'pubkey.pem'.
972 ykman piv generate-key -a RSA2048 9d pubkey.pem
973 # Create a self-signed certificate from this public key, and store it on the device.
975 ykman piv generate-certificate --subject "Knobelei" 9d pubkey.pem
976 # We don't need the public key on disk anymore
978 rm pubkey.pem
979 # Allow the security token to unlock the account of user 'lafcadio'.
981 homectl update lafcadio --pkcs11-token-uri=auto
982 Example 5. Set up authentication with a FIDO2 security token:
984 # Allow a FIDO2 security token to unlock the account of user 'nihilbaxter'.
986 homectl update nihilbaxter --fido2-device=auto
987
989 systemd(1), systemd-homed.service(8), homed.conf(5), userdbctl(1),
990 useradd(8), cryptsetup(8)
991
993 1. JSON User Records
994 https://systemd.io/USER_RECORD
995 2. Icon Naming Specification
997 https://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
998 3. User/Group Name Syntax
1000 https://systemd.io/USER_NAMES
1001systemd 250 HOMECTL(1)