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 changing this option for existing home directories
234 generally has no effect on home directories that already have been
235 registered locally (have a local binding), as the UID used for an
236 account on the local system is determined when the home directory
237 is first activated on it, and then remains in effect until the home
238 directory is removed.
239 Note that users managed by systemd-homed always have a matching
241 group associated with the same name as well as a GID matching the
242 UID of the user. Thus, configuring the GID separately is not
243 permitted.
244 --member-of=GROUP, -G GROUP
246 Takes a comma-separated list of auxiliary UNIX groups this user
247 shall belong to. Example: --member-of=wheel to provide the user
248 with administrator privileges. Note that systemd-homed does not
249 manage any groups besides a group matching the user in name and
250 numeric UID/GID. Thus any groups listed here must be registered
251 independently, for example with groupadd(8). Any non-existent
252 groups are ignored. This option may be used more than once, in
253 which case all specified group lists are combined. If the user is
254 currently a member of a group which is not listed, the user will be
255 removed from the group.
256 --skel=PATH
258 Takes a file system path to a directory. Specifies the skeleton
259 directory to initialize the home directory with. All files and
260 directories in the specified path are copied into any newly create
261 home directory. If not specified defaults to /etc/skel/.
262 --shell=SHELL
264 Takes a file system path. Specifies the shell binary to execute on
265 terminal logins. If not specified defaults to /bin/bash.
266 --setenv=VARIABLE[=VALUE]
268 Takes an environment variable assignment to set for all user
269 processes. May be used multiple times to set multiple environment
270 variables. When "=" and VALUE are omitted, the value of the
271 variable with the same name in the program environment will be
272 used.
273 Note that a number of other settings also result in environment
275 variables to be set for the user, including --email=, --timezone=
276 and --language=.
277 --timezone=TIMEZONE
279 Takes a time zone location name that sets the timezone for the
280 specified user. When the user logs in the $TZ environment variable
281 is initialized from this setting. Example:
282 --timezone=Europe/Amsterdam will result in the environment variable
283 "TZ=:Europe/Amsterdam". (":" is used intentionally as part of the
284 timezone specification, see tzset(3).)
285 --language=LANG
287 Takes a specifier indicating the preferred language of the user.
288 The $LANG environment variable is initialized from this value on
289 login, and thus a value suitable for this environment variable is
290 accepted here, for example --language=de_DE.UTF8.
291 --ssh-authorized-keys=KEYS
293 Either takes a SSH authorized key line to associate with the user
294 record or a "@" character followed by a path to a file to read one
295 or more such lines from. SSH keys configured this way are made
296 available to SSH to permit access to this home directory and user
297 record. This option may be used more than once to configure
298 multiple SSH keys.
299 --pkcs11-token-uri=URI
301 Takes an RFC 7512 PKCS#11 URI referencing a security token (e.g.
302 YubiKey or PIV smartcard) that shall be able to unlock the user
303 account. The security token URI should reference a security token
304 with exactly one pair of X.509 certificate and private key. A
305 random secret key is then generated, encrypted with the public key
306 of the X.509 certificate, and stored as part of the user record. At
307 login time it is decrypted with the PKCS#11 module and then used to
308 unlock the account and associated resources. See below for an
309 example how to set up authentication with a security token.
310 Instead of a valid PKCS#11 URI, the special strings "list" and
312 "auto" may be specified. If "list" is passed, a brief table of
313 suitable, currently plugged in PKCS#11 hardware tokens is shown,
314 along with their URIs. If "auto" is passed, a suitable PKCS#11
315 hardware token is automatically selected (this operation will fail
316 if there isn't exactly one suitable token discovered). The latter
317 is a useful shortcut for the most common case where a single
318 PKCS#11 hardware token is plugged in.
319 Note that many hardware security tokens implement both PKCS#11/PIV
321 and FIDO2 with the "hmac-secret" extension (for example: the
322 YubiKey 5 series), as supported with the --fido2-device= option
323 below. Both mechanisms are similarly powerful, though FIDO2 is the
324 more modern technology. PKCS#11/PIV tokens have the benefit of
325 being recognizable before authentication and hence can be used for
326 implying the user identity to use for logging in, which FIDO2 does
327 not allow. PKCS#11/PIV devices generally require initialization
328 (i.e. storing a private/public key pair on them, see example below)
329 before they can be used; FIDO2 security tokens generally do not
330 required that, and work out of the box.
331 --fido2-credential-algorithm=STRING
333 Specify COSE algorithm used in credential generation. The default
334 value is "es256". Supported values are "es256", "rs256" and
335 "eddsa".
336 "es256" denotes ECDSA over NIST P-256 with SHA-256. "rs256"
338 denotes 2048-bit RSA with PKCS#1.5 padding and SHA-256. "eddsa"
339 denotes EDDSA over Curve25519 with SHA-512.
340 Note that your authenticator may not support some algorithms.
342 --fido2-device=PATH
344 Takes a path to a Linux "hidraw" device (e.g. /dev/hidraw1),
345 referring to a FIDO2 security token implementing the "hmac-secret"
346 extension that shall be able to unlock the user account. A random
347 salt value is generated on the host and passed to the FIDO2 device,
348 which calculates a HMAC hash of the salt using an internal secret
349 key. The result is then used as the key to unlock the user account.
350 The random salt is included in the user record, so that whenever
351 authentication is needed it can be passed to the FIDO2 token again.
352 Instead of a valid path to a FIDO2 "hidraw" device the special
354 strings "list" and "auto" may be specified. If "list" is passed, a
355 brief table of suitable discovered FIDO2 devices is shown. If
356 "auto" is passed, a suitable FIDO2 token is automatically selected,
357 if exactly one is discovered. The latter is a useful shortcut for
358 the most common case where a single FIDO2 hardware token is plugged
359 in.
360 Note that FIDO2 devices suitable for this option must implement the
362 "hmac-secret" extension. Most current devices (such as the YubiKey
363 5 series) do. If the extension is not implemented the device cannot
364 be used for unlocking home directories.
365 The FIDO2 device may be subsequently removed by setting the device
367 path to an empty string (e.g. homectl update $USER
368 --fido2-device="").
369 Note that many hardware security tokens implement both FIDO2 and
371 PKCS#11/PIV (and thus may be used with either --fido2-device= or
372 --pkcs11-token-uri=), for a discussion see above.
373 --fido2-with-client-pin=BOOL
375 When enrolling a FIDO2 security token, controls whether to require
376 the user to enter a PIN when unlocking the account (the FIDO2
377 "clientPin" feature). Defaults to "yes". (Note: this setting is
378 without effect if the security token does not support the
379 "clientPin" feature at all, or does not allow enabling or disabling
380 it.)
381 --fido2-with-user-presence=BOOL
383 When enrolling a FIDO2 security token, controls whether to require
384 the user to verify presence (tap the token, the FIDO2 "up" feature)
385 when unlocking the account. Defaults to "yes". (Note: this setting
386 is without effect if the security token does not support the "up"
387 feature at all, or does not allow enabling or disabling it.)
388 --fido2-with-user-verification=BOOL
390 When enrolling a FIDO2 security token, controls whether to require
391 user verification when unlocking the account (the FIDO2 "uv"
392 feature). Defaults to "no". (Note: this setting is without effect
393 if the security token does not support the "uv" feature at all, or
394 does not allow enabling or disabling it.)
395 --recovery-key=BOOL
397 Accepts a boolean argument. If enabled a recovery key is configured
398 for the account. A recovery key is a computer generated access key
399 that may be used to regain access to an account if the password has
400 been forgotten or the authentication token lost. The key is
401 generated and shown on screen, and should be printed or otherwise
402 transferred to a secure location. A recovery key may be entered
403 instead of a regular password to unlock the account.
404 --locked=BOOLEAN
406 Takes a boolean argument. Specifies whether this user account shall
407 be locked. If true logins into this account are prohibited, if
408 false (the default) they are permitted (of course, only if
409 authorization otherwise succeeds).
410 --not-before=TIMESTAMP, --not-after=TIMESTAMP
412 These options take a timestamp string, in the format documented in
413 systemd.time(7) and configures points in time before and after
414 logins into this account are not permitted.
415 --rate-limit-interval=SECS, --rate-limit-burst=NUMBER
417 Configures a rate limit on authentication attempts for this user.
418 If the user attempts to authenticate more often than the specified
419 number, on a specific system, within the specified time interval
420 authentication is refused until the time interval passes. Defaults
421 to 10 times per 1min.
422 --password-hint=TEXT
424 Takes a password hint to store alongside the user record. This
425 string is stored accessible only to privileged users and the user
426 itself and may not be queried by other users. Example:
427 --password-hint="My first pet's name".
428 --enforce-password-policy=BOOL, -P
430 Takes a boolean argument. Configures whether to enforce the
431 system's password policy for this user, regarding quality and
432 strength of selected passwords. Defaults to on. -P is short for
433 ---enforce-password-policy=no.
434 --password-change-now=BOOL
436 Takes a boolean argument. If true the user is asked to change their
437 password on next login.
438 --password-change-min=TIME, --password-change-max=TIME,
440 --password-change-warn=TIME, --password-change-inactive=TIME
441 Each of these options takes a time span specification as argument
442 (in the syntax documented in systemd.time(7)) and configures
443 various aspects of the user's password expiration policy.
444 Specifically, --password-change-min= configures how much time has
445 to pass after changing the password of the user until the password
446 may be changed again. If the user tries to change their password
447 before this time passes the attempt is refused.
448 --password-change-max= configures how soon after it has been
449 changed the password expires and needs to be changed again. After
450 this time passes logging in may only proceed after the password is
451 changed. --password-change-warn= specifies how much earlier than
452 then the time configured with --password-change-max= the user is
453 warned at login to change their password as it will expire soon.
454 Finally --password-change-inactive= configures the time which has
455 to pass after the password as expired until the user is not
456 permitted to log in or change the password anymore. Note that these
457 options only apply to password authentication, and do not apply to
458 other forms of authentication, for example PKCS#11-based security
459 token authentication.
460 --disk-size=BYTES
462 Either takes a size in bytes as argument (possibly using the usual
463 K, M, G, ... suffixes for 1024 base values), a percentage value, or
464 the special strings "min" or "max", and configures the disk space
465 to assign to the user. If a percentage value is specified (i.e. the
466 argument suffixed with "%") it is taken relative to the available
467 disk space of the backing file system. If specified as "min"
468 assigns the minimal disk space permitted by the constraints of the
469 backing file system and other limits, when specified as "max"
470 assigns the maximum disk space available. If the LUKS2 backend is
471 used this configures the size of the loopback file and file system
472 contained therein. For the other storage backends configures disk
473 quota using the filesystem's native quota logic, if available. If
474 not specified, defaults to 85% of the available disk space for the
475 LUKS2 backend and to no quota for the others.
476 --access-mode=MODE
478 Takes a UNIX file access mode written in octal. Configures the
479 access mode of the home directory itself. Note that this is only
480 used when the directory is first created, and the user may change
481 this any time afterwards. Example: --access-mode=0700
482 --umask=MASK
484 Takes the access mode mask (in octal syntax) to apply to newly
485 created files and directories of the user ("umask"). If set this
486 controls the initial umask set for all login sessions of the user,
487 possibly overriding the system's defaults.
488 --nice=NICE
490 Takes the numeric scheduling priority ("nice level") to apply to
491 the processes of the user at login time. Takes a numeric value in
492 the range -20 (highest priority) to 19 (lowest priority).
493 --rlimit=LIMIT=VALUE[:VALUE]
495 Allows configuration of resource limits for processes of this user,
496 see getrlimit(2) for details. Takes a resource limit name (e.g.
497 "LIMIT_NOFILE") followed by an equal sign, followed by a numeric
498 limit. Optionally, separated by colon a second numeric limit may be
499 specified. If two are specified this refers to the soft and hard
500 limits, respectively. If only one limit is specified the setting
501 sets both limits in one.
502 --tasks-max=TASKS
504 Takes a non-zero unsigned integer as argument. Configures the
505 maximum number of tasks (i.e. threads, where each process is at
506 least one thread) the user may have at any given time. This limit
507 applies to all tasks forked off the user's sessions, even if they
508 change user identity via su(1) or a similar tool. Use
509 --rlimit=LIMIT_NPROC= to place a limit on the tasks actually
510 running under the UID of the user, thus excluding any child
511 processes that might have changed user identity. This controls the
512 TasksMax= setting of the per-user systemd slice unit
513 user-$UID.slice. See systemd.resource-control(5) for further
514 details.
515 --memory-high=BYTES, --memory-max=BYTES
517 Set a limit on the memory a user may take up on a system at any
518 given time in bytes (the usual K, M, G, ... suffixes are supported,
519 to the base of 1024). This includes all memory used by the user
520 itself and all processes they forked off that changed user
521 credentials. This controls the MemoryHigh= and MemoryMax= settings
522 of the per-user systemd slice unit user-$UID.slice. See
523 systemd.resource-control(5) for further details.
524 --cpu-weight=WEIGHT, --io-weight=WEIGHT
526 Set CPU and IO scheduling weights of the processes of the user,
527 including those of processes forked off by the user that changed
528 user credentials. Takes a numeric value in the range 1...10000.
529 This controls the CPUWeight= and IOWeight= settings of the per-user
530 systemd slice unit user-$UID.slice. See systemd.resource-control(5)
531 for further details.
532 --storage=STORAGE
534 Selects the storage mechanism to use for this home directory. Takes
535 one of "luks", "fscrypt", "directory", "subvolume", "cifs". For
536 details about these mechanisms, see above. If a new home directory
537 is created and the storage type is not specifically specified,
538 homed.conf(5) defines which default storage to use.
539 --image-path=PATH
541 Takes a file system path. Configures where to place the user's home
542 directory. When LUKS2 storage is used refers to the path to the
543 loopback file, otherwise to the path to the home directory (which
544 may be in /home/ or any other accessible filesystem). When
545 unspecified defaults to /home/$USER.home when LUKS storage is used
546 and /home/$USER.homedir for the other storage mechanisms. Not
547 defined for the "cifs" storage mechanism. To use LUKS2 storage on a
548 regular block device (for example a USB stick) pass the path to the
549 block device here. Specifying the path to a directory here when
550 using LUKS2 storage is not allowed. Similar, specifying the path to
551 a regular file or device node is not allowed if any of the other
552 storage backends are used.
553 --drop-caches=BOOL
555 Automatically flush OS file system caches on logout. This is useful
556 in combination with the fscrypt storage backend to ensure the OS
557 does not keep decrypted versions of the files and directories in
558 memory (and accessible) after logout. This option is also supported
559 on other backends, but should not bring any benefit there. Defaults
560 to off, except if the selected storage backend is fscrypt, where it
561 defaults to on. Note that flushing OS caches will negatively
562 influence performance of the OS shortly after logout.
563 --fs-type=TYPE
565 When LUKS2 storage is used configures the file system type to use
566 inside the home directory LUKS2 container. One of "btrfs", "ext4",
567 "xfs". If not specified homed.conf(5) defines which default file
568 system type to use. Note that "xfs" is not recommended as its
569 support for file system resizing is too limited.
570 --luks-discard=BOOL
572 When LUKS2 storage is used configures whether to enable the
573 "discard" feature of the file system. If enabled the file system on
574 top of the LUKS2 volume will report empty block information to
575 LUKS2 and the loopback file below, ensuring that empty space in the
576 home directory is returned to the backing file system below the
577 LUKS2 volume, resulting in a "sparse" loopback file. This option
578 mostly defaults to off, since this permits over-committing home
579 directories which results in I/O errors if the underlying file
580 system runs full while the upper file system wants to allocate a
581 block. Such I/O errors are generally not handled well by file
582 systems nor applications. When LUKS2 storage is used on top of
583 regular block devices (instead of on top a loopback file) the
584 discard logic defaults to on.
585 --luks-offline-discard=BOOL
587 Similar to --luks-discard=, controls the trimming of the file
588 system. However, while --luks-discard= controls what happens when
589 the home directory is active, --luks-offline-discard= controls what
590 happens when it becomes inactive, i.e. whether to trim/allocate the
591 storage when deactivating the home directory. This option defaults
592 to on, to ensure disk space is minimized while a user is not logged
593 in.
594 --luks-extra-mount-options=OPTIONS
596 Takes a string containing additional mount options to use when
597 mounting the LUKS volume. If specified, this string will be
598 appended to the default, built-in mount options.
599 --luks-cipher=CIPHER, --luks-cipher-mode=MODE,
601 --luks-volume-key-size=BYTES, --luks-pbkdf-type=TYPE,
602 --luks-pbkdf-hash-algorithm=ALGORITHM,
603 --luks-pbkdf-force-iterations=ITERATIONS,
604 --luks-pbkdf-time-cost=SECONDS, --luks-pbkdf-memory-cost=BYTES,
605 --luks-pbkdf-parallel-threads=THREADS, --luks-sector-size=BYTES
606 Configures various cryptographic parameters for the LUKS2 storage
607 mechanism. See cryptsetup(8) for details on the specific
608 attributes.
609 Note that homectl uses bytes for key size, like /proc/crypto, but
611 cryptsetup(8) uses bits.
612 --auto-resize-mode=
614 Configures whether to automatically grow and/or shrink the backing
615 file system on login and logout. Takes one of the strings "off",
616 "grow", "shrink-and-grow". Only applies to the LUKS2 backend
617 currently, and if the btrfs file system is used inside it (since
618 only then online growing/shrinking of the file system is
619 supported). Defaults to "shrink-and-grow", if LUKS2/btrfs is used,
620 otherwise is off. If set to "off" no automatic shrinking/growing
621 during login or logout is done. If set to "grow" the home area is
622 grown to the size configured via --disk-size= should it currently
623 be smaller. If it already matches the configured size or is larger
624 no operation is executed. If set to "shrink-and-grow" the home area
625 is also resized during logout to the minimal size the used disk
626 space and file system constraints permit. This mode thus ensures
627 that while a home area is activated it is sized to the configured
628 size, but while deactivated it is compacted taking up only the
629 minimal space possible. Note that if the system is powered off
630 abnormally or if the user otherwise not logged out cleanly the
631 shrinking operation will not take place, and the user has to
632 re-login/logout again before it is executed again.
633 --rebalance-weight=
635 Configures the weight parameter for the free disk space rebalancing
636 logic. Only applies to the LUKS2 backend (since for the LUKS2
637 backend disk space is allocated from a per-user loopback file
638 system instead of immediately from a common pool like the other
639 backends do it). In regular intervals free disk space in the active
640 home areas and their backing storage is redistributed among them,
641 taking the weight value configured here into account. Expects an
642 integer in the range 1...10000, or the special string "off". If not
643 specified defaults to 100. The weight is used to scale free space
644 made available to the home areas: a home area with a weight of 200
645 will get twice the free space as one with a weight of 100; a home
646 area with a weight of 50 will get half of that. The backing file
647 system will be assigned space for a weight of 20. If set to "off"
648 no automatic free space distribution is done for this home area.
649 Note that resizing the home area explicitly (with homectl resize
650 see below) will implicitly turn off the automatic rebalancing. To
651 reenable the automatic rebalancing use --rebalance-weight= with an
652 empty parameter.
653 --nosuid=BOOL, --nodev=BOOL, --noexec=BOOL
655 Configures the "nosuid", "nodev" and "noexec" mount options for the
656 home directories. By default "nodev" and "nosuid" are on, while
657 "noexec" is off. For details about these mount options see
658 mount(8).
659 --cifs-domain=DOMAIN, --cifs-user-name=USER, --cifs-service=SERVICE,
661 --cifs-extra-mount-options=OPTIONS
662 Configures the Windows File Sharing (CIFS) domain and user to
663 associate with the home directory/user account, as well as the file
664 share ("service") to mount as directory. The latter is used when
665 "cifs" storage is selected. The file share should be specified in
666 format "//host/share/directory/...". The directory part is optional
667 — if not specified the home directory will be placed in the
668 top-level directory of the share. The --cifs-extra-mount-options=
669 setting allows specifying additional mount options when mounting
670 the share, see mount.cifs(8) for details.
671 --stop-delay=SECS
673 Configures the time the per-user service manager shall continue to
674 run after the all sessions of the user ended. The default is
675 configured in logind.conf(5) (for home directories of LUKS2 storage
676 located on removable media this defaults to 0 though). A longer
677 time makes sure quick, repetitive logins are more efficient as the
678 user's service manager doesn't have to be started every time.
679 --kill-processes=BOOL
681 Configures whether to kill all processes of the user on logout. The
682 default is configured in logind.conf(5).
683 --auto-login=BOOL
685 Takes a boolean argument. Configures whether the graphical UI of
686 the system should automatically log this user in if possible.
687 Defaults to off. If less or more than one user is marked this way
688 automatic login is disabled.
689
691 The following commands are understood:
692 list
694 List all home directories (along with brief details) currently
695 managed by systemd-homed.service. This command is also executed if
696 none is specified on the command line. (Note that the list of users
697 shown by this command does not include users managed by other
698 subsystems, such as system users or any traditional users listed in
699 /etc/passwd.)
700 activate USER [USER...]
702 Activate one or more home directories. The home directories of each
703 listed user will be activated and made available under their mount
704 points (typically in /home/$USER). Note that any home activated
705 this way stays active indefinitely, until it is explicitly
706 deactivated again (with deactivate, see below), or the user logs in
707 and out again and it thus is deactivated due to the automatic
708 deactivation-on-logout logic.
709 Activation of a home directory involves various operations that
711 depend on the selected storage mechanism. If the LUKS2 mechanism is
712 used, this generally involves: inquiring the user for a password,
713 setting up a loopback device, validating and activating the LUKS2
714 volume, checking the file system, mounting the file system, and
715 potentially changing the ownership of all included files to the
716 correct UID/GID.
717 deactivate USER [USER...]
719 Deactivate one or more home directories. This undoes the effect of
720 activate.
721 inspect USER [USER...]
723 Show various details about the specified home directories. This
724 shows various information about the home directory and its user
725 account, including runtime data such as current state, disk use and
726 similar. Combine with --json= to show the detailed JSON user record
727 instead, possibly combined with --export-format= to suppress
728 certain aspects of the output.
729 authenticate USER [USER...]
731 Validate authentication credentials of a home directory. This
732 queries the caller for a password (or similar) and checks that it
733 correctly unlocks the home directory. This leaves the home
734 directory in the state it is in, i.e. it leaves the home directory
735 in inactive state if it was inactive before, and in active state if
736 it was active before.
737 create USER, create --identity=PATH [USER]
739 Create a new home directory/user account of the specified name. Use
740 the various user record property options (as documented above) to
741 control various aspects of the home directory and its user
742 accounts.
743 The specified user name should follow the strict syntax described
745 on User/Group Name Syntax[3].
746 remove USER
748 Remove a home directory/user account. This will remove both the
749 home directory's user record and the home directory itself, and
750 thus delete all files and directories owned by the user.
751 update USER, update --identity=PATH [USER]
753 Update a home directory/user account. Use the various user record
754 property options (as documented above) to make changes to the
755 account, or alternatively provide a full, updated JSON user record
756 via the --identity= option.
757 Note that changes to user records not signed by a cryptographic
759 private key available locally are not permitted, unless --identity=
760 is used with a user record that is already correctly signed by a
761 recognized private key.
762 passwd USER
764 Change the password of the specified home directory/user account.
765 resize USER BYTES
767 Change the disk space assigned to the specified home directory. If
768 the LUKS2 storage mechanism is used this will automatically resize
769 the loopback file and the file system contained within. Note that
770 if "ext4" is used inside of the LUKS2 volume, it is necessary to
771 deactivate the home directory before shrinking it (i.e the user has
772 to log out). Growing can be done while the home directory is
773 active. If "xfs" is used inside of the LUKS2 volume the home
774 directory may not be shrunk whatsoever. On all three of "ext4",
775 "xfs" and "btrfs" the home directory may be grown while the user is
776 logged in, and on the latter also shrunk while the user is logged
777 in. If the "subvolume", "directory", "fscrypt" storage mechanisms
778 are used, resizing will change file system quota. The size
779 parameter may make use of the usual suffixes B, K, M, G, T (to the
780 base of 1024). The special strings "min" and "max" may be specified
781 in place of a numeric size value, for minimizing or maximizing disk
782 space assigned to the home area, taking constraints of the file
783 system, disk usage inside the home area and on the backing storage
784 into account.
785 lock USER
787 Temporarily suspend access to the user's home directory and remove
788 any associated cryptographic keys from memory. Any attempts to
789 access the user's home directory will stall until the home
790 directory is unlocked again (i.e. re-authenticated). This
791 functionality is primarily intended to be used during system
792 suspend to make sure the user's data cannot be accessed until the
793 user re-authenticates on resume. This operation is only defined for
794 home directories that use the LUKS2 storage mechanism.
795 unlock USER
797 Resume access to the user's home directory again, undoing the
798 effect of lock above. This requires authentication of the user, as
799 the cryptographic keys required for access to the home directory
800 need to be reacquired.
801 lock-all
803 Execute the lock command on all suitable home directories at once.
804 This operation is generally executed on system suspend (i.e. by
805 systemctl suspend and related commands), to ensure all active
806 user's cryptographic keys for accessing their home directories are
807 removed from memory.
808 deactivate-all
810 Execute the deactivate command on all active home directories at
811 once. This operation is generally executed on system shut down
812 (i.e. by systemctl poweroff and related commands), to ensure all
813 active user's home directories are fully deactivated before /home/
814 and related file systems are unmounted.
815 with USER COMMAND...
817 Activate the specified user's home directory, run the specified
818 command (under the caller's identity, not the specified user's) and
819 deactivate the home directory afterwards again (unless the user is
820 logged in otherwise). This command is useful for running privileged
821 backup scripts and such, but requires authentication with the
822 user's credentials in order to be able to unlock the user's home
823 directory.
824 rebalance
826 Rebalance free disk space between active home areas and the backing
827 storage. See --rebalance-weight= above. This executes no operation
828 unless there's at least one active LUKS2 home area that has disk
829 space rebalancing enabled. This operation is synchronous: it will
830 only complete once disk space is rebalanced according to the
831 rebalancing weights. Note that rebalancing also takes place
832 automatically in the background in regular intervals. Use this
833 command to synchronously ensure disk space is properly
834 redistributed before initiating an operation requiring large
835 amounts of disk space.
836
838 On success, 0 is returned, a non-zero failure code otherwise.
839 When a command is invoked with with, the exit status of the child is
841 propagated. Effectively, homectl will exit without error if the command
842 is successfully invoked and finishes successfully.
843
845 $SYSTEMD_LOG_LEVEL
846 The maximum log level of emitted messages (messages with a higher
847 log level, i.e. less important ones, will be suppressed). Either
848 one of (in order of decreasing importance) emerg, alert, crit, err,
849 warning, notice, info, debug, or an integer in the range 0...7. See
850 syslog(3) for more information.
851 $SYSTEMD_LOG_COLOR
853 A boolean. If true, messages written to the tty will be colored
854 according to priority.
855 This setting is only useful when messages are written directly to
857 the terminal, because journalctl(1) and other tools that display
858 logs will color messages based on the log level on their own.
859 $SYSTEMD_LOG_TIME
861 A boolean. If true, console log messages will be prefixed with a
862 timestamp.
863 This setting is only useful when messages are written directly to
865 the terminal or a file, because journalctl(1) and other tools that
866 display logs will attach timestamps based on the entry metadata on
867 their own.
868 $SYSTEMD_LOG_LOCATION
870 A boolean. If true, messages will be prefixed with a filename and
871 line number in the source code where the message originates.
872 Note that the log location is often attached as metadata to journal
874 entries anyway. Including it directly in the message text can
875 nevertheless be convenient when debugging programs.
876 $SYSTEMD_LOG_TID
878 A boolean. If true, messages will be prefixed with the current
879 numerical thread ID (TID).
880 Note that the this information is attached as metadata to journal
882 entries anyway. Including it directly in the message text can
883 nevertheless be convenient when debugging programs.
884 $SYSTEMD_LOG_TARGET
886 The destination for log messages. One of console (log to the
887 attached tty), console-prefixed (log to the attached tty but with
888 prefixes encoding the log level and "facility", see syslog(3), kmsg
889 (log to the kernel circular log buffer), journal (log to the
890 journal), journal-or-kmsg (log to the journal if available, and to
891 kmsg otherwise), auto (determine the appropriate log target
892 automatically, the default), null (disable log output).
893 $SYSTEMD_PAGER
895 Pager to use when --no-pager is not given; overrides $PAGER. If
896 neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
897 pager implementations are tried in turn, including less(1) and
898 more(1), until one is found. If no pager implementation is
899 discovered no pager is invoked. Setting this environment variable
900 to an empty string or the value "cat" is equivalent to passing
901 --no-pager.
902 Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER (as well
904 as $PAGER) will be silently ignored.
905 $SYSTEMD_LESS
907 Override the options passed to less (by default "FRSXMK").
908 Users might want to change two options in particular:
910 K
912 This option instructs the pager to exit immediately when Ctrl+C
913 is pressed. To allow less to handle Ctrl+C itself to switch
914 back to the pager command prompt, unset this option.
915 If the value of $SYSTEMD_LESS does not include "K", and the
917 pager that is invoked is less, Ctrl+C will be ignored by the
918 executable, and needs to be handled by the pager.
919 X
921 This option instructs the pager to not send termcap
922 initialization and deinitialization strings to the terminal. It
923 is set by default to allow command output to remain visible in
924 the terminal even after the pager exits. Nevertheless, this
925 prevents some pager functionality from working, in particular
926 paged output cannot be scrolled with the mouse.
927 See less(1) for more discussion.
929 $SYSTEMD_LESSCHARSET
931 Override the charset passed to less (by default "utf-8", if the
932 invoking terminal is determined to be UTF-8 compatible).
933 $SYSTEMD_PAGERSECURE
935 Takes a boolean argument. When true, the "secure" mode of the pager
936 is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
937 at all, secure mode is enabled if the effective UID is not the same
938 as the owner of the login session, see geteuid(2) and
939 sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
940 when invoking the pager, and the pager shall disable commands that
941 open or create new files or start new subprocesses. When
942 $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
943 to implement secure mode will not be used. (Currently only less(1)
944 implements secure mode.)
945 Note: when commands are invoked with elevated privileges, for
947 example under sudo(8) or pkexec(1), care must be taken to ensure
948 that unintended interactive features are not enabled. "Secure" mode
949 for the pager may be enabled automatically as describe above.
950 Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
951 environment allows the user to invoke arbitrary commands. Note that
952 if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
953 $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
954 completely disable the pager using --no-pager instead.
955 $SYSTEMD_COLORS
957 Takes a boolean argument. When true, systemd and related utilities
958 will use colors in their output, otherwise the output will be
959 monochrome. Additionally, the variable can take one of the
960 following special values: "16", "256" to restrict the use of colors
961 to the base 16 or 256 ANSI colors, respectively. This can be
962 specified to override the automatic decision based on $TERM and
963 what the console is connected to.
964 $SYSTEMD_URLIFY
966 The value must be a boolean. Controls whether clickable links
967 should be generated in the output for terminal emulators supporting
968 this. This can be specified to override the decision that systemd
969 makes based on $TERM and other conditions.
970
972 Example 1. Create a user "waldo" in the administrator group "wheel",
973 and assign 500 MiB disk space to them.
974 homectl create waldo --real-name="Waldo McWaldo" -G wheel --disk-size=500M
976 Example 2. Create a user "wally" on a USB stick, and assign a maximum
978 of 500 concurrent tasks to them.
979 homectl create wally --real-name="Wally McWally" --image-path=/dev/disk/by-id/usb-SanDisk_Ultra_Fit_476fff954b2b5c44-0:0 --tasks-max=500
981 Example 3. Change nice level of user "odlaw" to +5 and make sure the
983 environment variable $SOME is set to the string "THING" for them on
984 login.
985 homectl update odlaw --nice=5 --setenv=SOME=THING
987 Example 4. Set up authentication with a YubiKey security token using
989 PKCS#11/PIV:
990 # Clear the Yubikey from any old keys (careful!)
992 ykman piv reset
993 # Generate a new private/public key pair on the device, store the public key in 'pubkey.pem'.
995 ykman piv generate-key -a RSA2048 9d pubkey.pem
996 # Create a self-signed certificate from this public key, and store it on the device.
998 ykman piv generate-certificate --subject "Knobelei" 9d pubkey.pem
999 # We don't need the public key on disk anymore
1001 rm pubkey.pem
1002 # Allow the security token to unlock the account of user 'lafcadio'.
1004 homectl update lafcadio --pkcs11-token-uri=auto
1005 Example 5. Set up authentication with a FIDO2 security token:
1007 # Allow a FIDO2 security token to unlock the account of user 'nihilbaxter'.
1009 homectl update nihilbaxter --fido2-device=auto
1010
1012 systemd(1), systemd-homed.service(8), homed.conf(5), userdbctl(1),
1013 useradd(8), cryptsetup(8)
1014
1016 1. JSON User Records
1017 https://systemd.io/USER_RECORD
1018 2. Icon Naming Specification
1020 https://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html
1021 3. User/Group Name Syntax
1023 https://systemd.io/USER_NAMES
1024systemd 253 HOMECTL(1)