NAME
homectl - Create, remove, change or inspect home directoriesSYNOPSIS
homectl
[OPTIONS...] {COMMAND} [NAME...]
DESCRIPTION
homectl may be used to create, remove, change or inspect a user's home directory. It's primarily a command interfacing with systemd-homed.service(8) which manages home directories of users. Home directories managed by systemd-homed.service are self-contained, and thus include the user's full metadata record in the home's data storage itself, making them easy to migrate between machines. In particular, a home directory describes a matching user record, and every user record managed by systemd-homed.service also implies existence and encapsulation of a home directory. The user account and home directory become the same concept. The following backing storage mechanisms are supported:•An individual LUKS2 encrypted loopback
file for a user, stored in /home/*.home. At login the file system contained in
this files is mounted, after the LUKS2 encrypted volume has been attached. The
user's password is identical to the encryption passphrase of the LUKS2 volume.
Access to data without preceding user authentication is thus not possible,
even for the system administrator. This storage mechanism provides the
strongest data security and is thus recommended.
•Similar, but the LUKS2 encrypted file
system is located on regular block device, such as an USB storage stick. In
this mode home directories and all data they include are nicely migratable
between machines, simply by plugging the USB stick into different systems at
different times.
•An encrypted directory using
"fscrypt" on file systems that support it (at the moment this is
primarily "ext4"), located in /home/*.homedir. This mechanism also
provides encryption, but substantially weaker than LUKS2, as most file system
metadata is unprotected. Moreover it currently does not support changing user
passwords once the home directory has been created.
•A "btrfs" subvolume for each
user, also located in /home/*.homedir. This provides no encryption, but good
quota support.
•A regular directory for each user,
also located in /home/*.homedir. This provides no encryption, but is a
suitable fallback available on all machines, even where LUKS2,
"fscrypt" or "btrfs" support is not available.
•An individual Windows file share
(CIFS) for each user.
Note that systemd-homed.service and homectl will not manage
"classic" UNIX user accounts as created with useradd(8) or
similar tools. In particular, this functionality is not suitable for managing
system users (i.e. users with a UID below 1000) but is exclusive to regular
("human") users.
Note that users/home directories managed via systemd-homed.service do not
show up in /etc/passwd and similar files, they are synthesized via glibc NSS
during runtime. They are thus resolvable and may be enumerated via the
getent(1) tool.
This tool interfaces directly with systemd-homed.service, and may execute
specific commands on the home directories it manages. Since every home
directory managed that way also defines a JSON user and group record these
home directories may also be inspected and enumerated via userdbctl(1).
Home directories managed by systemd-homed.service are usually in one of two
states, or in a transition state between them: when "active" they
are unlocked and mounted, and thus accessible to the system and its programs;
when "inactive" they are not mounted and thus not accessible.
Activation happens automatically at login of the user and usually can only
complete after a password (or other authentication token) has been supplied.
Deactivation happens after the user fully logged out. A home directory remains
active as long as the user is logged in at least once, i.e. has at least one
login session. When the user logs in a second time simultaneously the home
directory remains active. It is deactivated only after the last of the user's
sessions ends.
OPTIONS
The following general options are understood (further options that control the various properties of user records managed by systemd-homed.service are documented further down): --identity=FILERead the user's JSON record from the specified
file. If passed as "-" read the user record from standard input. The
supplied JSON object must follow the structure documented in JSON User
Records[1]. This option may be used in conjunction with the create
and update commands (see below), where it allows configuring the user
record in JSON as-is, instead of setting the individual user record properties
(see below).
--json=FORMAT, -j
Controls whether to output the user record in
JSON format, if the inspect command (see below) is used. Takes one of
"pretty", "short" or "off". If
"pretty" human-friendly whitespace and newlines are inserted in the
output to make the JSON data more readable. If "short" all
superfluous whitespace is suppressed. If "off" (the default) the
user information is not shown in JSON format but in a friendly human readable
formatting instead. The -j option picks "pretty" when run
interactively and "short" otherwise.
--export-format=FORMAT, -E, -EE
When used with the inspect verb in JSON
mode (see above) may be used to suppress certain aspects of the JSON user
record on output. Specifically, if "stripped" format is used the
binding and runtime fields of the record are removed. If "minimal"
format is used the cryptographic signature is removed too. If "full"
format is used the full JSON record is shown (this is the default). This
option is useful for copying an existing user record to a different system in
order to create a similar user there with the same settings. Specifically:
homectl inspect -EE | ssh root@othersystem homectl create -i- may be
used as simple command line for replicating a user on another host. -E
is equivalent to -j --export-format=stripped, -EE to -j
--export-format=minimal. Note that when replicating user accounts user
records acquired in "stripped" mode will retain the original
cryptographic signatures and thus may only be modified when the private key to
update them is available on the destination machine. When replicating users in
"minimal" mode, the signature is removed during the replication and
thus the record will be implicitly signed with the key of the destination
machine and may be updated there without any private key replication.
-H, --host=
Execute the operation remotely. Specify a
hostname, or a username and hostname separated by "@", to connect
to. The hostname may optionally be suffixed by a port ssh is listening on,
separated by ":", and then a container name, separated by
"/", which connects directly to a specific container on the
specified host. This will use SSH to talk to the remote machine manager
instance. Container names may be enumerated with machinectl -H
HOST. Put IPv6 addresses in brackets.
-M, --machine=
Execute operation on a local container.
Specify a container name to connect to, optionally prefixed by a user name to
connect as and a separating "@" character. If the special string
".host" is used in place of the container name, a connection to the
local system is made (which is useful to connect to a specific user's user
bus: "--user --machine=[email protected]"). If the "@" syntax
is not used, the connection is made as root user. If the "@" syntax
is used either the left hand side or the right hand side may be omitted (but
not both) in which case the local user name and ".host" are
implied.
--no-pager
Do not pipe output into a pager.
--no-legend
Do not print the legend, i.e. column headers
and the footer with hints.
--no-ask-password
Do not query the user for authentication for
privileged operations.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
USER RECORD PROPERTIES
The following options control various properties of the user records/home directories that systemd-homed.service manages. These switches may be used in conjunction with the create and update commands for configuring various aspects of the home directory and the user account: --real-name=NAME, -c NAMEThe real name for the user. This corresponds
with the GECOS field on classic UNIX NSS records.
--realm=REALM
The realm for the user. The realm associates a
user with a specific organization or installation, and allows distinguishing
users of the same name defined in different contexts. The realm can be any
string that also qualifies as valid DNS domain name, and it is recommended to
use the organization's or installation's domain name for this purpose, but
this is not enforced nor required. On each system only a single user of the
same name may exist, and if a user with the same name and realm is seen it is
assumed to refer to the same user while a user with the same name but
different realm is considered a different user. Note that this means that two
users sharing the same name but with distinct realms are not allowed on the
same system. Assigning a realm to a user is optional.
--email-address=EMAIL
Takes an electronic mail address to associate
with the user. On log-in the $EMAIL environment variable is initialized
from this value.
--location=TEXT
Takes location specification for this user.
This is free-form text, which might or might not be usable by geo-location
applications. Example: --location="Berlin, Germany" or
--location="Basement, Room 3a"
--icon-name=ICON
Takes an icon name to associate with the user,
following the scheme defined by the Icon Naming Specification[2].
--home-dir=PATH, -dPATH
Takes a path to use as home directory for the
user. Note that this is the directory the user's home directory is mounted to
while the user is logged in. This is not where the user's data is actually
stored, see --image-path= for that. If not specified defaults to
/home/$USER.
--uid=UID
Takes a preferred numeric UNIX UID to assign
this user. If a user is to be created with the specified UID and it is already
taken by a different user on the local system then creation of the home
directory is refused. Note though, if after creating the home directory it is
used on a different system and the configured UID is taken by another user
there, then systemd-homed may assign the user a different UID on that
system. The specified UID must be outside of the system user range. It is
recommended to use the 60001...60513 UID range for this purpose. If not
specified, the UID is automatically picked. If the home directory is found to
be owned by a different UID when logging in, the home directory and everything
underneath it will have its ownership changed automatically before login
completes.
Note that changing this option for existing home directories generally has no
effect on home directories that already have been registered locally (have a
local binding), as the UID used for an account on the local system is
determined when the home directory is first activated on it, and then remains
in effect until the home directory is removed.
Note that users managed by systemd-homed always have a matching group
associated with the same name as well as a GID matching the UID of the user.
Thus, configuring the GID separately is not permitted.
--member-of=GROUP, -G GROUP
Takes a comma-separated list of auxiliary UNIX
groups this user shall belong to. Example: --member-of=wheel to provide
the user with administrator privileges. Note that systemd-homed does
not manage any groups besides a group matching the user in name and numeric
UID/GID. Thus any groups listed here must be registered independently, for
example with groupadd(8). Any non-existent groups are ignored. This
option may be used more than once, in which case all specified group lists are
combined. If the user is currently a member of a group which is not listed,
the user will be removed from the group.
--skel=PATH
Takes a file system path to a directory.
Specifies the skeleton directory to initialize the home directory with. All
files and directories in the specified path are copied into any newly create
home directory. If not specified defaults to /etc/skel/.
--shell=SHELL
Takes a file system path. Specifies the shell
binary to execute on terminal logins. If not specified defaults to
/bin/bash.
--setenv=VARIABLE[=VALUE]
Takes an environment variable assignment to
set for all user processes. May be used multiple times to set multiple
environment variables. When "=" and VALUE are omitted, the
value of the variable with the same name in the program environment will be
used.
Note that a number of other settings also result in environment variables to be
set for the user, including --email=, --timezone= and
--language=.
--timezone=TIMEZONE
Takes a time zone location name that sets the
timezone for the specified user. When the user logs in the $TZ
environment variable is initialized from this setting. Example:
--timezone=Europe/Amsterdam will result in the environment variable
"TZ=:Europe/Amsterdam". (":" is used intentionally as part
of the timezone specification, see tzset(3).)
--language=LANG
Takes a specifier indicating the preferred
language of the user. The $LANG environment variable is initialized
from this value on login, and thus a value suitable for this environment
variable is accepted here, for example --language=de_DE.UTF8.
--ssh-authorized-keys=KEYS
Either takes a SSH authorized key line to
associate with the user record or a "@" character followed by a path
to a file to read one or more such lines from. SSH keys configured this way
are made available to SSH to permit access to this home directory and user
record. This option may be used more than once to configure multiple SSH
keys.
--pkcs11-token-uri=URI
Takes an RFC 7512 PKCS#11 URI referencing a
security token (e.g. YubiKey or PIV smartcard) that shall be able to unlock
the user account. The security token URI should reference a security token
with exactly one pair of X.509 certificate and private key. A random secret
key is then generated, encrypted with the public key of the X.509 certificate,
and stored as part of the user record. At login time it is decrypted with the
PKCS#11 module and then used to unlock the account and associated resources.
See below for an example how to set up authentication with a security token.
Instead of a valid PKCS#11 URI, the special strings "list" and
"auto" may be specified. If "list" is passed, a brief
table of suitable, currently plugged in PKCS#11 hardware tokens is shown,
along with their URIs. If "auto" is passed, a suitable PKCS#11
hardware token is automatically selected (this operation will fail if there
isn't exactly one suitable token discovered). The latter is a useful shortcut
for the most common case where a single PKCS#11 hardware token is plugged in.
Note that many hardware security tokens implement both PKCS#11/PIV and FIDO2
with the "hmac-secret" extension (for example: the YubiKey 5
series), as supported with the --fido2-device= option below. Both
mechanisms are similarly powerful, though FIDO2 is the more modern technology.
PKCS#11/PIV tokens have the benefit of being recognizable before
authentication and hence can be used for implying the user identity to use for
logging in, which FIDO2 does not allow. PKCS#11/PIV devices generally require
initialization (i.e. storing a private/public key pair on them, see example
below) before they can be used; FIDO2 security tokens generally do not
required that, and work out of the box.
--fido2-credential-algorithm=STRING
Specify COSE algorithm used in credential
generation. The default value is "es256". Supported values are
"es256", "rs256" and "eddsa".
"es256" denotes ECDSA over NIST P-256 with SHA-256. "rs256"
denotes 2048-bit RSA with PKCS#1.5 padding and SHA-256. "eddsa"
denotes EDDSA over Curve25519 with SHA-512.
Note that your authenticator may not support some algorithms.
--fido2-device=PATH
Takes a path to a Linux "hidraw"
device (e.g. /dev/hidraw1), referring to a FIDO2 security token implementing
the "hmac-secret" extension that shall be able to unlock the user
account. A random salt value is generated on the host and passed to the FIDO2
device, which calculates a HMAC hash of the salt using an internal secret key.
The result is then used as the key to unlock the user account. The random salt
is included in the user record, so that whenever authentication is needed it
can be passed to the FIDO2 token again.
Instead of a valid path to a FIDO2 "hidraw" device the special strings
"list" and "auto" may be specified. If "list" is
passed, a brief table of suitable discovered FIDO2 devices is shown. If
"auto" is passed, a suitable FIDO2 token is automatically selected,
if exactly one is discovered. The latter is a useful shortcut for the most
common case where a single FIDO2 hardware token is plugged in.
Note that FIDO2 devices suitable for this option must implement the
"hmac-secret" extension. Most current devices (such as the YubiKey 5
series) do. If the extension is not implemented the device cannot be used for
unlocking home directories.
The FIDO2 device may be subsequently removed by setting the device path to an
empty string (e.g. homectl update $USER --fido2-device="").
Note that many hardware security tokens implement both FIDO2 and PKCS#11/PIV
(and thus may be used with either --fido2-device= or
--pkcs11-token-uri=), for a discussion see above.
--fido2-with-client-pin=BOOL
When enrolling a FIDO2 security token,
controls whether to require the user to enter a PIN when unlocking the account
(the FIDO2 "clientPin" feature). Defaults to "yes". (Note:
this setting is without effect if the security token does not support the
"clientPin" feature at all, or does not allow enabling or disabling
it.)
--fido2-with-user-presence=BOOL
When enrolling a FIDO2 security token,
controls whether to require the user to verify presence (tap the token, the
FIDO2 "up" feature) when unlocking the account. Defaults to
"yes". (Note: this setting is without effect if the security token
does not support the "up" feature at all, or does not allow enabling
or disabling it.)
--fido2-with-user-verification=BOOL
When enrolling a FIDO2 security token,
controls whether to require user verification when unlocking the account (the
FIDO2 "uv" feature). Defaults to "no". (Note: this setting
is without effect if the security token does not support the "uv"
feature at all, or does not allow enabling or disabling it.)
--recovery-key=BOOL
Accepts a boolean argument. If enabled a
recovery key is configured for the account. A recovery key is a computer
generated access key that may be used to regain access to an account if the
password has been forgotten or the authentication token lost. The key is
generated and shown on screen, and should be printed or otherwise transferred
to a secure location. A recovery key may be entered instead of a regular
password to unlock the account.
--locked=BOOLEAN
Takes a boolean argument. Specifies whether
this user account shall be locked. If true logins into this account are
prohibited, if false (the default) they are permitted (of course, only if
authorization otherwise succeeds).
--not-before=TIMESTAMP, --not-after=TIMESTAMP
These options take a timestamp string, in the
format documented in systemd.time(7) and configures points in time
before and after logins into this account are not permitted.
--rate-limit-interval=SECS,
--rate-limit-burst=NUMBER
Configures a rate limit on authentication
attempts for this user. If the user attempts to authenticate more often than
the specified number, on a specific system, within the specified time interval
authentication is refused until the time interval passes. Defaults to 10 times
per 1min.
--password-hint=TEXT
Takes a password hint to store alongside the
user record. This string is stored accessible only to privileged users and the
user itself and may not be queried by other users. Example:
--password-hint="My first pet's name".
--enforce-password-policy=BOOL, -P
Takes a boolean argument. Configures whether
to enforce the system's password policy for this user, regarding quality and
strength of selected passwords. Defaults to on. -P is short for
---enforce-password-policy=no.
--password-change-now=BOOL
Takes a boolean argument. If true the user is
asked to change their password on next login.
--password-change-min=TIME,
--password-change-max=TIME,
--password-change-warn=TIME,
--password-change-inactive=TIME
Each of these options takes a time span
specification as argument (in the syntax documented in systemd.time(7))
and configures various aspects of the user's password expiration policy.
Specifically, --password-change-min= configures how much time has to
pass after changing the password of the user until the password may be changed
again. If the user tries to change their password before this time passes the
attempt is refused. --password-change-max= configures how soon after it
has been changed the password expires and needs to be changed again. After
this time passes logging in may only proceed after the password is changed.
--password-change-warn= specifies how much earlier than then the time
configured with --password-change-max= the user is warned at login to
change their password as it will expire soon. Finally
--password-change-inactive= configures the time which has to pass after
the password as expired until the user is not permitted to log in or change
the password anymore. Note that these options only apply to password
authentication, and do not apply to other forms of authentication, for example
PKCS#11-based security token authentication.
--disk-size=BYTES
Either takes a size in bytes as argument
(possibly using the usual K, M, G, ... suffixes for 1024 base values), a
percentage value, or the special strings "min" or "max",
and configures the disk space to assign to the user. If a percentage value is
specified (i.e. the argument suffixed with "%") it is taken relative
to the available disk space of the backing file system. If specified as
"min" assigns the minimal disk space permitted by the constraints of
the backing file system and other limits, when specified as "max"
assigns the maximum disk space available. If the LUKS2 backend is used this
configures the size of the loopback file and file system contained therein.
For the other storage backends configures disk quota using the filesystem's
native quota logic, if available. If not specified, defaults to 85% of the
available disk space for the LUKS2 backend and to no quota for the
others.
--access-mode=MODE
Takes a UNIX file access mode written in
octal. Configures the access mode of the home directory itself. Note that this
is only used when the directory is first created, and the user may change this
any time afterwards. Example: --access-mode=0700
--umask=MASK
Takes the access mode mask (in octal syntax)
to apply to newly created files and directories of the user
("umask"). If set this controls the initial umask set for all login
sessions of the user, possibly overriding the system's defaults.
--nice=NICE
Takes the numeric scheduling priority
("nice level") to apply to the processes of the user at login time.
Takes a numeric value in the range -20 (highest priority) to 19 (lowest
priority).
--rlimit=LIMIT=VALUE[:VALUE]
Allows configuration of resource limits for
processes of this user, see getrlimit(2) for details. Takes a resource
limit name (e.g. "LIMIT_NOFILE") followed by an equal sign, followed
by a numeric limit. Optionally, separated by colon a second numeric limit may
be specified. If two are specified this refers to the soft and hard limits,
respectively. If only one limit is specified the setting sets both limits in
one.
--tasks-max=TASKS
Takes a non-zero unsigned integer as argument.
Configures the maximum number of tasks (i.e. threads, where each process is at
least one thread) the user may have at any given time. This limit applies to
all tasks forked off the user's sessions, even if they change user identity
via su(1) or a similar tool. Use --rlimit=LIMIT_NPROC= to place
a limit on the tasks actually running under the UID of the user, thus
excluding any child processes that might have changed user identity. This
controls the TasksMax= setting of the per-user systemd slice unit
user-$UID.slice. See systemd.resource-control(5) for further
details.
--memory-high=BYTES, --memory-max=BYTES
Set a limit on the memory a user may take up
on a system at any given time in bytes (the usual K, M, G, ... suffixes are
supported, to the base of 1024). This includes all memory used by the user
itself and all processes they forked off that changed user credentials. This
controls the MemoryHigh= and MemoryMax= settings of the per-user
systemd slice unit user-$UID.slice. See systemd.resource-control(5) for
further details.
--cpu-weight=WEIGHT, --io-weight=WEIGHT
Set CPU and IO scheduling weights of the
processes of the user, including those of processes forked off by the user
that changed user credentials. Takes a numeric value in the range 1...10000.
This controls the CPUWeight= and IOWeight= settings of the
per-user systemd slice unit user-$UID.slice. See
systemd.resource-control(5) for further details.
--storage=STORAGE
Selects the storage mechanism to use for this
home directory. Takes one of "luks", "fscrypt",
"directory", "subvolume", "cifs". For details
about these mechanisms, see above. If a new home directory is created and the
storage type is not specifically specified, homed.conf(5) defines which
default storage to use.
--image-path=PATH
Takes a file system path. Configures where to
place the user's home directory. When LUKS2 storage is used refers to the path
to the loopback file, otherwise to the path to the home directory (which may
be in /home/ or any other accessible filesystem). When unspecified defaults to
/home/$USER.home when LUKS storage is used and /home/$USER.homedir for the
other storage mechanisms. Not defined for the "cifs" storage
mechanism. To use LUKS2 storage on a regular block device (for example a USB
stick) pass the path to the block device here. Specifying the path to a
directory here when using LUKS2 storage is not allowed. Similar, specifying
the path to a regular file or device node is not allowed if any of the other
storage backends are used.
--drop-caches=BOOL
Automatically flush OS file system caches on
logout. This is useful in combination with the fscrypt storage backend to
ensure the OS does not keep decrypted versions of the files and directories in
memory (and accessible) after logout. This option is also supported on other
backends, but should not bring any benefit there. Defaults to off, except if
the selected storage backend is fscrypt, where it defaults to on. Note that
flushing OS caches will negatively influence performance of the OS shortly
after logout.
--fs-type=TYPE
When LUKS2 storage is used configures the file
system type to use inside the home directory LUKS2 container. One of
"btrfs", "ext4", "xfs". If not specified
homed.conf(5) defines which default file system type to use. Note that
"xfs" is not recommended as its support for file system resizing is
too limited.
--luks-discard=BOOL
When LUKS2 storage is used configures whether
to enable the "discard" feature of the file system. If enabled the
file system on top of the LUKS2 volume will report empty block information to
LUKS2 and the loopback file below, ensuring that empty space in the home
directory is returned to the backing file system below the LUKS2 volume,
resulting in a "sparse" loopback file. This option mostly defaults
to off, since this permits over-committing home directories which results in
I/O errors if the underlying file system runs full while the upper file system
wants to allocate a block. Such I/O errors are generally not handled well by
file systems nor applications. When LUKS2 storage is used on top of regular
block devices (instead of on top a loopback file) the discard logic defaults
to on.
--luks-offline-discard=BOOL
Similar to --luks-discard=, controls
the trimming of the file system. However, while --luks-discard=
controls what happens when the home directory is active,
--luks-offline-discard= controls what happens when it becomes inactive,
i.e. whether to trim/allocate the storage when deactivating the home
directory. This option defaults to on, to ensure disk space is minimized while
a user is not logged in.
--luks-extra-mount-options=OPTIONS
Takes a string containing additional mount
options to use when mounting the LUKS volume. If specified, this string will
be appended to the default, built-in mount options.
--luks-cipher=CIPHER, --luks-cipher-mode=MODE,
--luks-volume-key-size= BYTES,
--luks-pbkdf-type=TYPE,
--luks-pbkdf-hash-algorithm=ALGORITHM,
--luks-pbkdf-time-cost= SECONDS,
--luks-pbkdf-memory-cost= BYTES,
--luks-pbkdf-parallel-threads= THREADS,
--luks-sector-size= BYTES
Configures various cryptographic parameters
for the LUKS2 storage mechanism. See cryptsetup(8) for details on the
specific attributes.
Note that homectl uses bytes for key size, like /proc/crypto, but
cryptsetup(8) uses bits.
--auto-resize-mode=
Configures whether to automatically grow
and/or shrink the backing file system on login and logout. Takes one of the
strings "off", "grow", "shrink-and-grow". Only
applies to the LUKS2 backend currently, and if the btrfs file system is used
inside it (since only then online growing/shrinking of the file system is
supported). Defaults to "shrink-and-grow", if LUKS2/btrfs is used,
otherwise is off. If set to "off" no automatic shrinking/growing
during login or logout is done. If set to "grow" the home area is
grown to the size configured via --disk-size= should it currently be
smaller. If it already matches the configured size or is larger no operation
is executed. If set to "shrink-and-grow" the home area is also
resized during logout to the minimal size the used disk space and file system
constraints permit. This mode thus ensures that while a home area is activated
it is sized to the configured size, but while deactivated it is compacted
taking up only the minimal space possible. Note that if the system is powered
off abnormally or if the user otherwise not logged out cleanly the shrinking
operation will not take place, and the user has to re-login/logout again
before it is executed again.
--rebalance-weight=
Configures the weight parameter for the free
disk space rebalancing logic. Only applies to the LUKS2 backend (since for the
LUKS2 backend disk space is allocated from a per-user loopback file system
instead of immediately from a common pool like the other backends do it). In
regular intervals free disk space in the active home areas and their backing
storage is redistributed among them, taking the weight value configured here
into account. Expects an integer in the range 1...10000, or the special string
"off". If not specified defaults to 100. The weight is used to scale
free space made available to the home areas: a home area with a weight of 200
will get twice the free space as one with a weight of 100; a home area with a
weight of 50 will get half of that. The backing file system will be assigned
space for a weight of 20. If set to "off" no automatic free space
distribution is done for this home area. Note that resizing the home area
explicitly (with homectl resize see below) will implicitly turn off the
automatic rebalancing. To reenable the automatic rebalancing use
--rebalance-weight= with an empty parameter.
--nosuid=BOOL, --nodev=BOOL,
--noexec=BOOL
Configures the "nosuid",
"nodev" and "noexec" mount options for the home
directories. By default "nodev" and "nosuid" are on, while
"noexec" is off. For details about these mount options see
mount(8).
--cifs-domain=DOMAIN, --cifs-user-name=USER,
--cifs-service= SERVICE,
--cifs-extra-mount-options=OPTIONS
Configures the Windows File Sharing (CIFS)
domain and user to associate with the home directory/user account, as well as
the file share ("service") to mount as directory. The latter is used
when "cifs" storage is selected. The file share should be specified
in format "// host/share/directory/...". The
directory part is optional — if not specified the home directory will
be placed in the top-level directory of the share. The
--cifs-extra-mount-options= setting allows specifying additional mount
options when mounting the share, see mount.cifs(8) for details.
--stop-delay=SECS
Configures the time the per-user service
manager shall continue to run after the all sessions of the user ended. The
default is configured in logind.conf(5) (for home directories of LUKS2
storage located on removable media this defaults to 0 though). A longer time
makes sure quick, repetitive logins are more efficient as the user's service
manager doesn't have to be started every time.
--kill-processes=BOOL
Configures whether to kill all processes of
the user on logout. The default is configured in logind.conf(5).
--auto-login=BOOL
Takes a boolean argument. Configures whether
the graphical UI of the system should automatically log this user in if
possible. Defaults to off. If less or more than one user is marked this way
automatic login is disabled.
COMMANDS
The following commands are understood: listList all home directories (along with brief
details) currently managed by systemd-homed.service. This command is also
executed if none is specified on the command line. (Note that the list of
users shown by this command does not include users managed by other
subsystems, such as system users or any traditional users listed in
/etc/passwd.)
activate USER [USER...]
Activate one or more home directories. The
home directories of each listed user will be activated and made available
under their mount points (typically in /home/$USER). Note that any home
activated this way stays active indefinitely, until it is explicitly
deactivated again (with deactivate, see below), or the user logs in and
out again and it thus is deactivated due to the automatic
deactivation-on-logout logic.
Activation of a home directory involves various operations that depend on the
selected storage mechanism. If the LUKS2 mechanism is used, this generally
involves: inquiring the user for a password, setting up a loopback device,
validating and activating the LUKS2 volume, checking the file system, mounting
the file system, and potentially changing the ownership of all included files
to the correct UID/GID.
deactivate USER [USER...]
Deactivate one or more home directories. This
undoes the effect of activate.
inspect USER [USER...]
Show various details about the specified home
directories. This shows various information about the home directory and its
user account, including runtime data such as current state, disk use and
similar. Combine with --json= to show the detailed JSON user record
instead, possibly combined with --export-format= to suppress certain
aspects of the output.
authenticate USER [USER...]
Validate authentication credentials of a home
directory. This queries the caller for a password (or similar) and checks that
it correctly unlocks the home directory. This leaves the home directory in the
state it is in, i.e. it leaves the home directory in inactive state if it was
inactive before, and in active state if it was active before.
create USER, create --identity=PATH
[USER]
Create a new home directory/user account of
the specified name. Use the various user record property options (as
documented above) to control various aspects of the home directory and its
user accounts.
The specified user name should follow the strict syntax described on
User/Group Name Syntax[3].
remove USER
Remove a home directory/user account. This
will remove both the home directory's user record and the home directory
itself, and thus delete all files and directories owned by the user.
update USER, update --identity=PATH
[USER]
Update a home directory/user account. Use the
various user record property options (as documented above) to make changes to
the account, or alternatively provide a full, updated JSON user record via the
--identity= option.
Note that changes to user records not signed by a cryptographic private key
available locally are not permitted, unless --identity= is used with a
user record that is already correctly signed by a recognized private
key.
passwd USER
Change the password of the specified home
directory/user account.
resize USER BYTES
Change the disk space assigned to the
specified home directory. If the LUKS2 storage mechanism is used this will
automatically resize the loopback file and the file system contained within.
Note that if "ext4" is used inside of the LUKS2 volume, it is
necessary to deactivate the home directory before shrinking it (i.e the user
has to log out). Growing can be done while the home directory is active. If
"xfs" is used inside of the LUKS2 volume the home directory may not
be shrunk whatsoever. On all three of "ext4", "xfs" and
"btrfs" the home directory may be grown while the user is logged in,
and on the latter also shrunk while the user is logged in. If the
"subvolume", "directory", "fscrypt" storage
mechanisms are used, resizing will change file system quota. The size
parameter may make use of the usual suffixes B, K, M, G, T (to the base of
1024). The special strings "min" and "max" may be
specified in place of a numeric size value, for minimizing or maximizing disk
space assigned to the home area, taking constraints of the file system, disk
usage inside the home area and on the backing storage into account.
lock USER
Temporarily suspend access to the user's home
directory and remove any associated cryptographic keys from memory. Any
attempts to access the user's home directory will stall until the home
directory is unlocked again (i.e. re-authenticated). This functionality is
primarily intended to be used during system suspend to make sure the user's
data cannot be accessed until the user re-authenticates on resume. This
operation is only defined for home directories that use the LUKS2 storage
mechanism.
unlock USER
Resume access to the user's home directory
again, undoing the effect of lock above. This requires authentication
of the user, as the cryptographic keys required for access to the home
directory need to be reacquired.
lock-all
Execute the lock command on all
suitable home directories at once. This operation is generally executed on
system suspend (i.e. by systemctl suspend and related commands), to
ensure all active user's cryptographic keys for accessing their home
directories are removed from memory.
deactivate-all
Execute the deactivate command on all
active home directories at once. This operation is generally executed on
system shut down (i.e. by systemctl poweroff and related commands), to
ensure all active user's home directories are fully deactivated before /home/
and related file systems are unmounted.
with USER COMMAND...
Activate the specified user's home directory,
run the specified command (under the caller's identity, not the specified
user's) and deactivate the home directory afterwards again (unless the user is
logged in otherwise). This command is useful for running privileged backup
scripts and such, but requires authentication with the user's credentials in
order to be able to unlock the user's home directory.
rebalance
Rebalance free disk space between active home
areas and the backing storage. See --rebalance-weight= above. This
executes no operation unless there's at least one active LUKS2 home area that
has disk space rebalancing enabled. This operation is synchronous: it will
only complete once disk space is rebalanced according to the rebalancing
weights. Note that rebalancing also takes place automatically in the
background in regular intervals. Use this command to synchronously ensure disk
space is properly redistributed before initiating an operation requiring large
amounts of disk space.
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise. When a command is invoked with with, the exit status of the child is propagated. Effectively, homectl will exit without error if the command is successfully invoked and finishes successfully.ENVIRONMENT
$SYSTEMD_LOG_LEVELThe maximum log level of emitted messages
(messages with a higher log level, i.e. less important ones, will be
suppressed). Either one of (in order of decreasing importance) emerg,
alert, crit, err, warning, notice,
info, debug, or an integer in the range 0...7. See
syslog(3) for more information.
$SYSTEMD_LOG_COLOR
A boolean. If true, messages written to the
tty will be colored according to priority.
This setting is only useful when messages are written directly to the terminal,
because journalctl(1) and other tools that display logs will color
messages based on the log level on their own.
$SYSTEMD_LOG_TIME
A boolean. If true, console log messages will
be prefixed with a timestamp.
This setting is only useful when messages are written directly to the terminal
or a file, because journalctl(1) and other tools that display logs will
attach timestamps based on the entry metadata on their own.
$SYSTEMD_LOG_LOCATION
A boolean. If true, messages will be prefixed
with a filename and line number in the source code where the message
originates.
Note that the log location is often attached as metadata to journal entries
anyway. Including it directly in the message text can nevertheless be
convenient when debugging programs.
$SYSTEMD_LOG_TID
A boolean. If true, messages will be prefixed
with the current numerical thread ID (TID).
Note that the this information is attached as metadata to journal entries
anyway. Including it directly in the message text can nevertheless be
convenient when debugging programs.
$SYSTEMD_LOG_TARGET
The destination for log messages. One of
console (log to the attached tty), console-prefixed (log to the
attached tty but with prefixes encoding the log level and
"facility", see syslog(3), kmsg (log to the kernel
circular log buffer), journal (log to the journal),
journal-or-kmsg (log to the journal if available, and to kmsg
otherwise), auto (determine the appropriate log target automatically,
the default), null (disable log output).
$SYSTEMD_PAGER
Pager to use when --no-pager is not
given; overrides $PAGER. If neither $SYSTEMD_PAGER nor
$PAGER are set, a set of well-known pager implementations are tried in
turn, including less(1) and more(1), until one is found. If no
pager implementation is discovered no pager is invoked. Setting this
environment variable to an empty string or the value "cat" is
equivalent to passing --no-pager.
Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER (as well
as $PAGER) will be silently ignored.
$SYSTEMD_LESS
Override the options passed to less (by
default "FRSXMK").
Users might want to change two options in particular:
K
Note that setting the regular $LESS environment variable has no effect
for less invocations by systemd tools.
See less(1) for more discussion.
$SYSTEMD_LESSCHARSET
This option instructs the pager to exit
immediately when Ctrl+C is pressed. To allow less to handle Ctrl+C
itself to switch back to the pager command prompt, unset this option.
If the value of $SYSTEMD_LESS does not include "K", and the
pager that is invoked is less, Ctrl+C will be ignored by the
executable, and needs to be handled by the pager.
X
This option instructs the pager to not send
termcap initialization and deinitialization strings to the terminal. It is set
by default to allow command output to remain visible in the terminal even
after the pager exits. Nevertheless, this prevents some pager functionality
from working, in particular paged output cannot be scrolled with the
mouse.
Override the charset passed to less (by
default "utf-8", if the invoking terminal is determined to be UTF-8
compatible).
Note that setting the regular $LESSCHARSET environment variable has no
effect for less invocations by systemd tools.
$SYSTEMD_PAGERSECURE
Takes a boolean argument. When true, the
"secure" mode of the pager is enabled; if false, disabled. If
$SYSTEMD_PAGERSECURE is not set at all, secure mode is enabled if the
effective UID is not the same as the owner of the login session, see
geteuid(2) and sd_pid_get_owner_uid(3). In secure mode,
LESSSECURE=1 will be set when invoking the pager, and the pager shall
disable commands that open or create new files or start new subprocesses. When
$SYSTEMD_PAGERSECURE is not set at all, pagers which are not known to
implement secure mode will not be used. (Currently only less(1)
implements secure mode.)
Note: when commands are invoked with elevated privileges, for example under
sudo(8) or pkexec(1), care must be taken to ensure that
unintended interactive features are not enabled. "Secure" mode for
the pager may be enabled automatically as describe above. Setting
SYSTEMD_PAGERSECURE=0 or not removing it from the inherited environment
allows the user to invoke arbitrary commands. Note that if the
$SYSTEMD_PAGER or $PAGER variables are to be honoured,
$SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
completely disable the pager using --no-pager instead.
$SYSTEMD_COLORS
Takes a boolean argument. When true,
systemd and related utilities will use colors in their output,
otherwise the output will be monochrome. Additionally, the variable can take
one of the following special values: "16", "256" to
restrict the use of colors to the base 16 or 256 ANSI colors, respectively.
This can be specified to override the automatic decision based on $TERM
and what the console is connected to.
$SYSTEMD_URLIFY
The value must be a boolean. Controls whether
clickable links should be generated in the output for terminal emulators
supporting this. This can be specified to override the decision that
systemd makes based on $TERM and other conditions.
EXAMPLES
Example 1. Create a user "waldo" in the administrator group "wheel", and assign 500 MiB disk space to them.homectl create waldo --real-name="Waldo McWaldo" -G wheel --disk-size=500M
homectl create wally --real-name="Wally McWally" --image-path=/dev/disk/by-id/usb-SanDisk_Ultra_Fit_476fff954b2b5c44-0:0 --tasks-max=500
homectl update odlaw --nice=5 --setenv=SOME=THING
# Clear the Yubikey from any old keys (careful!) ykman piv reset # Generate a new private/public key pair on the device, store the public key in 'pubkey.pem'. ykman piv generate-key -a RSA2048 9d pubkey.pem # Create a self-signed certificate from this public key, and store it on the device. ykman piv generate-certificate --subject "Knobelei" 9d pubkey.pem # We don't need the public key on disk anymore rm pubkey.pem # Allow the security token to unlock the account of user 'lafcadio'. homectl update lafcadio --pkcs11-token-uri=auto
# Allow a FIDO2 security token to unlock the account of user 'nihilbaxter'. homectl update nihilbaxter --fido2-device=auto
SEE ALSO
systemd(1), systemd-homed.service(8), homed.conf(5), userdbctl(1), useradd(8), cryptsetup(8)NOTES
- 1.
- JSON User Records
- 2.
- Icon Naming Specification
- 3.
- User/Group Name Syntax
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