Provided by: systemd-homed_255.4-1ubuntu8.10_amd64 

NAME
systemd-homed.service, systemd-homed - Home Area/User Account Manager
SYNOPSIS
systemd-homed.service
/usr/lib/systemd/systemd-homed
DESCRIPTION
systemd-homed is a system service that may be used to create, remove, change or inspect home areas
(directories and network mounts and real or loopback block devices with a filesystem, optionally
encrypted).
Most of systemd-homed's functionality is accessible through the homectl(1) command.
See the Home Directories[1] documentation for details about the format and design of home areas managed
by systemd-homed.service.
Each home directory managed by systemd-homed.service synthesizes a local user and group. These are made
available to the system using the User/Group Record Lookup API via Varlink[2], and thus may be browsed
with userdbctl(1).
KEY MANAGEMENT
User records are cryptographically signed with a public/private key pair (the signature is part of the
JSON record itself). For a user to be permitted to log in locally the public key matching the signature
of their user record must be installed. For a user record to be modified locally the private key matching
the signature must be installed locally, too. The keys are stored in the /var/lib/systemd/home/
directory:
/var/lib/systemd/home/local.private
The private key of the public/private key pair used for local records. Currently, only a single such
key may be installed.
Added in version 246.
/var/lib/systemd/home/local.public
The public key of the public/private key pair used for local records. Currently, only a single such
key may be installed.
Added in version 246.
/var/lib/systemd/home/*.public
Additional public keys. Any users whose user records are signed with any of these keys are permitted
to log in locally. An arbitrary number of keys may be installed this way.
Added in version 246.
All key files listed above are in PEM format.
In order to migrate a home directory from a host "foobar" to another host "quux" it is hence sufficient
to copy /var/lib/systemd/home/local.public from the host "foobar" to "quux", maybe calling the file on
the destination /var/lib/systemd/home/foobar.public, reflecting the origin of the key. If the user record
should be modifiable on "quux" the pair /var/lib/systemd/home/local.public and
/var/lib/systemd/home/local.private need to be copied from "foobar" to "quux", and placed under the
identical paths there, as currently only a single private key is supported per host. Note of course that
the latter means that user records generated/signed before the key pair is copied in, lose their
validity.
SEE ALSO
systemd(1), homed.conf(5), homectl(1), pam_systemd_home(8), userdbctl(1), org.freedesktop.home1(5)
NOTES
1. Home Directories
https://systemd.io/HOME_DIRECTORY
2. User/Group Record Lookup API via Varlink
https://systemd.io/USER_GROUP_API
systemd 255 SYSTEMD-HOMED.SERVICE(8)