SYSTEMD-USERDBD.SERVICE(8) systemd-userdbd.serviceSYSTEMD-USERDBD.SERVICE(8)
systemd-userdbd.service, systemd-userdbd - JSON User/Group Record
Query Multiplexer/NSS Compatibility
systemd-userdbd.service
/usr/lib/systemd/systemd-userdbd
systemd-userdbd is a system service that multiplexes user/group
lookups to all local services that provide JSON user/group record
definitions to the system. In addition it synthesizes JSON user/group
records from classic UNIX/glibc NSS user/group records in order to
provide full backwards compatibility.
Most of systemd-userdbd's functionality is accessible through the
userdbctl(1) command.
The user and group records this service provides access to follow the
JSON User Record[1] and JSON Group Record[2] definitions. This
service implements the User/Group Record Lookup API via Varlink[3],
and multiplexes access other services implementing this API, too. It
is thus both server and client of this API.
This service provides two distinct Varlink[4] services:
io.systemd.Multiplexer provides a single, unified API for querying
JSON user and group records. Internally it talks to all other
user/group record services running on the system in parallel and
forwards any information discovered. This simplifies clients
substantially since they need to talk to a single service only
instead of all of them in parallel. io.systemd.NameSeviceSwitch
provides compatibility with classic UNIX/glibc NSS user records, i.e.
converts struct passwd and struct group records as acquired with APIs
such as getpwnam(1) to JSON user/group records, thus hiding the
differences between the services as much as possible.
systemd(1), nss-systemd(8), userdbctl(1), systemd-homed.service(8)
1. JSON User Record
https://systemd.io/USER_RECORD
2. JSON Group Record
https://systemd.io/GROUP_RECORD
3. User/Group Record Lookup API via Varlink
https://systemd.io/USER_GROUP_API
4. Varlink
https://varlink.org/
This page is part of the systemd (systemd system and service manager)
project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have a bug
report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩. This
page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2020-08-13. (At that
time, the date of the most recent commit that was found in the repos‐
itory was 2020-08-11.) If you discover any rendering problems in
this HTML version of the page, or you believe there is a better or
more up-to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not part
of the original manual page), send a mail to man-pages@man7.org
systemd 246 SYSTEMD-USERDBD.SERVICE(8)
Pages that refer to this page: 30-systemd-environment-d-generator(7) , systemd.index(7)