SYSTEMD-UDEVD.SERVICE(8) systemd-udevd.service SYSTEMD-UDEVD.SERVICE(8)
systemd-udevd.service, systemd-udevd-control.socket, systemd-udevd- kernel.socket, systemd-udevd - Device event managing daemon
systemd-udevd.service systemd-udevd-control.socket systemd-udevd-kernel.socket /usr/lib/systemd/systemd-udevd [--daemon] [--debug] [--children-max=] [--exec-delay=] [--event-timeout=] [--resolve-names=early|late|never] [--version] [--help]
systemd-udevd listens to kernel uevents. For every event, systemd-udevd executes matching instructions specified in udev rules. See udev(7). The behavior of the daemon can be configured using udev.conf(5), its command line options, environment variables, and on the kernel command line, or changed dynamically with udevadm control.
-d, --daemon Detach and run in the background. -D, --debug Print debug messages to standard error. -c=, --children-max= Limit the number of events executed in parallel. -e=, --exec-delay= Delay the execution of RUN instructions by the given number of seconds. This option might be useful when debugging system crashes during coldplug caused by loading non-working kernel modules. -t=, --event-timeout= Set the number of seconds to wait for events to finish. After this time, the event will be terminated. The default is 180 seconds. -s, --timeout-signal= Set the signal which systemd-udevd will send to forked off processes after reaching event timeout. The setting can be overriden at boot time with the kernel command line option udev.timeout_signal=. Setting to SIGABRT may be helpful in order to debug worker timeouts. Defaults to SIGKILL. Note that setting the option on the command line overrides the setting from the configuration file. -N=, --resolve-names= Specify when systemd-udevd should resolve names of users and groups. When set to early (the default), names will be resolved when the rules are parsed. When set to late, names will be resolved for every event. When set to never, names will never be resolved and all devices will be owned by root. -h, --help Print a short help text and exit. --version Print a short version string and exit.
Parameters starting with "rd." will be read when systemd-udevd is used in an initrd. udev.log_priority=, rd.udev.log_priority= Set the log level. udev.children_max=, rd.udev.children_max= Limit the number of events executed in parallel. udev.exec_delay=, rd.udev.exec_delay= Delay the execution of RUN instructions by the given number of seconds. This option might be useful when debugging system crashes during coldplug caused by loading non-working kernel modules. udev.event_timeout=, rd.udev.event_timeout= Wait for events to finish up to the given number of seconds. This option might be useful if events are terminated due to kernel drivers taking too long to initialize. udev.timeout_signal=, rd.udev.timeout_signal= Specifies a signal that systemd-udevd will send to workers on timeout. Note that kernel command line option overrides both the setting in the configuration file and the one on the program command line. net.ifnames= Network interfaces are renamed to give them predictable names when possible. It is enabled by default; specifying 0 disables it. net.naming-scheme= Network interfaces are renamed to give them predictable names when possible (unless net.ifnames=0 is specified, see above). With this kernel command line option it is possible to pick a specific version of this algorithm and override the default chosen at compilation time. Expects one of the naming scheme identifiers listed in systemd.net-naming-scheme(7), or "latest" to select the latest scheme known (to this particular version of systemd-udevd.service). Note that selecting a specific scheme is not sufficient to fully stabilize interface naming: the naming is generally derived from driver attributes exposed by the kernel. As the kernel is updated, previously missing attributes systemd-udevd.service is checking might appear, which affects older name derivation algorithms, too.
udev.conf(5), udev(7), udevadm(8)
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 2020-06-09. (At that time, the date of the most recent commit that was found in the repos‐ itory was 2020-06-09.) 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 email@example.com systemd 245 SYSTEMD-UDEVD.SERVICE(8)
Pages that refer to this page: udev.conf(5), 30-systemd-environment-d-generator(7), file-hierarchy(7), systemd.index(7), systemd-vconsole-setup(8), systemd-vconsole-setup.service(8)