System and Service Manager
https://www.freedesktop.org/wiki/Software/systemd
systemd is a system and service manager that runs as PID 1 and starts
the rest of the system. It provides aggressive parallelization
capabilities, uses socket and D-Bus activation for starting services,
offers on-demand starting of daemons, keeps track of processes using
Linux control groups, maintains mount and automount points, and
implements an elaborate transactional dependency-based service control
logic. systemd supports SysV and LSB init scripts and works as a
replacement for sysvinit. Other parts of this package are a logging daemon,
utilities to control basic system configuration like the hostname,
date, locale, maintain a list of logged-in users, system accounts,
runtime directories and settings, and daemons to manage simple network
configuration, network time synchronization, log forwarding, and name
resolution.
Version: 248
See also: systemd-bootchart, systemd-container, systemd-devel, systemd-journal-remote, systemd-networkd, systemd-pam, systemd-swap, systemd-udev.
General Commands | |
| busctl | Introspect the bus |
| coredumpctl | Retrieve and process saved core dumps and metadata |
| homectl | Create, remove, change or inspect home directories |
| hostnamectl | Control the system hostname |
| init | alias for systemd |
| journalctl | Query the systemd journal |
| localectl | Control the system locale and keyboard layout settings |
| loginctl | Control the systemd login manager |
| oomctl | Analyze the state stored in systemd-oomd |
| portablectl | Attach, detach or inspect portable service images |
| resolvconf | alias for resolvectl |
| resolvectl | Resolve domain names, IPV4 and IPv6 addresses, DNS resource records, and services; introspect and reconfigure the DNS resolver |
| systemctl | Control the systemd system and service manager |
| systemd | systemd system and service manager |
| systemd-analyze | Analyze and debug system manager |
| systemd-ask-password | Query the user for a system password |
| systemd-cat | Connect a pipeline or program's output with the journal |
| systemd-cgls | Recursively show control group contents |
| systemd-cgtop | Show top control groups by their resource usage |
| systemd-cryptenroll | Enroll PKCS#11, FIDO2, TPM2 token/devices to LUKS2 encrypted volumes |
| systemd-delta | Find overridden configuration files |
| systemd-detect-virt | Detect execution in a virtualized environment |
| systemd-dissect | Dissect file system OS images |
| systemd-escape | Escape strings for usage in systemd unit names |
| systemd-firstboot | Initialize basic system settings on or before the first boot-up of a system |
| systemd-firstboot.service | alias for systemd-firstboot |
| systemd-id128 | Generate and print sd-128 identifiers |
| systemd-inhibit | Execute a program with an inhibition lock taken |
| systemd-machine-id-setup | Initialize the machine ID in /etc/machine-id |
| systemd-mount | Establish and destroy transient mount or auto-mount points |
| systemd-notify | Notify service manager about start-up completion and other daemon status changes |
| systemd-path | List and query system and user paths |
| systemd-run | Run programs in transient scope units, service units, or path-, socket-, or timer-triggered service units |
| systemd-socket-activate | Test socket activation of daemons |
| systemd-tty-ask-password-agent | List or process pending systemd password requests |
| systemd-umount | alias for systemd-mount |
| timedatectl | Control the system time and date |
| userdbctl | Inspect users, groups and group memberships |
File Formats | |
| binfmt.d | Configure additional binary formats for executables at boot |
| coredump.conf | Core dump storage configuration files |
| coredump.conf.d | alias for coredump.conf |
| crypttab | Configuration for encrypted block devices |
| dnssec-trust-anchors.d | DNSSEC trust anchor configuration files |
| environment.d | Definition of user service environment |
| homed.conf | Home area/user account manager configuration files |
| homed.conf.d | alias for homed.conf |
| hostname | Local hostname configuration file |
| journald.conf | Journal service configuration files |
| journald.conf.d | alias for journald.conf |
| journald@.conf | alias for journald.conf |
| locale.conf | Configuration file for locale settings |
| localtime | Local timezone configuration file |
| logind.conf | Login manager configuration files |
| logind.conf.d | alias for logind.conf |
| machine-id | Local machine ID configuration file |
| machine-info | Local machine information file |
| oomd.conf | Global systemd-oomd configuration files |
| oomd.conf.d | alias for oomd.conf |
| org.freedesktop.LogControl1 | D-Bus interface to query and set logging configuration |
| org.freedesktop.home1 | The D-Bus interface of systemd-homed |
| org.freedesktop.hostname1 | The D-Bus interface of systemd-hostnamed |
| org.freedesktop.locale1 | The D-Bus interface of systemd-localed |
| org.freedesktop.login1 | The D-Bus interface of systemd-logind |
| org.freedesktop.oom1 | The D-Bus interface of systemd-oomd |
| org.freedesktop.portable1 | The D-Bus interface of systemd-portabled |
| org.freedesktop.resolve1 | The D-Bus interface of systemd-resolved |
| org.freedesktop.systemd1 | The D-Bus interface of systemd |
| org.freedesktop.timedate1 | The D-Bus interface of systemd-timedated |
| os-release | Operating system identification |
| resolved.conf | Network Name Resolution configuration files |
| resolved.conf.d | alias for resolved.conf |
| sysctl.d | Configure kernel parameters at boot |
| system.conf.d | alias for systemd-system.conf |
| systemd-system.conf | System and session service manager configuration files |
| systemd-user-runtime-dir | alias for user@.service |
| systemd-user.conf | alias for systemd-system.conf |
| systemd.automount | Automount unit configuration |
| systemd.device | Device unit configuration |
| systemd.dnssd | DNS-SD configuration |
| systemd.exec | Execution environment configuration |
| systemd.kill | Process killing procedure configuration |
| systemd.link | Network device configuration |
| systemd.mount | Mount unit configuration |
| systemd.negative | alias for dnssec-trust-anchors.d |
| systemd.netdev | Virtual Network Device configuration |
| systemd.network | Network configuration |
| systemd.nspawn | Container settings |
| systemd.path | Path unit configuration |
| systemd.positive | alias for dnssec-trust-anchors.d |
| systemd.preset | Service enablement presets |
| systemd.resource-control | Resource control unit settings |
| systemd.scope | Scope unit configuration |
| systemd.service | Service unit configuration |
| systemd.slice | Slice unit configuration |
| systemd.socket | Socket unit configuration |
| systemd.swap | Swap unit configuration |
| systemd.target | Target unit configuration |
| systemd.timer | Timer unit configuration |
| systemd.unit | Unit configuration |
| sysusers.d | Declarative allocation of system users and groups |
| tmpfiles.d | Configuration for creation, deletion and cleaning of volatile and temporary files |
| user-runtime-dir@.service | alias for user@.service |
| user.conf.d | alias for systemd-system.conf |
| user@.service | System units to start the user manager |
| veritytab | Configuration for verity block devices |
Miscellanea | |
| bootup | System bootup process |
| daemon | Writing and packaging system daemons |
| file-hierarchy | File system hierarchy overview |
| kernel-command-line | Kernel command line parameters |
| systemd.directives | Index of configuration directives |
| systemd.environment-generator | systemd environment file generators |
| systemd.generator | systemd unit generators |
| systemd.index | List all manpages from the systemd project |
| systemd.journal-fields | Special journal fields |
| systemd.net-naming-scheme | Network device naming schemes |
| systemd.offline-updates | Implementation of offline updates in systemd |
| systemd.special | Special systemd units |
| systemd.syntax | General syntax of systemd configuration files |
| systemd.time | Time and date specifications |
System Administration | |
| 30-systemd-environment-d-generator | alias for systemd-environment-d-generator |
| halt | Halt, power-off or reboot the machine |
| nss-myhostname | Hostname resolution for the locally configured system hostname |
| nss-resolve | Hostname resolution via systemd-resolved.service |
| nss-systemd | UNIX user and group name resolution for user/group lookup via Varlink |
| poweroff | alias for halt |
| rc-local.service | alias for systemd-rc-local-generator |
| reboot | alias for halt |
| runlevel | Print previous and current SysV runlevel |
| shutdown | Halt, power-off or reboot the machine |
| systemd-ask-password-console.path | alias for systemd-ask-password-console.service |
| systemd-ask-password-console.service | Query the user for system passwords on the console and via wall |
| systemd-ask-password-wall.path | alias for systemd-ask-password-console.service |
| systemd-ask-password-wall.service | alias for systemd-ask-password-console.service |
| systemd-binfmt | alias for systemd-binfmt.service |
| systemd-binfmt.service | Configure additional binary formats for executables at boot |
| systemd-boot-check-no-failures | alias for systemd-boot-check-no-failures.service |
| systemd-boot-check-no-failures.service | verify that the system booted up cleanly |
| systemd-coredump | Acquire, save and process core dumps |
| systemd-coredump.socket | alias for systemd-coredump |
| systemd-coredump@.service | alias for systemd-coredump |
| systemd-debug-generator | Generator for enabling a runtime debug shell and masking specific units at boot |
| systemd-environment-d-generator | Load variables specified by environment.d |
| systemd-fstab-generator | Unit generator for /etc/fstab |
| systemd-getty-generator | Generator for enabling getty instances on the console |
| systemd-halt.service | System shutdown logic |
| systemd-homed | alias for systemd-homed.service |
| systemd-homed.service | Home Area/User Account Manager |
| systemd-hostnamed | alias for systemd-hostnamed.service |
| systemd-hostnamed.service | Daemon to control system hostname from programs |
| systemd-initctl | alias for systemd-initctl.service |
| systemd-initctl.service | /dev/initctl compatibility |
| systemd-initctl.socket | alias for systemd-initctl.service |
| systemd-journald | alias for systemd-journald.service |
| systemd-journald-audit.socket | alias for systemd-journald.service |
| systemd-journald-dev-log.socket | alias for systemd-journald.service |
| systemd-journald-varlink@.socket | alias for systemd-journald.service |
| systemd-journald.service | Journal service |
| systemd-journald.socket | alias for systemd-journald.service |
| systemd-journald@.service | alias for systemd-journald.service |
| systemd-journald@.socket | alias for systemd-journald.service |
| systemd-kexec.service | alias for systemd-halt.service |
| systemd-localed | alias for systemd-localed.service |
| systemd-localed.service | Locale bus mechanism |
| systemd-logind | alias for systemd-logind.service |
| systemd-logind.service | Login manager |
| systemd-machine-id-commit.service | Commit a transient machine ID to disk |
| systemd-network-generator | alias for systemd-network-generator.service |
| systemd-network-generator.service | Generate network configuration from the kernel command line |
| systemd-oomd | alias for systemd-oomd.service |
| systemd-oomd.service | A userspace out-of-memory (OOM) killer |
| systemd-portabled | alias for systemd-portabled.service |
| systemd-portabled.service | Portable service manager |
| systemd-poweroff.service | alias for systemd-halt.service |
| systemd-rc-local-generator | Compatibility generator and service to start /etc/rc.d/rc.local during boot |
| systemd-reboot.service | alias for systemd-halt.service |
| systemd-resolved | alias for systemd-resolved.service |
| systemd-resolved.service | Network Name Resolution manager |
| systemd-run-generator | Generator for invoking commands specified on the kernel command line as system service |
| systemd-shutdown | alias for systemd-halt.service |
| systemd-socket-proxyd | Bidirectionally proxy local sockets to another (possibly remote) socket |
| systemd-sysctl | alias for systemd-sysctl.service |
| systemd-sysctl.service | Configure kernel parameters at boot |
| systemd-sysext | Activates System Extension Images |
| systemd-sysext.service | alias for systemd-sysext |
| systemd-system-update-generator | Generator for redirecting boot to offline update mode |
| systemd-sysusers | Allocate system users and groups |
| systemd-sysusers.service | alias for systemd-sysusers |
| systemd-sysv-generator | Unit generator for SysV init scripts |
| systemd-time-wait-sync | alias for systemd-time-wait-sync.service |
| systemd-time-wait-sync.service | Wait until kernel time is synchronized |
| systemd-timedated | alias for systemd-timedated.service |
| systemd-timedated.service | Time and date bus mechanism |
| systemd-tmpfiles | Creates, deletes and cleans up volatile and temporary files and directories |
| systemd-tmpfiles-clean.service | alias for systemd-tmpfiles |
| systemd-tmpfiles-clean.timer | alias for systemd-tmpfiles |
| systemd-tmpfiles-setup.service | alias for systemd-tmpfiles |
| systemd-update-done | alias for systemd-update-done.service |
| systemd-update-done.service | Mark /etc/ and /var/ fully updated |
| systemd-update-utmp | alias for systemd-update-utmp.service |
| systemd-update-utmp-runlevel.service | alias for systemd-update-utmp.service |
| systemd-update-utmp.service | Write audit and utmp updates at bootup, runlevel changes and shutdown |
| systemd-user-sessions | alias for systemd-user-sessions.service |
| systemd-user-sessions.service | Permit user logins after boot, prohibit user logins at shutdown |
| systemd-userdbd | alias for systemd-userdbd.service |
| systemd-userdbd.service | JSON User/Group Record Query Multiplexer/NSS Compatibility |
| systemd-veritysetup | alias for systemd-veritysetup@.service |
| systemd-veritysetup-generator | Unit generator for integrity protected block devices |
| systemd-veritysetup@.service | Disk integrity protection logic |
| systemd-xdg-autostart-generator | User unit generator for XDG autostart files |
| telinit | Change SysV runlevel |