diff options
Diffstat (limited to 'nixos/doc/manual/administration/service-mgmt.xml')
| -rw-r--r-- | nixos/doc/manual/administration/service-mgmt.xml | 26 |
1 files changed, 5 insertions, 21 deletions
diff --git a/nixos/doc/manual/administration/service-mgmt.xml b/nixos/doc/manual/administration/service-mgmt.xml index 1b9c745eb59f..4ad30ce55a86 100644 --- a/nixos/doc/manual/administration/service-mgmt.xml +++ b/nixos/doc/manual/administration/service-mgmt.xml @@ -5,21 +5,10 @@ xml:id="sec-systemctl"> <title>Service Management</title> <para> - In NixOS, all system services are started and monitored using the systemd - program. Systemd is the “init” process of the system (i.e. PID 1), the - parent of all other processes. It manages a set of so-called “units”, - which can be things like system services (programs), but also mount points, - swap files, devices, targets (groups of units) and more. Units can have - complex dependencies; for instance, one unit can require that another unit - must be successfully started before the first unit can be started. When the - system boots, it starts a unit named <literal>default.target</literal>; the - dependencies of this unit cause all system services to be started, file - systems to be mounted, swap files to be activated, and so on. + In NixOS, all system services are started and monitored using the systemd program. Systemd is the “init” process of the system (i.e. PID 1), the parent of all other processes. It manages a set of so-called “units”, which can be things like system services (programs), but also mount points, swap files, devices, targets (groups of units) and more. Units can have complex dependencies; for instance, one unit can require that another unit must be successfully started before the first unit can be started. When the system boots, it starts a unit named <literal>default.target</literal>; the dependencies of this unit cause all system services to be started, file systems to be mounted, swap files to be activated, and so on. </para> <para> - The command <command>systemctl</command> is the main way to interact with - <command>systemd</command>. Without any arguments, it shows the status of - active units: + The command <command>systemctl</command> is the main way to interact with <command>systemd</command>. Without any arguments, it shows the status of active units: <screen> <prompt>$ </prompt>systemctl -.mount loaded active mounted / @@ -30,8 +19,7 @@ graphical.target loaded active active Graphical Interface </screen> </para> <para> - You can ask for detailed status information about a unit, for instance, the - PostgreSQL database service: + You can ask for detailed status information about a unit, for instance, the PostgreSQL database service: <screen> <prompt>$ </prompt>systemctl status postgresql.service postgresql.service - PostgreSQL Server @@ -51,9 +39,7 @@ Jan 07 15:55:57 hagbard postgres[2390]: [1-1] LOG: database system is ready to Jan 07 15:55:57 hagbard postgres[2420]: [1-1] LOG: autovacuum launcher started Jan 07 15:55:57 hagbard systemd[1]: Started PostgreSQL Server. </screen> - Note that this shows the status of the unit (active and running), all the - processes belonging to the service, as well as the most recent log messages - from the service. + Note that this shows the status of the unit (active and running), all the processes belonging to the service, as well as the most recent log messages from the service. </para> <para> Units can be stopped, started or restarted: @@ -62,9 +48,7 @@ Jan 07 15:55:57 hagbard systemd[1]: Started PostgreSQL Server. # systemctl start postgresql.service # systemctl restart postgresql.service </screen> - These operations are synchronous: they wait until the service has finished - starting or stopping (or has failed). Starting a unit will cause the - dependencies of that unit to be started as well (if necessary). + These operations are synchronous: they wait until the service has finished starting or stopping (or has failed). Starting a unit will cause the dependencies of that unit to be started as well (if necessary). </para> <!-- - cgroups: each service and user session is a cgroup |