конфигурация таймера (Timer unit configuration)
Автоматические зависимости (Automatic dependencies)
Implicit Dependencies
The following dependencies are implicitly added:
• Timer units automatically gain a Before= dependency on the
service they are supposed to activate.
Default Dependencies
The following dependencies are added unless
DefaultDependencies=no is set:
• Timer units will automatically have dependencies of type
Requires= and After= on sysinit.target, a dependency of type
Before= on timers.target, as well as Conflicts= and Before=
on shutdown.target to ensure that they are stopped cleanly
prior to system shutdown. Only timer units involved with
early boot or late system shutdown should disable the
DefaultDependencies= option.
• Timer units with at least one OnCalendar= directive acquire a
pair of additional After= dependencies on time-set.target and
time-sync.target, in order to avoid being started before the
system clock has been correctly set. See systemd.special(7)
for details on these two targets.