schnippets/systemd/timer.timer

[Unit]
Description=Run A Service on a Timer

[Timer]
#OnActiveSec=
OnBootSec=5m
#OnStartupSec=
OnUnitActiveSec=1h
#OnUnitInactiveSec=

# OnCalendar Valid Time Specs
# https://www.freedesktop.org/software/systemd/man/systemd.time.html#
#OnCalendar=

# Delay the timer by a randomly selected, evenly distributed
# amount of time between 0 and the specified time value.
#RandomizedDelaySec=

Unit=service_to_start.service

# If true, the time when the service unit was last triggered
# is stored on disk. When the timer is activated, the service
# unit is triggered immediately if it would have been
# triggered at least once during the time when the timer was
# inactive. This is useful to catch up on missed runs of the
# service when the machine was off. Note that this setting only
# has an effect on timers configured with OnCalendar=.
#Persistent=false

# If true, an elapsing timer will cause the system to resume
# from suspend, should it be suspended and if the system
# supports this. Note that this option will only make sure the
# system resumes on the appropriate times, it will not take
# care of suspending it again after any work that is to be
# done is finished.
#WakeSystem=false

[Install]
WantedBy=timers.target