- <filename>shutdown.target</filename>. These ensure
- that timer units are stopped cleanly prior to system
- shutdown. Only timer units involved with early boot or
- late system shutdown should disable this
- option.</para>
+ <filename>shutdown.target</filename> to ensure that
+ they are stopped cleanly prior to system shutdown.
+ Timer units with at least one
+ <varname>OnCalendar=</varname> directive will have an
+ additional <varname>After=</varname> dependency on
+ <filename>timer-sync.target</filename> to avoid
+ being started before the system clock has been
+ correctly set. Only timer units involved with early
+ boot or late system shutdown should disable the
+ <varname>DefaultDependencies=</varname> option.</para>