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anacrontab(5)


NAME

   /etc/anacrontab - monotonic jobs

DESCRIPTION

   The file /etc/anacrontab follow the rules previously set by anacron(8).

   Lines starting with '#' are comments.

   Environment variables can be set using VAR=VALUE keypairs.

   The   special   RANDOM_DELAY   (in  minutes)  environment  variable  is
   translated to AccuracySec=.

   The  special  START_HOURS_RANGE  (in  hours)  environment  variable  is
   translated  to  the  hour component of OnCalendar=.  anacron expect a
   range in the  format  ##-##,  systemd-crontab-generator  only  use  the
   starting hour of the range as reference.

   The other lines are job-descriptions that follow this layout:

   period delay job-identifier command

   *      period  is  a number of days to wait between each job execution,
          or special values @daily, @weekly, @monthly, @yearly

   *      delay is a number of extra minutes to wait before starting  job.
          It is translated in OnBootSec=

   *      job-identifier  is a single word. systemd-crontab-generator uses
          it   to   construct   the   dynamic   unit   names:   cron-<job-
          identifier>-root-0.timer       and      matching      cron-<job-
          identifier>-root-0.service

   *      command is the command that is run by a shell

BUGS

   systemd-crontab-generator doesn't support multiline commands.

   Any period greater than 30 is rounded to the closest month

   There  are  subtle  differences  on  how  anacron  &   systemd   handle
   persistente  timers: anacron will run a weekly job at most once a week,
   with allways a minimum delay of 6 days between runs; where systemd will
   try to run it every monday at 00:00; or as soon the system boot. In the
   most extreme case, if a system was only started on sunday; a weekly job
   will run this day and the again the next (mon)day.
   With  careful  manual  settings,  it  would be possible to run the real
   anacron binary (not your distro's package) with  systemd-cron;  if  you
   need an identical behaviour.
   There is no difference for the daily job.

DIAGNOSTICS

   After  editing /etc/anacrontab, you can run journalctl -n and systemctl
   list-timers to see if the timers have well been updated.

SEE ALSO

   systemd-crontab-generator(8), systemd.timer(5)

AUTHOR

   Alexandre Detiste <alexandre.detiste@gmail.com>



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