On Wed, Dec 06, 2017 at 12:12:45PM -0300, Renaud (Ron) OLGIATI wrote:
> On Wed, 6 Dec 2017 15:25:06 +0100
> Alessandro Selli <alessandroselli@???> wrote:
>
> > > I notice that since I upgraded from Bebian Wheezy to Devuan Jessie my box
> > > runs periodic jobs through anacron instead of cron.
> > > This sometimes causes heavy jobs to run at inconvenient times.
> > > Given my box runs 24/7, is there a simple way to banish Anacron, and run
> > > Cron at fixed times, in the wee hours of the night for instance ?
>
> > You can run as root: update-rc.d anacron disable
> > Or you can disable the unwanted anacron jobs in /etc/anacrontab.
>
> I dont want to remove the jobs presently done by Anacron, but have them done by Cron at a suitable time.
>
> Will that happen if I disable Anacron ?
>

anacron(8) reads its jobs from /etc/anacrontab (see
anacrontab(5)). Those jobs are specified with a syntax similar to that
of cron, with two main differences:

- each job has only a period in days and a delay (in minutes);

  - anacron is normally run only once (at startup) and then exits when
    it's done, or has to be called explicitly.

In the default ascii configuration, anacron only tries to run the
daily, weekly, and monthly cron(8) jobs, if they have not been run in
the last X days. However, those jobs are normally included in the
default crontab(5) in ascii.

Long story short: you can disable anacron if your machine is up
24/7. otherwise, you should launch anacron every now and then, maybe
as a cron task (this is indeed how cron.daily, cron.weekly, and
cron.monthly are run if anacron is around...).

HTH

KatolaZ

-- 
[ ~.,_  Enzo Nicosia aka KatolaZ - Devuan -- Freaknet Medialab  ]  
[     "+.  katolaz [at] freaknet.org --- katolaz [at] yahoo.it  ]
[       @)   http://kalos.mine.nu ---  Devuan GNU + Linux User  ]
[     @@)  http://maths.qmul.ac.uk/~vnicosia --  GPG: 0B5F062F  ] 
[ (@@@)  Twitter: @KatolaZ - skype: katolaz -- github: KatolaZ  ]