Re: [gentoo-amd64] Re: Systemd migration: opinion and questions

[Marc Joliet]

Am Mon, 2 Mar 2015 05:13:26 +0000 (UTC)
schrieb Duncan <1i5t5.duncan@×××.net>:

> Rich Freeman posted on Sun, 01 Mar 2015 14:13:53 -0500 as excerpted:
>
> > On Sun, Mar 1, 2015 at 1:20 PM, Marc Joliet <marcec@×××.de> wrote:
> >>
> >> Regardless: thoughts?
> >
> > I'd probably just do this:
> >> Am Sun, 1 Mar 2015 08:34:19 -0500 schrieb Rich Freeman
> >> <rich0@g.o>:
> >>>
> >>> The timer keeps running if you set the dependency on the service.  So,
> >>> next time the timer runs, it will try again.  You might want to just
> >>> set an hourly job and have it check for a successful run in the last
> >>> day or whatever.
> >>>
> > You could of course trigger this from either the mount or hourly.
> > Anytime you mount the drive or every hour systemd will run the service,
> > and the service will see if it managed to do a backup/etc in the last
> > day/week/whatever, and then run if appropriate.
>
> This is actually how I setup several former cron-jobs as systemd timers,
> here, based on an hourly check somewhat similar to what most crons
> (including gentoo's for over 10 years now and mandrake's before that) are
> actually setup to do to get around the fact that cron won't on-its-own
> trigger after restart if the machine was down or cron not running when
> the configured time for a job ran.
>
> Here's how I have it setup here.  Note that my initials are jed, and I
> use them regularly as a prefix/suffix to denote custom configs (here,
> systemd units) I've created myself, as opposed to those shipped in
> whatever package.
>
[GIGASNIP thorough explanation ;) ]

I pretty much thought that's what Rich was alluding to, but thanks for showing
that it's not *that* much extra complication (and how one can use a target unit
for this). I never really looked at how these things are done by run-crons (and
similar).

Just for completeness: I use fcron instead of vixie-cron, so some of the stuff
systemd timers can do was already known to me.   For example, in fcron, lines
can start with "@" to denote that they run relative to system startup (e.g, "@
5" for "every five minutes after boot).  The "first" option specifies how long
to wait before starting an entry for the first time, analogous to "OnBootSec".

Anyway, like I mentioned before, I'll revisit this once I've solved the HDD
problem (or not, if it turns out to be a firmware issue).

Greetings
-- 
Marc Joliet
--
"People who think they know everything really annoy those of us who know we
don't" - Bjarne Stroustrup