:: Re: [Dng] printing (was Re: Readine…
Kezdőlap
Delete this message
Reply to this message
Szerző: Steve Litt
Dátum:  
Címzett: dng
Tárgy: Re: [Dng] printing (was Re: Readiness notification)
On Sun, 14 Jun 2015 17:22:11 +0200
Laurent Bercot <ska-devel@???> wrote:


>
> [ Stephanie ]
> > I'm firmly in the camp that process supervision is evil, because
> > service failures on a *nix system should not happen
>
> They should not happen. But they do.
> And auto-restart is not the only thing that process supervision
> gives you. Ease of process management is a big one for me.


This is an exact analogy of saying "I believe seatbelts are evil,
because car crashes should not happen."

Shouldn't, but do. Besides that, some drivers are incompetant. Just
like some daemon authors are incompetant. Saying incompetent daemons
shouldn't exist on Linux is exactly the same as saying incompetent
drivers shouldn't exist on the highway. They shouldn't, but they always
will.

>
>
> > and when they do
> > they should be a really big inconvenient deal that wakes people up
> > at 3am - because that's the sort of thing that gets problems
> > noticed and fixed.
>
> Nothing prevents you from having an alert that wakes the admin up
> when the service fails. But while the admin is waking up and logging
> in, it's better if the service has been restarted and is trying to
> be operational.


And, if it's preferable that the service *not* start (let's say it's a
HIPPA violation or something), then you can set any process supervisor
to run the thing once. Most of them have that ability built in, a few
must be kludged (LittKit's lk_forever), but they can all do it.


SteveT

Steve Litt
June 2015 featured book: The Key to Everyday Excellence
http://www.troubleshooters.com/key