On Thu, Sep 24, 2015 at 07:20:25PM +0200, Laurent Bercot wrote:
> On 24/09/2015 17:51, Rainer Weikusat wrote:
> >If it starts working within less than five minutes, users will forget
> >about it faster than they could complain, especially for a system which
> >is usually supposed to be running. But that's actually a digression.
>
> Five minutes? And you think it's acceptable? Sorry, I don't have five
> minutes to waste every time a program fails. Also, this is 2015: if a
> program isn't responsive within 30 seconds, users will come knocking at
> your door raging - and they will be right.

But let's be honest here: how many times does it happen that you have
to reboot a production server nowadays? It is quite rare that a
failing program actually needs a reboot, right? And even when it
happens, 1 minute or 5 minutes boot won't change your overall uptime
percentage that much. If you are at 99.999% with a 1 minute boot
(which corresponds to one reboot every 2 months and a half, already
ways too much for the vast majority of production servers) with an
exagerated 5 minutes boot you will move to 99.995%.

If your application is so critical to require 99.999%, then you should
already have a fail-over strategy there, so you really don't mind how
much time the failing server needs to come up again, since another one
has alreasy taken its role and it will remain idle until the next
failure happens.

Again, at the end of the day all this worry about boot speed matters
only for mobile devices. Which probably are a common use case, but
have nothing to do with high availability.

My2Cents

KatolaZ

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[ Enzo Nicosia aka KatolaZ --- GLUG Catania -- Freaknet Medialab ]
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