Re: Default services enabled

[Reindl Harald]

Am 24.08.2011 20:40, schrieb Adam Williamson:
>  On Wed, 2011-08-24 at 19:59 +0200, Lennart Poettering wrote:
> > On Wed, 24.08.11 10:05, Adam Williamson (awilliam(a)redhat.com) wrote:
> >
> >>> FWIW, I do think that there may be use-cases for socket activation of a
> >>> database.  I'd like to support the option ... the problem is to do so
> >>> without breaking existing, expected behaviors.
> >>
> >> It was noted up-thread that systemd can tell you whether the underlying
> >> daemon is running or not, though I guess that doesn't tell you whether
> >> it's entirely in a functional state. You could do a two-stage thing:
> >> check with systemd whether the daemon is running, and ping it if so?
> >
> > systemd will put services only in "running" state if they are fully up
> > and told systemd so. They'll be in "starting" until that time. All we
> > need for this is that services either use Type=forking and double
> > fork+exit in parent, or use Type=notify and sd_notify("READY=1") as soon
> > as they are fully up.
>  
>  Sure, but it would be possibly for mysql to be 'fully up' under
>  systemd's definition (i.e. the mysqld process has successfully executed
>  and is running happily) while not actually being properly configured to
>  serve external requests, right? Bad mysql config, firewall in the way,
>  whatever...point is that systemd can't really know for sure that the
>  underlying process is 100% working, only that it's _running_ 
and that is why you need only socket-activation for the unix-socket
to provide relieable system-boot with activation and you nagios will
check over TCP and so has NOTHING really NOTHING to do with systemd