[Pacemaker] Enable remote monitoring

[Lars Marowsky-Bree]

On 2012-11-09T14:06:29, Dejan Muhamedagic <dejanmm at fastmail.fm> wrote:

> > > > Uh? How should this be handled by the RA? Can you elaborate?
> > > For instance, using expect to wait for the login prompt on the
> > > console. Or, if that's possible, employing libvirt to get the
> > > current runlevel. We already discussed this. Your objection was
> > > that this won't work with the other OS.
> > Oh. This. No, this is inacceptable.
> I'm really curious to know why exactly.

Exactly because of this - the need to parse console output, which is
very OS specific, and prone to break, and not all services that we
monitor may show up on the console at all. Getting more reliable metrics
would require instrumenting the guest (such as understanding the
runlevel it is at), and that is also a No-No. The idea is to be able to
run unmodified guests.

> > And also doesn't really help with getting the state/readiness of
> > services the guest might provide.
> Isn't it that one gets a login prompt only once the host reached a
> certain run level?

Services may start in the background. The console may either be text,
graphical, or network only.


Regards,
    Lars

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