[Initscripts-ng-devel] Defining the workgroup objectives

[paddy]

On Tue, Jul 26, 2005 at 02:03:56PM +0200, Sven Mueller wrote:
> paddy wrote on 26/07/2005 12:36:
> 
> >> On Mon, Jul 25, 2005 at 04:12:44PM -0300, Otavio Salvador wrote:
> >
> >>>>This problem isn't at scope IMHO. The current implementation of init
> >>>>system also don't  handle cross-machine issues.
> >
> >>
> >> heartbeat ?
> 
> 
> Huh? Where does heartbeat handle cross-machine dependencies?

heartbeat contains an init system, arguably is part of the init system
in some configurations, and handles cross-machine issues.

I'm not aware of special mechanisms in heartbeat1 for making a service
depend on a service on another machine, as the original poster asked,
but another post here describes how that can be trivially done.  
I don't know whether such is slated for heartbeat2.

Nevertheless, whether heartbeat or sysvinit, it would seem that
at least some cross-machine dependencies _can_ be handled, and 
without even any special support.

I hope heartbeat will be considered in the initscripts-ng-devel
discussion.  This seemed like a plausible excuse to bring it up.

For example, I understand heartbeat uses init scripts which are lsb
compliant - its expects strict interfaces, behaviour and output.
The current debian init-scripts cannot be used directly,
but need wrapping (not that I find this especially onerous).

As another example, consider a dependency driven init system.
Should it only address services in its own namespace ? 
And have heartbeat is a seperate namespace ?

Cross-machine dependencies seem like a natural enough aspect of 
some clusters, and more and more clustering software is being 
developed and going into Debian.

It may be that whole problem is simply too big to consider in the 
context initscripts-ng-devel, but I would be wary of simply 
ignoring it.  By considering the wider picture, we might learn
something, or avoid mistakes. 

Regards,
Paddy
-- 
Perl 6 will give you the big knob. -- Larry Wall