[Pacemaker] dopd on openais

Lars Marowsky-Bree lmb at suse.de
Tue Jun 9 16:11:21 UTC 2009


On 2009-06-09T13:24:57, Lars Ellenberg <lars.ellenberg at linbit.com> wrote:

> generic question about master score and globally-unique=false.
> I don't think it can even work.

Why not? They do.

> but if they can work, how, and why,
> are master scores supposed to work?
> 
> if _by definition_ the instances are not distinguishable,
> why would placing a master preference on drbd-xy:1 prevent
> drbd-xy:1 from being allocated on the "wrong" node
> accessing the "wrong" data?
> 
> if we are "globally-unique=false" (and I really think drbd would fall
> into that category), then there is no difference whether I place
> the better score on drbd-xy:0 or drbd-xy:1.
> appart from _accidentally_ colocating drbd-xy:0 with the same (group of)
> hosts, "most of the time".
> 
> what am I missing?

I'm not sure I follow. Placing a master preference for an anonymous
instance effectively applies to the whole clone on that node.

If you set a negative/zero master preference on a node, drbd won't run
there.

If you set a positive one, the highest scoring node will be preferred.

Maybe I'm missing the real question?

Regards,
    Lars

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