[Linux-HA] Re: [Pacemaker] Ordered attribute of clone resources

[Andreas Mock]

> -----Ursprüngliche Nachricht-----
> Von: linux-ha-bounces at lists.linux-ha.org 
> [mailto:linux-ha-bounces at lists.linux-ha.org] Im Auftrag von 
> Lars Marowsky-Bree
> Gesendet: Samstag, 26. Januar 2008 21:41
> An: The Pacemaker cluster resource manager; 'General Linux-HA 
> mailing list'
> Betreff: [Linux-HA] Re: [Pacemaker] Ordered attribute of 
> clone resources

> No, monitors are independent from each other. They also don't receive
> the notify attributes (nor are pre/post notifies sent for them) - that
> would be too much effort to synchronize and replicate.
> 

Hi Lars,

this can have an impact on monitoring stonith resource agents if you
want to use clones. There are many stonith devices which do allow only
extactly one connection at a time. The monitor action is often implemented
to connect to the stonith device to see if it's alive.
Now if you use clones, and the stonith RA is run on more then one node
it could happen that the monitor action is triggered at the same time
resulting in one monitor action to fail because two instances try to connect
to the same stonith device.

Am I wrong with that conclusion?

Best regards
Andreas Mock