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SubjectRe: Linux Cluster using shared scsi

> > > ...
> > >
> > > If told to hold a reservation, then resend your reservation request once every
> > > 2 seconds (this actually has very minimal CPU/BUS usage and isn't as big a
> > > deal as requesting a reservation every 2 seconds might sound). The first time
> > > the reservation is refused, consider the reservation stolen by another machine
> > > and exit (or optionally, reboot).
> >
> > Umm. Reboot? What do you think this is? Windoze?
> It's the *only* way to guarantee that the drive is never touched by more than
> one machine at a time (notice, I've not been talking about a shared use drive,
> only one machine in the cluster "owns" the drive at a time, and it isn't for
> single transactions that it owns the drive, it owns the drive for as long as
> it is alive, this is a limitation of the filesystes currently available in
> mainstream kernels). The reservation conflict and subsequent reboot also
> *only* happens when a reservation has been forcefully stolen from a

I do not believe reboot from kernel is right approach. Tell init with
special signal, maybe; but do not reboot forcefully. This is policy;
doing reboot might be right answer in 90% cases; that does not mean
you should do it always.

How is "reservation error" different from any other error? What if
drive generates reservation error by mistake?

I believe drive should be considered dead until reboot after
"reservation error". That way you do not damage data by default, and
provide user option with doing whatever is appropriate.
I'm "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at
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