Re: postgreSQL on NAS/SAN?

On Tue, 2003-06-17 at 12:05, Michael Meskes wrote:
> On Tue, Jun 17, 2003 at 03:41:45PM +0200, Daniel Seichter wrote:
> > I am looking for a hot spare, so if one server crashed, the second will
> > "spare" it, because if this database will be down (down is meant for longer
> > than 2 hours) more than two other databases will not continue working (they
> > could continue working, but without new data, so it will be senseless).
>
> Not sure what you mean. Shall the second machine take over? Since this
> should be hot 2 hours is a lot of time. Using a private network you can
> detect failures almost immediately.
>
> I do recommend a a local checking like watchdog or mon, so a restart is
> tried before the takeover. And I'd make sure the primary machine stays
> down.

This is going to sound bad to users of Open Source OSs and databases,
but for all work that has to go into clustering machines and making
databases work with them...

Why not use a clustered-by-design OS like VMS?  It is very easy to
put a couple of dual-Alpha boxen cluster-connected via fiber to SCSI
devices.  A cluster-aware relational database like Rdb runs on all
nodes of a cluster in a totally shared-disk environment.  While both
nodes are working fine, half of the work goes to either node, and if
one node goes down, the other node still does all the work.

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