Re: postgreSQL on NAS/SAN?

On Tue, 17 Jun 2003, Jason Earl wrote:

> Ron Johnson <ron(dot)l(dot)johnson(at)cox(dot)net> writes:
>
> > 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.
>
> I can't speak for everyone else, but I can tell you *my* reasons for
> going with PostgreSQL as opposed to a fancier solution like RDB on
> VMS, or Oracle on Solaris, or DB2 on whatever IBM platform sounds
> interesting today. PostgreSQL does what I need it to do without
> breaking the bank. Sure, it's a little extra work getting PostgreSQL
> to do something like hot failover (or load balancing), but when you
> can't afford the other options you make do with what you have.

Keep in mind, if you need more performance than X86, you can always buy a
used E10K online for ~$24,000 or so (there's one on Eb*y now with 20 400
MHz CPUs for less than that, and it's been coming up week after week with
no buyers.)

Older mainframes are there for $5,000 or so as well.

The linux kernel is supposed to have hot swappable hardware support in it
eventually for both those platforms, so you've got your 24/7 with no need
for a second box. Of course, I'm sure for $5,000 you could afford to buy
two mainframes and fail them over yourself on the one time every fifty
years or so one fails. :-)

I'm certain the license fees for rdb and VMS are no small amount, and with
the E10k or mainframe, you own it outright.