Re: Documentation of big "mail systems"?
On Sat, 16 Oct 2004 02:02, Christoph Moench-Tegeder <email@example.com>
> ## Henrique de Moraes Holschuh (firstname.lastname@example.org):
> > > So, now we would like Russel to explain why he does not like SAN.
> > He probably doesn't advocate using SAN instead of local disks if you do
> > not have a good reason to use SAN. If that's it, I *do* agree with him.
> > Don't use SANs just for the heck of it. Even external JBOD enclosures
> > are a bad idea if you don't need them.
> Of course. Buying SAN for a single mailserver is not worth the money.
> Think of money per gigabyte and the extra trouble of managing your
> SAN, local disks are much easier to handle.
Getting servers that each have 200G or 300G of storage is easy. Local storage
is expected to be faster than SAN (never had a chance to benchmark it
though). Having multiple back-end servers with local disks reduces the risks
(IMHO). There's less cables for idiots to trip over or otherwise break
(don't ask), and no single point of failure for the entire network. Having
one back-end server go down and take out 1/7 of the mail boxes would be
annoying, but a lot less annoying than a SAN problem taking it all out.
For recovery I would prefer to have a spare system and hot-swap disks. If
there's a serious problem then swap the disks into an identical machine
that's already connected. Down time is the time taken to get a taxi to the
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