[ubuntu-uk] Software verses Hardware raid (was RE:Anyone evertried kolab on feisty)

[Ian Pascoe]

Hi Alan / Daniel

An interesting topic and one that has recently been done to death on the
Beowulf mailling lists under the "Big Storage" title (sorry, haven't sused
out their archive system yet).  Now these guys are looking at HPC  and HA
computing going up from 4 to 1000+nodes with PB size storage levels.

The conclusion they came up with was that for 99.9% of scenarios hardware
RAID beat software RAID hands down - this was not hearsay but through
experience.

I'm interested in why Daniel chose RAID in a single box as that to my mind
gives you an instant single point of failure - I'm always glad to be proved
wrong!

What will be your backup strategy or are you going to be totally reliant on
RAID for that?

E



-----Original Message-----
From: ubuntu-uk-bounces at lists.ubuntu.com
[mailto:ubuntu-uk-bounces at lists.ubuntu.com]On Behalf Of Alan Pope
Sent: 27 September 2007 16:06
To: British Ubuntu Talk
Subject: Re: [ubuntu-uk] Software verses Hardware raid (was RE:Anyone
evertried kolab on feisty)


Hi Daniel,

On Thu, 2007-09-27 at 15:58 +0100, Daniel Lamb wrote:
> Personally I feel raids only real use is data protection, as hard drives
are
> sometimes very unreliable anyway how is really worried about speed? This
is
> in a server which means its not reading or writing at a very fast speed
> anyway.

Your server might not, but many do. A friend of mine runs a server and
IO is the single biggest bottleneck on the box. He has 4 physical disks
with the data mirrored _and_ striped over them. So he has performance
and resilience.

Of course if the server is only an office server with some documents and
email then it's less of an issue perhaps. It's all about the usage.

Cheers,
Al.