What do you use?

[Scott Mitchell]

On Thu, Jan 01, 2004 at 01:09:23PM +0000, Francisco Reyes wrote:
> On Thu, 1 Jan 2004, Scott Mitchell wrote:
> 
> > As for RAID, we use Vinum, but only because I inherited a bunch of machines
> > with hot-swap SCSI bays and no hardware RAID.  It works well, once you have
> > it set up, and I've even managed to swap out failed drives without a reboot
> > :-)  I'll definitely investigate the 3ware cards when I need to build a new
> > RAID server, though.
> 
> But wouldn't a 3ware RAID be slower than an SCSI setup? Unless your
> current setup is using old SCSI disks. Also how is the load? Lots of
> simultaneous use or just many quick/small access (ie people using
> documents/spreadsheets).

There no particular reason for an ATA RAID to be slower than SCSI, assuming
similar disks in each.  10krpm 'server class' ATA disks are available these
days, although I don't know that anyone has done a 15krpm one yet.

In any case, performance is only one reason to use RAID.  My arrays are
RAID-5's, serving developer home directories over NFS, and a CVS server
(ie. lots of small file accesses).  The main requirements were to have
some fault tolerance and to get the most out the of disks I could buy with
the available budget - hence the RAID-5.  Read performance is no worse than
with a single disk, and degrades more gracefully with multiple simultaneous
access.  Write performance is pretty awful, but that's the nature of
RAID-5.  No doubt if I had an unlimited budget I would do things
differently, but those days are long gone :-(

I'd also expect/hope that a hardware solution (ATA or SCSI) would be easier
to manage.  Vinum is great, but swapping out a dead drive is still a scary,
multi-step procedure, that I do infrequently enough that it always requires
half an hour with the manual and my notes from last time to make sure I get
it right.  With our Windows servers (Compaq Proliants with hardware RAID),
you just yank the old drive, plug in the new one, and it's done.  I'd love
to be able to do that with the FreeBSD servers as well.

	Scott

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