More on vinum woes

[Matthew Dillon]

:
:Dave Hayes wrote:
:
:>Might I ask the exact model number of the 3ware card(s) you use for
:>RAID 5? If I do things this way I've got to buy two at the same time,
:>and I'd like to be accurate. ;)
:>
:I've used two 6400 and one 7800 and I can only recommend AGAINST them.
:Out of those 3, two (one 6400 and the 7800) kept kicking out drives out
:of arrays for no understandable reason (means you could rebuild the
:array with the very same drives after that only to have it kick out
:another drive soon thereafter).
:
:For cards, that cost 500$, that's simply inacceptable to me. And the
:support didn't even answer any mails and searches on Google showed I'm
:by no means alone with this issue (and others didnt get any help from
:3ware either, aside of a few that were being told to dump the NVRAM of
:the controller but usually without a howto...).
    
    Its going to depend on how old the drives are, for PATA IDE.  It's
    only the last few years where PATA IDE drives have settled down into
    a semblence of a reliable interface standard from the drive side, but
    even then I wouldn't trust PATA (parallel ATA, i.e. standard IDE cable)
    for *anything* that needed serious uptime.  SATA is different, however.
    At least on the drive side its completely different.  On the motherboard
    chipset side its still a mess because the idiots are trying to maintain
    compatibility with the basic IDE chipset protocols, which have been
    broken from the day they were introduced.  But a 3ware SATA card will
    bypass that so it shouldn't be a problem.

    Everyone I know who was using SCSI for reliability 5 years ago is now
    switching to SATA, simply because they can no longer justify the
    ridiculous price premium for SCSI.  Nearly all the RAID storage vendors
    now have SATA/IDE-support precisely due to this change in the demand
    curve.

    $500 is the cost of an 8-port (900 series) SATA RAID controller.  If
    I have 8 SATA drives $500 would be a small price to pay to build a 
    reliable storage subsystem out of them, especially considering that it
    would cost an extra $1000 if not more if those were SCSI drives instead
    of SATA drives.  I'll price it out for you right now:

	Maxtor 250GB SATA drive:	$100
	Seagate 250GB SATA drive:	$112

	Seagate cheetah 300GB HD:	$900
	Maxtor 300GC SCSI 10K rpm:	$1095

    See the problem?  And that's after spending 30 minutes trying to find
    SCSI drives on the net.  I don't even believe those prices... I KNOW I
    can get better prices then $900 for a 300GB SCSI drive, if I spend
    another hour looking.  When I researched SCSI drives last year they
    were costing about 100% premium.  Now the best deals I can find are in
    the 200% range, or worse, and fewer vendors sell them.

    There's no point buying SCSI any more when you can buy a second 
    (or third) entirely redundant RAID array full of SATA drives for the same
    price.  If SCSI only cost, say, a 20% premium, I would probably 
    still be using it.  But it doesn't.   Even the best deals the premium
    often exceeds 100% and short of spending a lot of time working at it
    they generally exceed 200%.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>