On 2008-04-20, Bruce Esquibel <bje@e4500.ripco.com> wrote:
> DoN. Nichols <dnichols@d-and-d.com> wrote:
>
>> When withdrawn, the drives do not give the typical inertial
>> behavior of a spinning drive.
>
>> I'm reluctant to bring the system down to the OBP level and run
>> probe-scsi-all, because my wife will be using it (the Sun Fire 280R is
>> our file server) even if I will be over at the console looking at the
>> results of the probe-scsi-all.
>
>> A search through google found at least one maker of PC boards
>> for driving FC drives which offers a special card to go between the
>> drive and the fc card to make a "12V Only" drive work when it otherwise
>> will not work.
>
>
> Well, might be time to send the better half out to the movies and check it
> with the OBP but I still think you have a couple door stops.
You know -- I think that it has probably been fifteen to twenty
years since we last saw a movie. I think that it was "Gremlins". :-)
> Seagate appears to have buried or taken offline the white papers and
> engineering stuff, but when this "12V only" subject came up before there was
> a document they had available for the FC drives which broke down all the
> options and variations in that line (guess its Cheetah, 10k, FC).
Yes -- that is precisely what it is. ST3145807FCV
> There
> wasn't a single one made that was 12V only, they all used the split 12v/5v
> for power.
Interesting -- since the label says (in the finer print to the
right of the bold-print ST3145807FCV:
VDC Amps
+5 -
+12 1.4
so at least the label seems to think that it draws nothing from the +5V
pins.
If I had a spare connector pair to match the 40-pin SCA style
connector, I would try hooking it up and using a clamp-on ammeter to
verify whether this is truly so.
> A while back I ran into the same thing, some ebay specials for 18GB's (which
> were twice as expensive as what you paid for the 146GB,
Ouch!
> figure the timeline
> out yourself) and they too had that sticker or imprint on the label.
>
> We contacted the place they came from and they said (we took it with a grain
> of salt) that they got them from a place that built disk cabinets which were
> universal, sort of. They had their own internal non-standard bus and
> supplied the appropiate carrier (spud bracket) to adapt whatever kind of
> drive to it. So with minor changes to the back plane, the same cabinet could
> be used for FC, scsi sca or plain old scsi drives.
Hmm ... sort of useful cabinet, if it it turned out to be
reliable.
> The reason the drives were marked 12V because of this was some OTHER drives
> made by maybe fujitsu or hitachi did in fact use 18 or 24v for the motor/arm
> supply (still 5v for the logic) and those cabinets were not to be used with
> the 12V drives.
Interesting. Reminds me of my first personally owned Sun -- a
2/120. It used a MFM (or was it ESDI) disk with a controller board to
turn that into SCSI. And -- it used an open-frame QIC style tape drive
for loading the OS and for backups. Both used the same connector (the
common +5V/+12V D shaped nylon connector still used on 5.25" and 3.5"
drives -- but the connector to the disk drive had 24V in place of the
12V - no such thing as using a different connector to prevent frying
drives by mixing them up. :-)
> Yes I know, it would make more sense to mark the cabinets "18V drives only"
> but this is what they told us.
What would make even more sense would be to key the connectors
so you could not plug the 12V drives into the 18V backplane. :-)
> I don't know what you found on google about this adapter but my guess is
> it's along the same lines. I'd say it's more likely there are some host
> adapters out there that used it, not the other way around.
Folded URL to the item which I found, FWIW.
http://store.ckcomputersystems.com/i...roduct_info&c\
Path=1_9&products_id=219&zenid=47fb1910dc4cf0e9f12 58b40c230ef88
Interesting that this thread is what comes up at the top on the search
today. :-) The search string on Google is:
How to "12V ONLY" (FC,"Fibre Channel")
The next hit of interest is:
http://www.fold4life.com/forum/viewtopic.php?f=5&t=1051
But it is pretty useless other than to confirm that someone else has
some "12V ONLY" drives -- and fairly recently -- 18 March 2008. :-)
> Anyway, the 18GB drives marked "12V only" worked just fine in a A5200
> cabinet so I'd say they should work in the 280R as well.
Well ... both don't work in the EMC/Criiterion cabinet, and the
only one which I tested directly in the 280R also did not work. I guess
that it is time to upset my wife and bring the system fully down and
test both drives at once.
The EMC cabinet is old enough so it only supports the 1 GHz
Fibre Channel, but the drives are supposed to be able to switch, and the
internal card cage should handle it as well.
A pity that the 280R won't accept the 1.6" high drives that the
SB-[12]000 will.
> If you don't think the motor is spinning up at all, that really is the kiss
> of death I think. A bad firmware update can cause that but I never found a
> way around it. Probably needs to go into a manufacturing mode using some
> magic cable or secret combination of jumpers.
Since these were two of something like 58 drives that the vendor
had -- either his source zapped them all, or there is something else
wrong.
Given how low the price for the "12 ONLY" fix that the offer, I
could believe that it could be something as simple as a resistor to draw
current from the 5V line to convince the port switching that there was a
drive there to talk to.
> Still, I admit I can be wrong about all of this but after taking advantage
> of several "ebay lots" over the past 6 or 7 years, I don't think so.
Most of them work out -- but not all. A pity that I don't have
a single drive chassis for FC so I could power up the drive and feel for
gyroscopic effects while measuring current drain.
I presume that contacting Seagate won't do much good? :-)
Thanks much,
DoN.
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