In article <pan.2004.11.17.02.21.35.312789@dcs.nac.uci.edu> , Dan Stromberg <strombrg@dcs.nac.uci.edu> wrote:
>
> Does IBM have a storage solution with the following attributes?
>
> 1) Can store at least 30 terabytes, with a single, unified namespace
>
> 2) Costs between $50k and $200k
>
> 3) Doesn't have to be blazing fast. In fact, a tape jukebox or HSM might
> be acceptable, though so far we've only discussed RAID systems.

For disk systems, I don't think you're going to find an IBM product for
30 TB at $200K. 10-12 or 15-18 TB at $200K, maybe.

(I haven't talked with our IBM VAR for a disk quote lately, so I could
be wrong! But judging from specs of the current DS model lines and past
experience with FAStT pricing... that's my ballpark guess.)

One option to get 30 TB+ at $200K and still have future expansion
capability if you'd consider high capacity modern tape libraries would
be to buy an IBM 3584 LTO-2 tape library or maybe the smaller 3583.

A single LTO-2 tape stores 200 GB natively, 400 GB with hardware
compression -- and I must say that this is a very reliable number.

We actually average about 2.24:1 with hardware compression enabled on
our LTO-1 tapes and have some occasional spikes to 3.8:1 but no less
than 2.0:1. I can't imagine this being any different with LTO-2.

Speed is pretty good; up to 35 MB/sec natively and up to 70 MB/sec with
hardware compression enabled for LTO-2 -- assuming that you can pump
disk and network data to tape that fast!

The tape cartridges are the same form factor as DLT, if that helps
visualize its size/weight.

Each LTO-2 tape is about $200 at IBM's list price, and perhaps $150
after a typical discount, and maybe a little cheaper elsewhere.

Drive is usually the most expensive single part... probably about USD
$18K or so, but unless you need many of them, that's not a bad solution
for nearline storage + large capacity.

We're very pleased with our 3584 LTO tape library and use IBM's TSM
(Tivoli Storage Manager) to manage it. Piece of cake, though there's a
slight initial learning curve in getting used to TSM.

The LTO libraries makes it easy to manage because they have pretty good
remote management features (eg built-in robot), have barcode scanner
inside, can move tape from any part of the library to any drive or slot
or I/O station (door), etc. I've done remote installs of 3584 libs from
2,000 miles away, no problem. :-)

The 3583 is physically somewhat smaller; maxes out at 6 drives (but can
have as few as 1 installed) and a max of 72 tapes. That wouldn't leave
you with any real future expansion growth path if you ever needed to go
past 30 TB over time. I'm not sure if it's got a robot internally.

TSM also comes with HSM features which makes it possible to have
online/nearline/offline/etc type of data migrations, and supports all
sorts of stuff -- disk-based storage pools, tape-based stgpools, even
CDs, and whatnot.

> Does this solution support 251G SATA drives by any chance? We have a lot
> of them from something else.

Alternatively, if you really need cheap but high capacity disk
enclosures with reasonable support and decent pricing, check out
Jetstor from AC&NC.

http://www.acnc.com

We've got units from them and have been very pleased with setup,
operation, support, maintenance, replacement, etc. Some pretty large
shops uses them too, from what I understand. AOL and some other places?

Anyway, AC&NC has an array of models... my pricing is a little old since
there are newer/better models out now, but it was ~$12K for an enclosure
with 14 ATA disks and a SCSI attachment to the host... $22K for an
enclosure with 12 10K RPM SCSI disks and a FC attachment to the host.

I know they've got SATA models -- where it uses SATA disks and offers
either SCSI or FC attachments to the host's HBA.

Its competitor, which we also evaluated, was Nexsan, with similar
products. Pricing was close although a little off... their support was
ok, but could use a little improvement in some places. Probably couldn't
really go wrong with them, though, either.

http://www.nexsan.com

Finally, there is also an option of getting a 3ware disk array unit +
controller. That combo is what some vendors actually use behind the
scenes (eg rebrand) for their own disk arrays!

3ware makes very, very good stuff... though some sites are reluctant
(understandably so) to go with a 'roll your own' solution without tech
support overseeing the whole setup and 24x7 availability of replacement
parts, etc. But thought I'd at least point out this option.

http://www.3ware.com

Now, a disclaimer... I work for *none* of these companies or any
resellers. I speak only as a satisfied customer and as an evaluator.

We have quite a few disk systems, including IBM's ESS ("Shark"), IBM
SSA, IBM SCSI (eg 2104), Sun arrays, EMC, HDS (Hitachi), amongst other
things.

Anyway, I hope others will pipe up with other opinions or suggestions.

-Dan