RAID for Zero-G? 123
Cujo asks: "In all seriousness, I need a RAID that supports at least level 3 and stores > 500 GB, and I need to it work in zero-G (but not in a vacuum), and be able to take a fair bit of vibration and noise when turned off. I don't want to spend huge sums: I'm thinking well less than $50,000. I've looked at Apple's XServe/XRaid products, and they look great (about $10,000), but are they rugged enough and who is their competition? Some people make hardened RAIDs for military use, but I'm unfamiliar with the best candidates in that field (and do I really need mil spec?)."
Have you tried IBM? (Score:5, Informative)
Re:I don't have an answer, but... (Score:5, Informative)
Shuttle middeck. It's an environment beningn enough for humans, so not as bad as an ELV ride. The drives would be off and parked during ascent.
Heat and Radiation (Score:5, Informative)
- Heat
- Air pressure
- Radiation
Testing tip:Convection cooling gets assumed into almost everything, so you'll have to make sure the gear gets some air forced over everything to keep it cool. Inside the hard drives, you've got those nice platters pushing the air for you, so that should be ok.
You indicate that there will be air, but not the pressure. You should test your system at the operating atmosphere and pressure for an extended amount of time. This is critical because the hard drives typically float on a cushion of the ambient atmosphere.
Since you're outside the 50 or so miles of air which filters out most of the radation common in space, make sure you have hardware ECC RAM, etc. It would also be good to make sure there is a hardware watchdog in place to protect the OS from hanging do to an induced CPU error.
I'd suggest you test the unit, then run the same test with the unit operating upside down, and on each of it's other 4 faces, as a minimum.
You've got an interesting project, good luck!
--Mike--
You may want to talk to these guys (Score:5, Informative)
ATTN: Paul, got some contacts (check your e-mail) (Score:2, Informative)
You'll need SCSI (Score:3, Informative)
The other reason you want SCSI is reliability. That's one of the reasons SCSI drives are so much more expensive. I've seen more than one SCSI drive get dropped on a hard tile floor and still be usable for a year or more (These are half hieght Seagate and IBM, 7200 or 10k RPM, YMMV).
If you do decide to go IDE, try to use laptop drives. They have MUCH better g-force tolerance than the standard 3.5 inch IDE drives. However, I've still never seen one survive getting dropped on a hard tile floor. Shock and vibration are different things, though, so the laptop drives still may be a better choice. You can
You could go flash, and that would take care of the vibration/shock issue, but at 1GB each that's an assload of IDE controllers you have to somehow get working together. Assuming 4 per controller, that's still 125 controllers. Even if you solved the IRQ problem, where would you put all of them? Space is a precious comodity on these missions. Plus at $200 each that means $100k for 500GB, which seems to be out of your budget range. A custom motherboard with 125 PCI slots is certainly out of your budget range.
What I would do is talk to standard RAID vendors like EMC^2 or Ciprico and see what they've got. I know a company that would be happy to design and build a shock-mount for a standard raid chassis for you for probably under $10k. You could also go somewhere like Musicians friend and buy a road case, which will certainly have some anti-shock measures, for a few hundred dollars if your needs won't be too severe.
I very much doubt that zero-g will be an issue at all. The things that will be problems have already been mentioned by other posts.
Re:Zero-G likely matters not (Score:3, Informative)
been there done that. (Score:1, Informative)
2 x 533Mhz Alpha 21264As (164LX boards) with 1Gb RAM (ECC) each, RAID-5 using ICP-Vortex boards with 128MB ECC cache RAM each and 7 x Maxtor 120GB HDDs with hot swap PSUs. systems mirrored each other, so there was 400GB of usable space (roughly, 2 hot space + 1 checksum drive). total cost was around $10K including custom parts (boxes, power distribution, batteries, etc). All usable space in the inside of the boxes and RAID towers was filled with DuoFoam (Its the spray can thingy which expands into rubbery yellow foam in contact with air. Systems were shutdown on the ride up, switched on in freefall and shut down for the ride down.
2 hard drives failed during the entire trip, one of the alpha CPUs has its heatsink warped by heat and some foam had melted off. all the data was ok, though.
Re:Zero-G likely matters not (Score:3, Informative)
They cannot have a vacuum in them, as the head gap is created by the bernoulli effect, and without it, the drive would quickly destroy itself!
Re:Scary (Score:1, Informative)
Dear Leroy,
I'm sorry, but the pain will keep getting worse until the hatching. Don't worry - you still have a few months to live, as it avoids eating the vital parts of the brain until near the very end.
May I suggest making the most of it, and traveling to nations you don't like, in the hopes that the hatchling stays away from people you care about?
- Mad Scientist # 28
{*}
Macs in spaaaaaaaaaace.... (Score:2, Informative)
Cooling the units shouldn't be an issue, the fans are powerful enough that in null gravity they'd be able to propel the unit:)
And, i know that at least one company was planning on using G4's in space, so there should be some studies on radiation effects and such on those processors floating around somewhere....
Comment removed (Score:2, Informative)
Re:I don't have an answer, but... (Score:3, Informative)