Cheetah SCSI's

[Asr940]

I have a chance to pick up six Seagate Cheetahs, model #ST173404LC for about 80 bucks. I am pretty sure they are 10k Ultra 160 drives.

I was wondering if these were worth it as a raid array?

Also, if these would be a good deal, can anyone recommend a SCSI controller card? Preferably Raid 5 compattible.

[leojharris]

if you can get all six drives for 80 dollars ... then hell yeah it's a good deal; a single drive sells for around 75 bucks as it stands.

those drives would smoke if set up as a RAID system ...

as far as controllers ... no reason to look beyond adaptec ... although, for a decent RAID controller you'll have to drop a little change.



I have a chance to pick up six Seagate Cheetahs, model
#ST173404LC for about 80 bucks. I am pretty sure they are 10k Ultra 160 drives.

I was wondering if these were worth it as a raid array?

Also, if these would be a good deal, can anyone recommend a SCSI controller card? Preferably Raid 5 compattible.

[ErikD]

At $15 a drive that is not a good deal. Its a great deal! As long as they are working of course. I just paid close to $25 a drive for the same drive but 36GB model and was pretty happy (also got 6 of them).

As mentioned a good controller will set you back some. I am stuck with a crummy older controller that does all the RAID functions, but is beat out by even a single IDE drive.

[emboss]

They're fairly old drives, circa 1999. But not so old that $15/drive isn't a steal :)

Note that these also have a SCA cannector, so you'll either need to pick up an enclosure with a backplane or 6 of the 68-pin to 80-pin converters.

[Asr940]

Thanks for the info. It is much appreciated. I did a bit more research on my own and decided not to go with them. Too much of a hassle/cost with controller cards and etc.

Perhaps I will try going with something similar in the future though.

[emboss]

SCSI is a dangerous thing to get into: far too many really nice things going on ebay for just a little bit more than what you'd like to pay for a "toy" :) I'm only just trying to resist from buying a new RAID card at the moment ... and once I do that I'm going to need more drives to let the card really get into it's stride ... and then I'll probably need to upgrade the stuff around the box to be able to fully benefit from the box ... and then etc etc.

As soon as you start playing with "enterprise" stuff there's ALWAYS a bigger, faster thing out there just waiting to be bought!

[Moto7451]

I like ATTO SCSI cards. They always seemed to work better in my Macs than Adaptec did and performed better.

[Asr940]

Yeah, I know. Like Optys.
The more I read about SCSI, the more I like the idea. :drool:

Oh, got another question, I assume that ultra 320 cards are not backword compatible with U160?

[dark_15]

Yeah, I know. Like Optys.
The more I read about SCSI, the more I like the idea. :drool:

Oh, got another question, I assume that ultra 320 cards are not backword compatible with U160?
Actually, most are. Always check the documentation first, but in most cases U320 Cards are backwards compatible with U160 drives.

[Asr940]

Thank you. Nice to know. Got to keep my eyes open.

[Xaotic]

Be careful, some of the 1 series driver were U2W and performance would be very bad in that case. They should be U160, but verify before purchase.

These are SCA drives and you will either need a backplane or adapters. Add about 15.00 each in terms of operational cost.

These are half height drives. They are the 1.6" drives and about as tall as an optical drive.

They will be HOT and LOUD. Plan on active cooling and preferably remote mounting the system they're in.

Now for the bad news... Any RAID controller that will give decent performance will be incredibly expensive. Most of the U160 controllers will have decent reads, but the writes will be abysmal.

Though they'd probably be nice for bragging rights, you could almost certainly completely obliterate the performance with a pair of 7200.10 320s on an onbaord controller.

If you really want to go SCSI with these, then find either a LSI MegaRAID or IBM ServeRAID 4 controller, preferably at least 2 channel to eliminate channel contention issues.

[emboss]

Now for the bad news... Any RAID controller that will give decent performance will be incredibly expensive. Most of the U160 controllers will have decent reads, but the writes will be abysmal.

Though they'd probably be nice for bragging rights, you could almost certainly completely obliterate the performance with a pair of 7200.10 320s on an onbaord controller.

Depends largely what you're doing with it ... on random-access workloads, the Cheetah's would destroy the 7200.10's. STR would be another matter (but STR isn't really SCSI's forte anyhow).

If you really want to go SCSI with these, then find either a LSI MegaRAID or IBM ServeRAID 4 controller, preferably at least 2 channel to eliminate channel contention issues.

Personally, I'd say stay clear of the ServeRAID 4's. They're very picky about what motherboards they'll work well with. Unless you put them in a IBM server they tend to either hang during POST or work very slowly. My personal favourite cards are the Compaq SmartArray 5300's or 6400's (the former being pretty cheap, and the latter being rather more expensive). A SA 5302 will beat out a MegaRAID 1600 in most cases, with the main problem being that it's a full-length PCI card and that the controller needs some fresh air or it will run hot.

[dmitryk]

Just FYI. It is very hard to find good SCA to LVD (80 to 68 pin) adapters. A lot of them do not follow signaling specification and you will wind up with very poor speed. e.g. Startech. Drives will be recognized but not anywhere near to Ultra 160 speed. Backplanes usally won't have that issues.

[Asr940]

Thanks for the note on the converters, also, do backpanes run on an individual cable per drive? or one cable for group of drives? If it is one cable per group of drives, does performance drop from that?

"My personal favourite cards are the Compaq SmartArray 5300's or 6400's"
Thanks for the suggestion. Doing some looking

[dmitryk]

do backpanes run on an individual cable per drive? or one cable for group of drives? If it is one cable per group of drives, does performance drop from that?

They are connected one cable per group of the drives. Each drive is connect through SCA connector with backplane which then route the signals.

SCSI is designed that all drives connected by means of one cable to Host Bus Adapter. No speed decrease occur because of that.

[Asr940]

"No speed decrease occur because of that."

Thank you, I have only ever worked with IDE raid, and when I did there was a definite drop in performance with RAID 0 on the same channel.