LinuxQuestions.org
Visit the LQ Articles and Editorials section
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Hardware
User Name
Password
Linux - Hardware This forum is for Hardware issues.
Having trouble installing a piece of hardware? Want to know if that peripheral is compatible with Linux?

Notices



Reply
 
Search this Thread
Old 04-02-2004, 08:27 PM   #1
Jestrik
Member
 
Registered: Dec 2003
Location: Hampshire, UK
Distribution: gentoo, Debian Sarge, Slack 9.1
Posts: 206

Rep: Reputation: 30
SCSI SCA controller card


I have just bought 6 seagate SCSI hard drives, they are SCA (80 pin), 4.5gb each and 10krpm. I am looking for a SCSI controller card for these hard drives. I am not sure as to what I supposed to be looking for, would someone be able to point me in the right direction? With it being SCSI, I should expect any SCSI controlller to work under linux right?

Cheers for any help

I'm a SCSI ...
 
Old 04-02-2004, 09:29 PM   #2
michaelk
Moderator
 
Registered: Aug 2002
Posts: 12,175

Rep: Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784
I would get a SCA 80 pin to 68 pin adapter. I've had sucess with Adaptec, Tekram and Atto SCSI controller boards. Tekram and Atto provide linux support and I've never had any problems using either one. I do not know about the latest Adaptec controllers.

Keep the SCSI cables as short as possible. Make sure you terminate the chain and configure the SCSI IDs correctly. Not sure what your end goal is but you might want to try configuring a hardware RAID if you purchase a controller with such or use LVM.
 
Old 04-02-2004, 10:25 PM   #3
rnturn
Member
 
Registered: Jan 2003
Location: Illinois (Chicago area)
Distribution: Red Hat (8.0), SuSE (10.x, 11.x, 12.2, 13.2), Solaris (8-10), Tru64
Posts: 982

Rep: Reputation: 53
Re: SCSI SCA controller card

Quote:
I have just bought 6 seagate SCSI hard drives, they are SCA (80 pin), 4.5gb each and 10krpm. I am looking for a SCSI controller card for these hard drives. I am not sure as to what I supposed to be looking for, would someone be able to point me in the right direction? With it being SCSI, I should expect any SCSI controlller to work under linux right?
The SCA drives are typically found in hot-swap enclosures (in my experience). But that doesn't mean you can't run them in a garden-variety tower case. You will need to pick up some 80-pin-SCA-to-68-pin-singled-ended converters and a cable with seven or eight connectors. You can get cables that have built-in terminators (usually active terminators) in whch case you could get by with seven connectors (six for the drives and one for the controller. Some of the 80-pin-to-68-pin adapters include a jumper that provides active termination as well. If neither is the case, you can get a terminator that you can attach to an eight connector cable (controller, six drives, terminator). The devices on the ends of the cable need to provide termination. The controller normally provides it as does the last device on the cable. If you connecting something to the external connector of the controller, the controller must not provide termination; only the last devices on the external chain and the last device on the internal chain.

Another option would be to run these in a separate enclosure with drive bays that take the SCA drives directly. An expensive way to go. On the other hand six 10K rpm drive will generate more than a few BTUs. An external case might provide better cooling for the disks than sticking them in the same case as the CPU and other devices. Unfortunately, now you're getting close to the US$1K range.

The 80-to-68 pin adapters run about US$25/ea. (sorry, I'm too lazy to look up the current exchange rate). A seven-connector ribbon cable runs in the neighborhood of US$20 - US$40. A decent controller for drives like these? I'm using an old Adaptec 2940UW with a bunch of 9GB Cheetahs (pretty similar to yours I think). Works just fine. But, those cards are pretty old. You can get an OEM version Ultra160 card (AHA29160) for about US$100. Probably cheaper if you hunt around. That's still not the latest controller available but an Ultra320 card would be massive overkill for those disks. Of course, if you want to plan for the future... :-)

Just outta curiosity, what model drive are these Seagates?

Cheers,
Rick
 
Old 04-03-2004, 04:01 AM   #4
Jestrik
Member
 
Registered: Dec 2003
Location: Hampshire, UK
Distribution: gentoo, Debian Sarge, Slack 9.1
Posts: 206

Original Poster
Rep: Reputation: 30
They are ST34502LC's. So would I need to buy 6x 80-68pin convertors to connect to a SCSI cable? Would an Ulrta320 card support my 6x hard drives?

My original plan was to put them all in a PowerEdge 2400 but I lost the bid on ebay so i'm a bit stuck. I was going to have them in raid5. I was wondering, how fast would this have been? what does btu mean?

Cheers
 
Old 04-03-2004, 08:45 AM   #5
michaelk
Moderator
 
Registered: Aug 2002
Posts: 12,175

Rep: Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784Reputation: 784
I'm assuming:
BTU - British Thermal Unit, a measurement of work.
one BTU is the amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit.

Shouldn't have any problems with a an Ultra320 controller. A dual channel card is capable of connecting 30 devices.
 
Old 04-03-2004, 12:03 PM   #6
rnturn
Member
 
Registered: Jan 2003
Location: Illinois (Chicago area)
Distribution: Red Hat (8.0), SuSE (10.x, 11.x, 12.2, 13.2), Solaris (8-10), Tru64
Posts: 982

Rep: Reputation: 53
Quote:
So would I need to buy 6x 80-68pin convertors to connect to a SCSI cable?
Yes
Quote:
Would an Ulrta320 card support my 6x hard drives?
Easily. Make sure that the card and any SCA adapters you pick up are compatible. Some of the adapters won't work with LVD devices..
Quote:
My original plan was to put them all in a PowerEdge 2400 but I lost the bid on ebay so i'm a bit stuck.
Too bad. Nice system from what I hear.
Quote:
I was going to have them in raid5. I was wondering, how fast would this have been?
With a good controller, you'd barely notice any RAID5 write penalty. I'm using some older Seagates (ST19171WC) drives in a Compaq drive enclosure and configured them as RAID5 off an AHA2940UW. I'm happy with the performance. Your disks are a generation newer; they'll work just fine.
 
Old 05-17-2004, 11:38 PM   #7
synpse
LQ Newbie
 
Registered: Mar 2004
Location: Pennsylvania
Distribution: CentOS
Posts: 28

Rep: Reputation: 15
This is quite similar to my current setup. Nine 18gb Seagate Cheetahs in a tower case and Six 9gb in the hot-swap panel. Adaptec 2940UW to the case, on a Dell PowerEdge 2300. The Cheetahs get really really hot, so it's down right now til there is more cooling. Much Much more cooling. The SCA-68pin adapters can be had for less than $5 on eBay. I used 9 of them, and 9 hard drive 5.25" mounting brackets for $1 apiece, and the Adaptec 2940UW for $25 w/ shipping. The hard drives (9 x 18gb cheetahs) were less than $200 total. So as soon as this heating/hanging issue is taken care of, we'll have a great dump / tape backup machine. I was running backups using NFS, but it's not the best idea. The copy-then-tape idea is much better.
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
scsi controller card recommendations zajelo3 Linux - Hardware 3 09-18-2005 01:12 PM
Megaraid scsi controller card jmarsh Linux - Networking 6 02-01-2005 10:31 AM
hot swap SCSI SCA bus transients harmful to non SCA drives? bdp Linux - Hardware 4 01-29-2004 01:47 AM
adding new scsi controller card chanys Linux - Hardware 6 05-04-2003 06:12 PM
scsi megaraid controller card jmarsh Linux - Hardware 0 04-14-2003 09:07 AM


All times are GMT -5. The time now is 01:09 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration