View Full Version : Dual 1Gig 3Cheetahs

07-11-2002, 01:29 PM

I just recieved a BTO dual 1Gig with a dual channel SCSI card and 3 internal Cheetahs.

I would like to format the Cheetahs as a RAID stripe 0 and use it as my boot drive. Has anyone tried this. I am expierencing a few problems. The first is like rhunt000 I found my dual channel SCSI card is an ATTO card with only one internal connecter> the drives came daisy chained to the internal.
The biggest problem I am having is I have booted from my OS X CD and tried to format the drives as a RAID stripe and I am getting an unkown error and the RAID stripe is not being created.
I don't know why this is not working.


07-11-2002, 08:31 PM
There was a KB article recently about not being able to format RAID when booted from the CD.

The ATTO thing is a "known" 'gottcha' - twisting the truth a little. Which is why I'd never go that route and build my own. Guess you can't send it back and get another? Maybe a G4 DDR etc??? (we can hope can't we?). Also, if you're serious about RAID, what about UL4S/D?

Even the Apple price for cheetah is pricey.

07-12-2002, 12:35 AM
Hey FT,

?About the only thing I venture consistently about RAID is that it shouldn't contain your OS volume. Especially in OSX. OSX does way too much housekeeping access to the root volume for a stripe to be efficient. Besides that it just isn't that safe.

?I do have a hardware RAID with OSX Server on it for testing. And I have a hardware RAID on my B&W that contains the only drives on the B&W so I have broken with my own rules somewhat. In both cases though I either don't use the OS except to learn what OSX Server has to offer or the computer itself is just for backing up my Quicksilver and playing a few games on. My serious machine has the OS on ATA100 drives backed up on ATA100 and SCSI drives with scratch on SCSI RAID.

?I can't quit figure out why the BTO ATTO only has a single connection/channel internal and external. Seems a waste and not very cost saving. I don't know what you should do about that either. An external 2 drive enclosure wouldn't be too bad an answer and adding a fourth Cheetah on your UL3D will completely saturate the PCI bus which is pretty cool. I have never even tested RAID0 with an odd number of drives, I'll have to try that. Only problem is you'd have to do the odd number on only one channel and I don't have the cabling to do that.

?Good to see you're still around pushing electrons through Macs.


07-12-2002, 02:23 PM

Well I called my friendly Apple support number and was told to install OS X first on one of my harddrives, boot from the installed OS and then to configure the RAID using the other 2 drives. This did work. I only have a 2 drive RAID but it did work.

This is the safest route since the OS is now out on its own drive. The RAID setup went fine. The only problem now is that I only have a single channel card feeding the drives.

What is the latest the best ATTO card and cabling that I should get? All my Dual 800's are running UL3Ds.


07-14-2002, 05:38 PM
New Macs will not boot from a software based raid anyway so what you were doing would not have worked in any way except the way you did it. (1 boot drive and 2 raid drives)


Damien's Stuff (http://www.macmeisters.com/Damien/)

07-15-2002, 01:09 PM
I found an intersting fact from the Apple tech I was talking with regarding my RAID problem.

OS X ( 10 .1) does not support booting from a RAID set. The indication is that this will be possible in a future version of the OS. How future he was not sure about.

Currently creating a RAID set must be done from an system that has been booted from a harddrive. You can not create a RAID set while booted from an install CD.