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View Full Version : G3 B&W w/Raid 0 -- MacGurus says ??



michaelkirk
12-27-2000, 11:38 PM
Recently, I purchased 6 18Gb cheetas and 2 Miles2 scsi boards to go in two G3 B&W machines 450/400... in my purchase order to macGurus... I spelled outy my plan.. -- 3 drive raid 0 ... in both machines.. nothing extravagant

However... these machines do not recognize a Raid 0 as a bootup device...

Did I miss something...

Here is the apple TLL -> http://til.info.apple.com/techinfo.nsf/artnum/n58258

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Michael Kirk
Philadelphia, PA

[This message has been edited by michaelkirk (edited 27 December 2000).]

magician
12-28-2000, 04:13 AM
it is well-known and documented here in the forums and elsewhere on our site that New World machines cannot boot from striped or mirrored software arrays at this time. While there are some work-arounds, they are not endorsed by Apple, nor by MacGurus.

the correct way to use a RAID 0 in a Yosemite is to boot off a fixed drive, then use a RAID 0 as workspace.

jorge
12-28-2000, 07:36 AM
To harnes the power for OS X, a boot raid will be essential for us power users. They better get on the ball.

j

michaelkirk
12-28-2000, 10:27 AM
I could not find this on the Macgurus site... in any case.. I would have thought that my e-mail order would of set off an alarm.. and you would have advised me otherwise... I also asked this question in this forum setting a while ago.. and did not have anyone say it would not work..

Using the Raid 0 as a "workspace" seems counter-intuitive since softraid recommends to use the Raid0 for applications and raid 1 for critical data... it seems that you would want to use the Raid 0 as a system disk for maximum speed..

I assumed I would get advice during the purchase of stuff of the macgurus site...

I am disapointed about this... I thought Macgurus would differentiate themselves with good tech advice...

Now my plan is to buy a G4 and put this setup into it for video publishing... keep the 2 G3's as MacOSx servers for streaming video and web stuff..

I just need to figure out if the power supply can handle the drives and the video cards..



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Michael Kirk
Philadelphia, PA

Dogstarman
12-28-2000, 02:37 PM
Sorry about the confusion you had, Michael. I haven't had any bad experiences with these folks. I made sure to email them explicitly with a question if I had one. I know there are posts about this issue...and as far as being counter-intuitive? Well, the best amount of speed will be with a RAID-0 for booting, of course. But you simply can't do that. Running apps off of the striped array will speed up your launches, opens and saves a whole bunch. Not to mention having a large striped space for a scratch disk.

And your initial post back in October: Not a soul recommended putting a RAID in the new boxes (Only the coveted 9600). They mentioned an Ultra2/3 card and a drive. Kaye mentioned putting 2 drives on a card, but he also asked for help in making sure it'd work. I think your options are limited at this point. An option is to boot off of a Cheetah and stripe the other 2 for each G3. Or buy a small drive to work harmoniously on the same bus and use it as a bootdisk. I know it is more a software issue than anything. Maybe OSX final release will address this. I heard it was on the "to-do" list. Best of luck from here.

[This message has been edited by Dogstarman (edited 28 December 2000).]

magician
12-28-2000, 05:49 PM
well, for what it is worth, we regret the confusion. I just made a quick sweep of the site, and the information is posted on both our ATTO and Initio pages, but it is buried in the technical notes at the bottom of each page. This obviously requires some careful reading by the consumer, which is not ideal. I looked briefly in the SCSI Pages of Doom, and did not easily find it there, but I am pretty sure I remember mentioning it there somewhere at some point. The key point here is that this information is not readily apparent, not adequately emphasized, and you clearly fell thru the cracks here.

I think what happened here is that we all knew this, and consort regularly with other folks who also knew this, and we mention it, but we don't emphasize it. I can easily understand what happened with any email you may have sent, or if you placed a comment on your order. We scan order comments and configurations for incompatibilities, and if we don't find them, we pass the order along. It is probable that a Guru scanned your order and believed that you knew what you were doing when you ordered. Remember, we do have the most savvy customers in the market here. We are a very good fit for them. As is apparent in this case, we were not a good fit for you, and again, we regret that.

for email, if you posed the question explicitly, it would be answered, assuming of course that we replied to your email. If the question was implicit, we may have missed it. We read far too many emails here, and are working to transition as much of that work to the forums as possible. There are simply not enough of us to go around to support everyone one who needs it--and we're not talking about customers. We talk to anyone. Customers come first, but clearly you were not assisted adequately, and we regret that. While we're not clairvoyant, we are honest, plain folks here. We try to be clairvoyant, but like most mediums, our accuracy is less than perfect.

now, it is, IMO, optimal to boot off a RAID 0 from the standpoint of performance. It is less than optimal to do so from the standpoint of data security. You sacrifice some safety for speed, in other words. If you practice a good backup regimen, and listen to our guidance when you build your array, the odds are very much in your favor. So much so that we all run our vintage machines off boot arrays, and prefer them to new machines for this sole reason.

in a New World machine, you are not supposed to be able to boot off a RAID 0 or RAID 1 volume. We do it all the time, of course, but not on production machines. It is not endorsed or supported by Apple, and so it is not endorsed or supported by SoftRAID. They have not received the sort of support they require from Apple to easily "fix" this, assuming you consider this a problem, or a bug, which Apple does not. SoftRAID has told us that they are working on the problem, and hope to understand it well-enough to support the option in the future.

the current work-around is to ensure that there are no other bootable volumes available to the Mac. That's it. If you have an IDE drive installed, and you run SoftRAID from it and build an array using two or more drives, you can install a MacOS folder on it, along with all your apps, and "force" the Mac to boot from it by selecting it in the Startup Items folder and then removing the IDE drive from the Mac, or by reinitializing it after booting from a CD-ROM or any other volume. Remember: the Mac must not find any other bootable volumes. If you leave a bootable CD-ROM in the machine, it will boot off that. Likewise a Jaz or Zip or Orb or anything else. Only the array can be attached, with a bootable partition. And if you create several partitions, the boot partition must be the very first one made.

when the Mac fails to find any bootable volume where it expects them, it will boot off the array. Since it takes time to boot a New World machine in this way, we leave them up and running all the time. They are wicked fast.

unfortunately since neither Apple nor SoftRAID endorses the practice, we cannot. We have no idea why Apple does not support it, but what really gives us pause, is why Apple would intentionally not assist SoftRAID in overcoming the technical challenges inherent in making it work. Since we are paranoid by nature, and cautious where data is concerned, we feel that there may be a reason behind Apple's stance, one which they may not have shared, or which they may not wish to share. They obviously have not shared it with us, or we would have blabbed it to everyone here by now, or pointedly made the usual "no comment" comment.

yes, this could be classified as hyper-caution. And we do have Sawtooth here booting off RAID 0 at this time. No one can explain to us why it works, or why we shouldn't do it. All we hear is simply, "Apple doesn't endorse it." Well, they don't endorse booting from any array, frankly, as far as we're aware. But we've all been doing it for years now, and we're addicted to the performance boost it yields. And Apple knows this. and even discussed it, at some point, in the TIL. (Which has been rewritten, multiple times, so a search there may or may not yield results at this point).

so there you are.

if you have two drives, then boot off your IDE drive, and put all your apps and your work on the array. Keep redundant copies on your IDE drive for security. If you have three LVD drives, boot off one, and use the other two for your array. This is the endorsed and supported approach.

we have had extended conversations about this on these fora in the past, and I find it hard to believe that no one would explain this if you explicitly asked the question. I suspect it is also posted on the SoftRAID site...ah, yes. I immediately found it posted on their Compatibility FAQ (http://www.softraid.com/compfaqs.lasso#Q9).

unfortunately, we're just people, and so we're as prone to error as anyone else. Again, if you explicitly ask a question, we pride ourselves on direct and terse replies (all evidence to the contrary in this one). FWIW, I'm not aware of any other customer or member of these forums who has claimed that we intentionally misled them. I can assure you that was not our intent.

anyway, all is not lost! You can either try the work-around (not recommended), or simply use SoftRAID as it is currently intended. It is still very fast, and will still dramatically improve your overall performance, even if you are not booting off an array.

michaelkirk
12-28-2000, 06:18 PM
Wow...

World Class responses to a confused customer...

Thanks :-)

BTW.. the 3 disk raid 0 in my 9600/350 boots and rips at 65MB/s reads and 27MB/s writes... I am VERY happy with this setup..

My frustration caused me to go out an buy two new new G4 dual 500 for the Raid's and keep the G3's as single disk scsi units...



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Michael Kirk
Philadelphia, PA

magician
12-29-2000, 12:27 AM
we appreciate your understanding.

http://macgurus.com/infopop/emoticons/icon_biggrin.gif