From owner-freebsd-questions Mon Aug 9 12: 6:27 1999 Delivered-To: freebsd-questions@freebsd.org Received: from panzer.kdm.org (panzer.kdm.org [216.160.178.169]) by hub.freebsd.org (Postfix) with ESMTP id CECFE14D4E; Mon, 9 Aug 1999 12:06:19 -0700 (PDT) (envelope-from ken@panzer.kdm.org) Received: (from ken@localhost) by panzer.kdm.org (8.9.3/8.9.1) id NAA29799; Mon, 9 Aug 1999 13:04:00 -0600 (MDT) (envelope-from ken) Message-Id: <199908091904.NAA29799@panzer.kdm.org> Subject: Re: External RAID boxes (was Re: AHC errors. Bad disk or bad firmware, or bug in driver ?) In-Reply-To: <3.0.5.32.19990809141220.01086510@staff.sentex.ca> from Mike Tancsa at "Aug 9, 1999 02:12:20 pm" To: mike@sentex.net (Mike Tancsa) Date: Mon, 9 Aug 1999 13:04:00 -0600 (MDT) Cc: scsi@freebsd.org, questions@freebsd.org From: "Kenneth D. Merry" X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Mike Tancsa wrote... > At 11:28 AM 8/9/99 -0600, Kenneth D. Merry wrote: > >Yeah, I understand, it takes a while to upgrade. > > > >As far as RAID boxes, I'm not sure I would recommend anything, because I > >don't have any direct experience with external RAID boxes. > > > >I will throw out a couple of things, though: > > > >- Charles Sprickman has had a fair bit of trouble with > > multiple channels on a single CMD array. I'm not sure whether he is > > still having problems. > > > >- On the other hand, Karl Denninger , has had good > > success with CMD controllers. > > > >- ftp.cdrom.com uses a Mylex external RAID controller, and I think other > > folks have gotten good results with them as well. For a small caveat > > (i.e. you shouldn't normally run into this problem, but you could) see > > my mail exchange with Joe Greco from early July. Just search for > > "DAC960SX" and you should see it. The bug in question was a FreeBSD bug, > > not really a bug with the controller. > > > >- I've seen various people mention other external RAID controllers on the > > lists, but I can't remember which. I'd suggest looking through the > > freebsd-scsi archives. > > > >I've never heard of a Legacy RAID box. Does the 5-6K include the drives or > >not? And 8 gig drives? One thing you don't want to skimp on is drive > >quality...most 8 gig SCSI drives I remember seeing are pretty low-end. I > >would recommend sticking with high-end Seagate or IBM disks. > > The exact price was $4700 Canadian, and then they wanted to charge me about > $900 CDN per Segate Medalist or $1000CDN for I think the IBM Deskstar. So I > guess, ~6500 USD with 5 drives Hmm, it sounds like they're going with low-end drives. I'd stay away from the Seagate Medalists, we've got quirk entries in the CAM transport layer to attest to the firmware "quality" on the Medalist Pro. I'd go with the IBM Deskstar, although I can't guarantee they're good, there's probably a better chance of their firmware being okay than the Seagate Medalists. Most likely they've qualified both types of drive with their hardware, and therefore they're sure those drives will work. > >You'll want something that does tagged queueing, and handles a reasonable > >number of transactions. And, most importantly, you'll want a controller > >without nasty firmware bugs. :) FreeBSD/CAM has a tendency to expose > >problems that don't crop up as often in other OSes. > > Before making any commitments, I do plan to dejanews through as many > threads as possible. The legacy (www.legacy.ca) box looks nice in that > the warrentee is decent (overnight replacement from down the road from us > for 3yrs), and the price seems nice. But stability is what I am looking > for most of all. +-$1K at that range is not that critical.. stability is > the key for me. I am not sure what I would end up paying for in the equiv. > Mylex device. Yes, I think stability is very important. I would be slightly concerned with Legacy's choice of drives. More important than that, though, is how good/stable the firmware on their RAID controller is. i.e. how they handle under load. If you want to go with that solution, you may want to try to get an evaluation unit first, so you can subject it to a higher than normal operating load and see what happens. Other folks have had success with Mylex controllers, and it might be worthwhile going with one of those, along with some nice high-end drives. Like I said before, though, I haven't had any direct experience with external RAID boxes, so all I can talk about is what other folks have mentioned. Ken -- Kenneth Merry ken@kdm.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message