From owner-freebsd-questions Tue Apr 28 17:16:17 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA17058 for freebsd-questions-outgoing; Tue, 28 Apr 1998 17:16:17 -0700 (PDT) (envelope-from owner-freebsd-questions@FreeBSD.ORG) Received: from mail-01.cdsnet.net (mail-01.cdsnet.net [206.107.16.35]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id RAA17028 for ; Tue, 28 Apr 1998 17:16:03 -0700 (PDT) (envelope-from mrcpu@internetcds.com) Received: (qmail 1242 invoked from network); 29 Apr 1998 00:16:00 -0000 Received: from schizo.cdsnet.net (204.118.244.32) by mail-01.cdsnet.net with SMTP; 29 Apr 1998 00:16:00 -0000 Date: Tue, 28 Apr 1998 17:16:00 -0700 (PDT) From: Jaye Mathisen X-Sender: mrcpu@schizo.cdsnet.net To: techsupport@nordicdms.com cc: Johann Visagie , freebsd-questions@FreeBSD.ORG Subject: Re: DPT RAID controller support In-Reply-To: <19980428215538430.AAA192@mail.nordicdms.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG You are mixing the 2 different types of RAID boxes out there. The external RAID controller is what you're referring to, and is certainly a viable solution and OS independent. However, for a variety of reasons, an in-cabinet solution is nice. Generally speaking, the custom/non-external RAID controllers tend to be faster, although this is not absolute. On Tue, 28 Apr 1998, Dave Walton wrote: > This brings to mind something that's been puzzling me about RAID. > Whenever someone posts a question here about what RAID controllers > are supported, the standard answer is "DPT". Now, by my > understanding, the way those are set up is something like this: > > You have a bunch of drives in a box. They are all plugged into the > RAID controller. The RAID controller is plugged into a slot in the > computer. The operating system must specifically support that RAID > controller. > > That arrangement strikes me as rather inflexible and prone to > compatibility problems. It seems better to do it this way: > > You have a bunch of drives in a box. They are all plugged into the > RAID controller, which is also mounted in the box. The RAID > controller makes the array appear as a single large SCSI device, > and is connected to any standard SCSI controller in the computer. > The operating system only needs support for whatever SCSI > controller is used. > > So... Am I right that this is a better way to do things, or is there > something important that I am missing? Does anyone have any > experience with hardware of that design that they can recommend? > > Thanks, > Dave > > > > On 28 Apr 98 at 17:39, Johann Visagie wrote: > > > Robin Harker wrote: > > > > > > I understand that FreeBSD may have support for DPT's caching RAID > > > controllers. Has anyone added functionality so that e.g. drive failures > > > and rebuilding can be handled on-line? > > > > If you're using one of DPT's own external casings (or a DEC StorageWorks > > casing, apparently [which according to one rumour I've heard is just an OEM > > manufactured DPT casing]), then disk changes will automatically be detected > > (and rebuild initiated). Rebuilding onto a "hot spare" will be initiated > > automatically regardless of how and where the disks are mounted (since it > > requires no disk swap). > > > > For "serious" housekeeping on the array you an always use the DOS version of > > DPT's StorageManager software, but that should hardly ever be necessary > > except during initial installation. > > > > PS: For the record, I have never actually used a DPT controller under > > FreeBSD. I have just acquired one one loan from a supplier with the express > > purpose of doing this - I would also be quite interested in hearing the > > experiences of anyone else with using DPT RAID controllers under FreeBSD. > > > > -- V > > > > Johann Visagie | Email: wjv@CityIP.co.za | Tel: +27 21 419-7878 > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-questions" in the body of the message > > > ---------------------------------------------------------------------- > Dave Walton > Tech Support Nordic Entertainment Worldwide > techsupport@nordicdms.com http://www.nordicdms.com > ---------------------------------------------------------------------- > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message