Date: Tue, 28 Apr 1998 14:55:38 -800 From: walton@nordicdms.com (Dave Walton) To: Johann Visagie <wjv@cityip.co.za>, freebsd-questions@FreeBSD.ORG Subject: Re: DPT RAID controller support Message-ID: <19980428215538430.AAA192@mail.nordicdms.com> In-Reply-To: <E0yUCTZ-0000jc-00@ns.cityip.co.za> References: <Z7CAxHAtNMQ1EwM9@workstationsuk.demon.co.uk> from Robin Harker at "Apr 24, 98 05:53:01 pm"
next in thread | previous in thread | raw e-mail | index | archive | help
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
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19980428215538430.AAA192>