bjstaff@zds-ux.UUCP (Brad Staff) (02/05/91)
Is anybody working on implementing RAID algorithms in hardware? I'd envision something like a SCSI-2 target controller, which controls N IDE/ESDI/SCSI/? disks. Or maybe something completely different? -- Brad Staff Zenith Data Systems 616-982-5791 bjstaff@zds-ux.zds.com
hburford@enint.Wichita.NCR.COM (Harry Burford) (02/11/91)
bjstaff@zds-ux.UUCP (Brad Staff) writes: |>Is anybody working on implementing RAID algorithms in hardware? I'd |>envision something like a SCSI-2 target controller, which controls N |>IDE/ESDI/SCSI/? disks. Or maybe something completely different? |>-- |>Brad Staff |>Zenith Data Systems |>616-982-5791 |>bjstaff@zds-ux.zds.com Yes. NCR demonstrated RAID hardware at Fall COMDEX '90. EMAIL your FAX number and I'll send a brochure. Or, I can put you in touch with the product manager if you have specific questions about RAID. -- Harry Burford - NCR Peripheral Products Division PHONE:316-636-8016 TELEX:417-465 FAX:316-636-8889 CALL:KA0TTY SLOWNET:3718 N. Rock Road, Wichita KS C-$erve:76226,2760 SS: 9.5 Harry.Burford@Wichita.NCR.COM
cgn@ast.COM (Chris Nieves) (02/21/91)
In article <540@zds-ux.UUCP>, bjstaff@zds-ux.UUCP (Brad Staff) writes: > Is anybody working on implementing RAID algorithms in hardware? I'd > envision something like a SCSI-2 target controller, which controls N > IDE/ESDI/SCSI/? disks. Or maybe something completely different? > -- It doesn't make a whole lot of sense to have your cpu reading data, XORing it, and writing the parity to memory, BEFORE you even start the disk request. It seems best to have a SCSI (IDE?) controller handling all of the parity generation and data correction. This way the OS would need to have very little knowledge that there is anything special out there other than a real big, fast disk. ======================================================================= Chris Nieves AST Research Irvine, CA (714) 727-8494 I'm new around here so you'll have to get my net address from the posting. Anyone thought about starting a new group: comp.periphs.raid???
tim@dell.co.uk (Tim Wright) (02/26/91)
In <3229@legs.UUCP> cgn@ast.COM (Chris Nieves) writes: >In article <540@zds-ux.UUCP>, bjstaff@zds-ux.UUCP (Brad Staff) writes: >> Is anybody working on implementing RAID algorithms in hardware? I'd >> envision something like a SCSI-2 target controller, which controls N >> IDE/ESDI/SCSI/? disks. Or maybe something completely different? >> -- >It doesn't make a whole lot of sense to have your cpu reading data, >XORing it, and writing the parity to memory, BEFORE you even start >the disk request. It seems best to have a SCSI (IDE?) controller >handling all of the parity generation and data correction. This way >the OS would need to have very little knowledge that there is anything >special out there other than a real big, fast disk. Sorry, I missed the original posting (it may be in the pipeline - the UK has been cut off from the US for a few days). Anyway, this is EXACTLY what the Dell Drive Array does. It's an EISA card which supports up to 10 IDE drives (spindle-sync'd or not), and these can be configured as N logical drives of up to five physical drives each, with or without data-guarding (XOR of the data on the redundant drive). To UNIX, it looks like an Adaptec SCSI controller. So to answer the question(s), it has been implemented in hardware and it does just look like a big, fast hard disk. Incidentally the hardware in question is an Intel i960 - you need something fairly powerful ! Tim -- Tim Wright, Dell Computer Corp., Bracknell | Domain: tim@dell.co.uk Berkshire, UK, RG12 1RW. Tel: +44-344-860456 | Uucp: ...!ukc!delluk!tim Nobody ever said I was charming before. They said, "Rimmer, you're a total git" - Red Dwarf, "Camille".
hburford@enint.Wichita.NCR.COM (Harry Burford) (02/27/91)
cgn@ast.COM (Chris Nieves) writes: |>In article <540@zds-ux.UUCP>, bjstaff@zds-ux.UUCP (Brad Staff) writes: |>> Is anybody working on implementing RAID algorithms in hardware? I'd |>It doesn't make a whole lot of sense to have your cpu reading data, |>XORing it, and writing the parity to memory, BEFORE you even start |>the disk request. It seems best to have a SCSI (IDE?) controller |>handling all of the parity generation and data correction. This way |>the OS would need to have very little knowledge that there is anything |>special out there other than a real big, fast disk. |>Chris Nieves |>AST Research |>Anyone thought about starting a new group: comp.periphs.raid??? Very interesting! The NCR Array controller handles all the data correction in hardware so the operating system thinks its talking to a real big, fast, SCSI disk. Doing RAID in software DOES make sense, however, if your major goal with ARRAY use is data reliability. Cost for special hardware is reduced, but you will pay a system performance penalty. -- Harry Burford - NCR Peripheral Products Division CALL:KA0TTY SLOWNET:3718 N. Rock Road, Wichita KS 67226-1397 CI$:76226,2760 PHONE:316-636-8016 TELEX:417-465 FAX:316-636-8086 SS:9.5 Harry.Burford@Wichita.NCR.COM 'ask me about ARRAYS'