>From my experience, it works fairly well, but there are some constraints:
- Performance is really horrible if you use IDE slaves.
Even though you say you aren't performance-sensitive, I'd
recommend against it if possible.
- Thus, to get 8 drives in a machine, you not only need
mounting, power, and cooling for 8 drives,
but also 4 available PCI slots for the Promise cards
(or maybe 3 if you can make use of onboard ATA channels).
- Cable length can be a problem. I've had good luck with the
24 inch cables, although they exceed the length specified
in the spec. Even so, it can be tough to route the cables
from the promise cards to the drives. I think it would be
completely hopeless for 8 drives with 18 inch cables.
- It may be worth getting hot-swap drive boxes, although
it will add significantly to your per-drive cost.
Be careful to get ones that support udma-66 (or at least
udma-33). This allows you to recover rather more quickly
from a drive failure, assuming you buy at least 1 extra
hot-swap box and drive. Even if you don't mind rebooting
to deal with a failure, it sure beats tearing open the machine.
Good luck,
Jan Edler
NEC Research Institute
On Mon, Jan 10, 2000 at 03:26:26PM +1100, Franc Carter wrote:
>
> I am planning to set up a large ide raid5 system. From reading the
> archives of the list it looks like the way to go is with promise
> ultra66 cards, making sure that I have good cables. I am hopeing
> to get a minimum of 8 drives into a machine. My current plan is for
> the following config:-
>
> 37gig IBM ide drives
> 2.2.14 kernel (or may be a 2.3 series)
> software raid5
> Promise Ultra66 cards
> Good quality cabling
> extra fans
>
> Any comments or suggestions ? I don't care about performance (it's
> only competing against tape drives), however I do care about dollars
> per gigabyte and reliablity.
>
> thanks
>
>
> --
> Franc Carter MEMLab, University of Sydney
> Ph: 61-2-9351-7819 Fax: 9351-6461
