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Re: RAID - raidframe vs hardware/controller

Well, I was talking about relatively modern southbridge chips, as found on many motherboards. BIOS settings exist for three operating modes:

        IDE (compatability?)

I just sort of assumed that setting them to RAID would do all the work and wouldn't require any additional driver support in NetBSD. Maybe I'm being naive?

My biggest fear with raidframe(4) is that it has taken me about 10 years to get almost comfortable with simple fdisk/disklabel stuff. I've seen many threads over the years about having additional considerations for the raidframe component label. But I don't think I've ever seen a single how-to cookbook.

It would be great if there was a simple step-by-step procedure written down somewhere. (If there is one, I haven't found it.)

Oh, to answer an earlier question, I'm looking only at RAID-1 (mirror) for now. I don't think I have any plans to move on to RAID-5 or -10.

On Mon, 18 Apr 2011, Brian Buhrow wrote:

        hello.  If what you mean by hardware raid is the pseudo ataraid
driver as recognized by many Promise and other ATA and SATA cards, then the
differences between hardware and software raid are minimal in terms of
performance, since ataraid(4) is merely a software raid1 driver which
honors the labeling conventions of these ATA and SATA cards.
        In terms of raid(4) versus the hardware raid management on cards like
the 3ware cards and the like, the answers to your questions, are, of
course, it depends.
        In general, I prefer using raid(4) over hardware raid controllers
because while it's possible that performance may not be as good, I've found
it to be more robust in the face of marginal disks, as well as easier to
manage while the system is still running if things do go wrong.  If the
hardware raid card you're thinking of using works well with the bioctl(8)
utility, then I think managing disks in errored states and the like will be
comparable with raidctl(8), but if not, you'll have to bring the system
down when ever you want to do maintenance work and work from the card's
bios utilities.  In my view, that obviates one of the major advantages of
raid systems.
        Just my 2 cents.
        Just thoughts from a happy raid(4) user who's used it since

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