SJS wrote:
> begin  quoting John H. Robinson, IV as of Sat, Dec 15, 2007 at 10:54:38PM 
> -0800:
>>..
> Ah, okay. Big-system stuff.

Not necessarily, these days. There are lots of hardware raid
implementations on cards that are (say) under $1K. I'm fuzzy on this but
don't even (some of) the on-board raids provide a boot-time
configuration interface.

At one time, a few years ago, you had to look harder and pay more to
find a hardware raid card that provided a software interface. We used
one when I was working at a NAS manufacturer.

The software interface might have been just a program that can be run
after boot (sometimes via remote connection -- telnet or something), or
it could have been a full-fledged api library that you could write your
own interface to, which you want if you want to control it via your NAS
management software.

> 
> I don't think I was looking at the $10k and up stuff at the time.
> Perhaps that was my mistake.
> 
>> The RAID cards that I am using now don't require any host OS driver. You
>> configure it by hitting F3 during the boot process, and managing that
>> way. However, there is no way to know if a particular disk is suffering
>> degradation unless your host system has the proper driver.
> 
> That's what blinkenlights are for. :)
> 
>> I forget the exact model number, but these are 3Ware SATA RAID cards.
> 
> ...as in a controller card that plugs into a slot?
> 
> Wouldn't a driver still be needed?

The cheaper ones just use a boot time bios extension, and expose the
raid as a scsi device. Often you  can disable the raid (on some or all)
disks controlled by that card, and they then appear as individual disks
(JBOD mode).

Regards,
..jim


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