Adaptec ATA Raid 1200A upgrade [END GAME]

[Alan Cox]

> Hm.  When I surface from the work this week, I'll look into that.  It sure
> looked to me--by the device names being offered--that it thought it was
> manipulating the Adaptec.

If you are using their driver yes. If you are using the Fedora driver you
should see it as two ordinary IDE controllers. In that situation the
dmraid code maps the two controllers together and understands a wide
variety of BIOS raid formats. It then uses device mapper to describe that
raid layout to the kernel.

So the sequence for the 1200A is something like

	Kernel finds two Adaptec 1200A channels (rebadged Highpoint 37x)
	dmraid reads the disk layouts and decides its an Adaptec raid
format
	dmraid tells the kernel how to interpret this
	devicemapper produces a device to this spec
	The installer/kernel/userspace use the resulting mapping

> It has embedded RAID 0 and 1 in the BIOS.  No drivers necessary to use
> it in that mode.  It's pretty old at this point; there may be errors in
> the BIOS code, but is _is_ RAID.

Its RAID in the sense the BIOS does software raid.The 1200A at least
appears to be entirely BIOS magic. The 24xx series ATA raid is real
hardware raid.

Alan