[Nottingham] Big biiig problem regarding IDE-RAID

Lee nottingham at mailman.lug.org.uk
Wed Jul 16 11:14:01 2003

> The software RAID-1 mirroring is about the same, the transfers are DMA so the 
> CPU just has to set them up, not copy data between buffers.  If the hardware 

Okay, so performance wise things are cool, I've been playing with IDE
RAID 1 too with linux , on a Epox Board, all worked well, pull the power
out on the primary drive , everything is cool!!!

What I can't seem to find out is how IDE RAID handles bad sectors, okay,
I can keep going in the event of a total drive failure, but what happens
if one drive develops a clump of bad sectors, I know SCSI raid does hot
sector sparing, and relocates bad blocks with an allocation map of
somekind (yeah my knowlage is sketchy here) , but IDE??? most IDE drives
I've seen with bad sectors just wig out, and fail causing the hosts o/s
to wig out too....

so, is IDE raid just a sheep in famer's clothing?