Hi Kevin,

> Hi,
> Here's what I spent my weekend doing at home:
> I'm trying to install SL 4.1 (or 4.2 rc2?3, same results) on a 
> system that is already running Fedora Core 1.
> 
> The system has 4 60GB IDE HD's set up as a couple raid 1 arrays for 
> /usr and /var and a big raid 5 array.
> 
> When I run the installer I get errors about DMA timeouts and when it 
> eventually times out and gets to the partitioning screen, its 
> missing 1 of the drives, and even weirder, the raid1 devices that 
> were on both that drive and another drive it does see are missing as 
> well.
> 
> I though the problem might be the VIA chipset built in the 
> motherboard, so I switched to a couple ide PCI cards I had lying 
> around.  The drives are currently running off:
> 
> IDE interface: CMD Technology Inc PCI0649 (rev 02)
> Unknown mass storage controller: Promise Technology, Inc. 20267 (rev 
> 02)
> 
> although swapping controllers made no difference in symptoms.
> 
> I thought the problem might be following one of the drives, which it 
> seemed to when swapping things around, however when i tried 
> installing with the suspect drive removed, which shouldn't matter in 
> this setup, I got the same symptoms.
> 
> I tried running the installer with an ide=nodma option, and that 
> resulted in a kernel panic where it usually gets the dma errors.
> 
> Does this sound familiar to anyone?

Have you tried swapping IDE cables with new (known to work) ones?

Michael.