Mike Miller wrote: > The two 500 GB disks we are using cost only $250 together. It sounds like > hardware RAID controllers are very overpriced. Seriously, with those > prices, if the software RAID was impacting on performance, I might go for > a faster CPU or dual CPU system instead of buying a RAID controller. > Lets not be too hasty here, hardware raid does have some advantages still. Linux or any kernel for that matter does not deal well with the loss of a drive, if doing software raid and one of your drives fails catastrophically chances are linux will hang on hardware IO. or worse. Hardware raid controllers deal better with failed drives and do not pass the failure on to the OS to have it fail as well. Additionally, linux does not have a bootloader that understands software raid5. the only reason grub or lilo work on software raid1 is because they can read the drives as if they are not in a raid at all. You can work around this by doing a raid1 for /boot and the rest of the OS in raid5 and you must insure that the bootloader is installer on both drives that you are using for this. calling software raid "fake" is imho false. raid stands for a redundant array of inexpensive drives. doing the processing on the host cpu rather than offloading it to a daughter is immaterial. raid is raid. I'll second the 3ware suggestion, it has good monitoring tools to boot. and lastly, i highly recommend using Raid Edition drives. ATA drives do address rewriting if they detect errors, too many of those (yet not enough to actually fail the drive) will degrade the drives performance causing the raid card to kick the drive out because its too slow. causing a lot of head scratching because the diagnostics tools do not actually find anything wrong with the drive. Raid Edition drives do not do the rewriting (or as much of it) so the drive with actually fail sooner.