On Thu, 7 Nov 2002, Richard Barrington wrote: > That raises a few issues... > > So what it needs is a feature where if a shutdown is dirty or a drive fails, > it syncs? How do we know which drive is good to sync to/from? md takes one drive (usually the first one) as the one to take the data from, if the array comes out of sync > Can the md code > be reused for this? Should we even bother? AFAICS the only benefit of ataraid > over md is bootability (and compatibility with promise et al), but is that worth > the work - maybe a dual disk grub + bios drive fallback is a better idea? > > And when ataraid kicks in with inconsistent disks, which data is it really using? This depends, but probably the data is mixed from both disks.. It may even happen that two read operations on the same bytes of such an array deliver different data and that would be a very bad thing... Think of an array consisting of two disks and on one of them there is an error in the filesystem.. fsck could mean everything is good, but in the truth... > If it's not checking/syncing ever (unless done manually), how redundant is it > really - it's only taken on trust that the data is good. > > The previous reports of problems when a drive actually fails aren't very comforting > either... I think I'm going back to md raid... my opinion, md is very much better.. Able to do raid5, resyncs on errors, and the swap is not mirrored so that you can have twice as much if using both disks (or it needs only half the space) Viele Grüsse, Thorsten -- Thorsten Jungblut Universität Koblenz, Fachbereich Informatik http://www.netcorner.org/
