On Thursday 09 August 2007 09:44, Les wrote: > On Thu, 2007-08-09 at 09:13 -0400, Neal Becker wrote: > > Bruno Wolff III wrote: > > > On Sun, Aug 05, 2007 at 21:42:01 -0700, > > > > > > Dave Stevens <geek@xxxxxxxxxxxx> wrote: > > >> Hello all, > > >> > > >> I'm thinking about a software RAID (0) setup for my next system > > >> revision and am curious where this occurs in (I assume) the system > > >> setup. Can anyone point me to documentation on this? > > > > > > You can do a custom disk layout during install. It isn't too hard to > > > figure out do a raid 0 install, though choosing good values for > > > chunking might take some guesswork. > > > > > > What are you going to be doing that makes you think raid 0 is > > > desirable? For modern home machines with lots of memory, this probably > > > isn't going to give you much of a speed up in typical use. It will make > > > the chances of your file system being lost because of a hardware > > > problem, about double. Raid 1 or 10 seem to be more useful for home > > > users, than raid 0. > > > > No! If the prob of failure during an interval T is pf, the prob of > > failure for an array of 2 drives during T is 1 - (1-pf)^2. > > Just for completeness it should be pointed out that this is for random > failures. If the failure mode is non-random, say a design flaw or > mechanical assembly error, the formula doesn't hold, and the error > probability is nearly the same as a single disk. Although in "real > life", the errors are likely somewhere between random and design > related, so the formula is very close to the actual figure, especially > given reasonable testing standards by the manufacturer. > > Regards, > Les H not to contradict anything said here, but Seagate estimates that the MTBF for my drive, a 7200.10 series 320 GB SATA is 700,000 hours. Half of that is still 34 years. Probably the drive will be full before then... And the backup is planned to be a separate larger drive that will mirror the system overnight. What do people recommend for that, rsync? Ideally the backup would be incremental and leave me with a drive that just needs to be configured as master (boot drive) to get me back in business. Dave -- The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness." - John Kenneth Galbraith
