> >> > How can it increate a probility of a disk crash? Is it just because of > >using > >> > two disks? > >> > Is so, it is a nonsense. > >> > >> No. Disks come with a MTBF. If you add disks, this MTBF remains > >> (almost) constant. The MTBF of the entire raid will then decrase > >> when the number of disks increase. > > > >I wrote this already, so just for completeness: > >Higher data loss probability is caused by usage of two disks. It has nothing > >to do with RAID. > >If you use two disks without RAID0, you have the same data loss probability. > > you may have the same data loss probability per disk, but the RAID > system creates 1 logical disk out of many physical disks, therefor, > the probablity has to be worked out accros the one logical disk, > because the data is split up accross the many disks, and cannot be > recovered (from RAID 0) if any one drive fails > > in effect the probability of 1 drive maybe 1in10years, but that one > drive is only 1/n of the single logical drive, n being the number of > drives in the RAID array. > > 10 Drives set as RAID 0 > failure rate of each individual drive = 1in 10 years > 1 drive = 1/10 of logical drive > each 1/10th of the logical drive has a probabilty of failure of 1/10yr > 10 drives * 1/10 fails = 10/10 = 1/1 failure per year > > its all probability/statistics, and you can even get the chance of > disk failure within the next 10 seconds as high 50% --- either it does > or it doesnt !! > same as the dice: > >As a second example, consider this. What's the probability of rolling a "6"on a single dice? It's 1/6 , right? > either you do roll a 6 or you dont :)
Please stop this stupid theory! If you have 10 disks you have ALWAYS possibility of 10 crashes per 10 years. Regardless you use RAID0 or not. > >I don't have a bus. I can't afford it. > me niether, but i bet it'd be pretty cool going to work in your own > bus :) sure. :-) > -- > Dean Liversidge Aley Keprt
