Hans Müller wrote: >>but raid 5 only supports a failure in *one* disk, and the rebuild of the >>raid is _very_ slow. There is big degradation if one disk is broken. >>Raid 10 can supports 2 failures in differents set of raid_1 and degradation >>with 1 disk bad is less than raid5. > tht is not correct. when one disk in each arry fail the all data are lost. > only 2 disk or more in the same arry can fail I don't know what you mean. RAID_5 - _only_ one disk can fail. RAID_10 - it's two raid 1 joined by a stripe and can fail one disk in every raid 1 set.