On Fri, 17 Feb 2006, Andy Smith wrote: > On Fri, Feb 17, 2006 at 03:14:37PM +0000, Gordon Henderson wrote: > > Still scratching my head, trying to work out if raid-10 can withstand > > (any) 2 disks of failure though, although after reading md(4) a few times > > now, I'm begining to think it can't (unless you are lucky!) So maybe I'll > > just stick with Raid-6 as I know that! > > RAID-10 cannot survive the failure of *any* two disks as if two > disks in one of the mirrors died then the whole mirror would be lost > which loses you a segment of the upper stripe. *If* a second disk > dies, then with 4 didks total you have 50% chance of it being the > one you're relying on. I understand the avice in a classic RAID-1+0, but Linux native RAID-10 is somewhat different from a classic RAID-0 built in top of 2 x 2-disk RAID-1's (AIUI). I was thinking of 3 replicas in near mode, but that diminishes my overall disk capacity somewhat... (1.333 times a disk rather than 2 times a disk for R6, but if performance was significantly better I could live with it) I pickup the hardware on Monday evening, so I'll have a few days of playing. Cheers, Gordon - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
