On 11/10/13 09:05, Adam Goryachev wrote: > On 11/10/13 17:52, Guillaume Betous wrote: >>> RAID6, preferrably with a spare. >> I'm not comfortable with RAID 6 setup. What is the minimal number of >> hard drives for having a RAID 6 + spare ? >> > > Check wikipedia, but minimum of 4 drives for RAID6, consider 2 data > drives plus two redundant drives, allowing you to lose any two drives > (slightly better than RAID10 on 4 drives). > > In direct answer, RAID6 + hot spare is a minimum of 5 drives. > That's just the /sensible/ answer. The minimum is actually 4 drives - one data, two redundant, and one spare (though obviously there are better ways to use your drives). And with mdadm, you can tell it that three of these drives are missing. While such things might seem a bit silly, it is sometimes convenient to get your raid up and running with the setup you want even if you haven't physically got the drives in place yet - you can add them in later. -- 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
