On 27/11/17 22:30, Bill Kenworthy wrote: > Hi all, > I need to expand two bcache fronted 4xdisk btrfs raid 10's - this > requires purchasing 4 drives (and one system does not have room for two > more drives) so I am trying to see if using raid 5 is an option > > I have been trying to find if btrfs raid 5/6 is stable enough to use but > while there is mention of improvements in kernel 4.12, and fixes for the > write hole problem I cant see any reports that its "working fine now" > though there is a phoronix article saying Oracle is using it since the > fixes. > > Is anyone here successfully using btrfs raid 5/6? What is the status of > scrub and self healing? The btrfs wiki is woefully out of date :( > Or put btrfs over md-raid?
Thing is, with raid-6 over four drives, you have a 100% certainty of surviving a two-disk failure. With raid-10 you have a 33% chance of losing your array. Cheers, Wol
