On Wed, Jun 24, 2009 at 05:20, NeilBrown <neilb@xxxxxxx> wrote: > > On Wed, June 24, 2009 8:27 pm, Michael Ole Olsen wrote: > > Is it possible to reshape my /dev/md0 raid5 into raid6? > > If you are are using Linux 2.6.30, then you can > > echo raid6 > /sys/block/md0/md/level > > and it will instantly be sort-of-raid6. > It is exactly like raid6 except that the Q blocks are all one > the one drive, and drive that previously didn't exist. > If you have a spare, it will start building the Q blocks > on that drive and when it finishes you will have true raid6 > redundancy, though possibly a little less than raid6 performance, > as a real raid6 has the Q block distributed. > > When mdadm-3.1 is released, you will be able to tell the raid6 > to re-stripe with a more traditional layout. This will take quite > a while, but you can continue to use the array (though a bit more > slowly) will it progresses. > Of course you don't need to do that step if you don't want to. If a raid5 is changed to raid6, and then the raid6 is grown w/ additional disks, will that switch it to a more traditional layout, since it has to be re-striped anyway? TIA, Conway S. Smith -- 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
