On 31 January 2011 10:14, Robin Hill <robin@xxxxxxxxxxxxxxx> wrote: > On Mon Jan 31, 2011 at 09:41:43AM +0000, Mathias BurÃn wrote: > >> Hi, >> >> RAID10 is (could be) setup in this way, correct? >> >> 2 devices in a RAID1 >> 2 devices in another RAID1 >> >> Then you run RAID0 on top of them. If you're lucky you can lose 2 >> devices at most (1 in each RAID1). >> > It could be, yes, or you could just use the RAID10 mode in md, which > simplifies the process and offers you a selection of different physical > layouts (some of which can offer significant performance benefits, > depending on usage). > >> If you have, say 6 HDDs, would you create 3 RAID1 volumes? Then create >> a RAID0 on top of them? >> > Yes. > >> How would one go about expanding a 4 HDD RAID10 into a 6 HDD RAID10? >> Is it "just" a matter of creating a new RAID1 array of the 2 new HDDs, >> then adding them to the RAID0, then expanding whatever is on that >> (lvm, xfs, ext4)? >> > Expansion of RAID0 (or RAID10) is not currently implemented, though > there is a workaround for RAID0. ÂThe basic steps are to convert to > RAID4 with missing parity disk, expand, then convert back to RAID0. > It's a bit more complex though as you need to prevent md from recovering > the RAID4 array first - the full command process was posted a few days > ago though, so a dig through the archives should find them. ÂProper > RAID0 expansion should be in a forthcoming (next?) mdadm release, not > sure about RAID10 expansion though. > > Otherwise, yes, those are the correct steps needed for expanding the > array and filesystem. > > Cheers, >  ÂRobin > -- >   ___ >  Â( ' }   |    Robin Hill    Â<robin@xxxxxxxxxxxxxxx> | >  / / )   Â| Little Jim says ....              Â| > Â// !!    |   Â"He fallen in de water !!"         | > Ah, good to know. Because of money and physical space vs usable storage amount, I'm probably going with RAID5 again or RAID6 for my future box. Cheers, // Mathias -- 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
