On 30.11.2012 15:27, Sebastian Riemer wrote: > On 30.11.2012 14:25, Oguz Yilmaz wrote: >> What is the suggested way for making Raid 0+1 (not 1+0)? >> Is it possible to make it without LVM? > > Yes, it is possible but it only makes sense if you want to mirror to > another server as most people know that the alternative DRBD is too slow > for serious storage requirements. > > Create the RAID-0 first, then take your RAID-0 device and e.g. an iSCSI > device from another storage server with the same setup and create a > RAID-1 over them. Then, you've got your stacked MD layers. > > With the flag write-mostly you can even tell the read balancing that the > remote device is slower than the local one. > I've forgotten to mention: You need a kernel >= 3.4.2 for this. Earlier kernels don't support bvec merging and therefore every IO is a slow 4 KiB IO in that RAID 0+1 setup. Btw.: LVM also supports striping but letting LVM do striping is only useful if you want to build RAID 1+0. The speed is the same as "RAID 1+0 + LVM". Only that raid10 driver doesn't scale good for >= 24 HDDs. -- 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
