> Unfortunately I cannot see how from raid1 of 2*1TB disks migrate to > raid1(raid10?) of 4*1TB disks
I don't think you can reshape a RAID 1 to a RAID 10. mdadm can reshape RAID 1/5/6. You can move from RAID 5 to 6 or the other way around. *Maybe* you can even reshape from 1 to RAID 5/6. I see these options: * create a second RAID 1 with the new devices, make this a pv and add it to your vg * backup all data, create a RAID 10/5/6 with all four devices * Test if you can reshape from RAID 1 to 5/6 The last option only if RAID 5/6 serves your needs. Regards, Jens
